tag:blogger.com,1999:blog-32507860701660293642024-03-24T00:10:03.350-07:00HOW ELECTRICALA Place To Share & Get Knowledge about How Electrical WorkAnonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.comBlogger83125tag:blogger.com,1999:blog-3250786070166029364.post-79086971164364686962017-02-01T03:31:00.001-08:002017-02-01T03:31:38.608-08:00ENERGY POWER SUPPLY TECHNOLOGY - THE E.HOUSE TECHNOLOGY FOR DISTRIBUTION SYSTEM,<table cellpadding="0" cellspacing="0" class="tr-caption-container" style="float: left; margin-right: 1em; text-align: left;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhj0580U7RsmTjSnPPHI4MRzlb-J-aajsc58HmMvsdm3eQDQq47GsGY8-D51599BdZmOkRn7sT_qKyrU7dLAeuhyphenhyphenj0zVhBYkeesgtM86Z67hglNPnFr-BUD3T-p4GNo9Ryev74WJwlX9GI/s1600/e+house.jpg" imageanchor="1" style="clear: left; margin-bottom: 1em; margin-left: auto; margin-right: auto;"><img alt="ehouse for power supply" border="0" height="300" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhj0580U7RsmTjSnPPHI4MRzlb-J-aajsc58HmMvsdm3eQDQq47GsGY8-D51599BdZmOkRn7sT_qKyrU7dLAeuhyphenhyphenj0zVhBYkeesgtM86Z67hglNPnFr-BUD3T-p4GNo9Ryev74WJwlX9GI/s400/e+house.jpg" title="" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Energy house for Power Supply - http://howelectrical.blogspot.com</td></tr>
</tbody></table>
Make the process of power distribution more efficient, reliable and safe with energy house power supply as new technology in Electrical power engineering and field. In many cities, infrastructures, buildings automation and industrial plants. They can be linked to industrial and building automation, and are rounded out by comprehensive support throughout the entire life-cycle. What are the benefits of Energy house for power supply solution? there are three main benefits as given below.<br />
<br />
<br />
<h3>
Benefits</h3>
There are three main benefits of energy houses for power supply solution.<br />
<br />
<ol>
<li>Cost Effective</li>
<li>Fast to install</li>
<li>Flexible</li>
</ol>
<h4>
Cost Effective</h4>
<div>
The installation of an Energy house spare you from dealing with planning, controlling and complex civil works, as well as with crafts on site and construction risks.</div>
<div>
<br /></div>
<h4>
Fast to Install</h4>
<div>
An energy house for power supply arrives at your site ready for plug commission and play. this really speeds up your lead time.</div>
<div>
<br /></div>
<h4>
Flexible</h4>
<div>
You can choose from several energy house types according to your application requirements, equip them with exactly the products you need.</div>
<h3>
Plug and Play Power Distribution</h3>
<div>
The Energy house can also be used for plant balancing of fossil and renewable energy, as reliable power supply for critical processes, for grid coupling, as well as for the grid connection of electrical energy storage systems. Energy house are optimal approach to install electrical power and control equipment for a fast and reliable power supply. An energy house is a pre-fabricated electrical building, fully equipped. Actually industries needs a reliable and efficient power supply as well as flexible solutions that can be adapted to individual requirements. Energy house for power supply are fast and very easy way to install, can be used as an interim solution. They are easy to upgrade, and used available space optimally. This makes them the most suitable option for a broad range of application.</div>
<div>
The Energy house offer more; one stop solution, consistency, safety, flexibility, cost effciency, reliability and advanced technology.</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com27tag:blogger.com,1999:blog-3250786070166029364.post-2468120812985976702017-01-30T00:45:00.000-08:002017-01-30T00:45:02.584-08:00TERTIARY WINDING OF TRANSFORMER - THREE PHASE TRANSFORMERElectrical Transformer is a static device which transform electrical energy from one electrical circuit to another electrical circuit without any direct connection. It is also used for electrical power transmission (Step-Up) and distribution the electrical power (Step-Down) and Special purposes. Commonly we know that there are two windings in transformer, The primary winding and the secondary winding. The primary winding is used for input (not fixed) and the secondary winding is used for the output whether it depend upon the situation and requirement. Now there is a question asked an engineer from our Facebook group (<a href="http://facebook.com/groups/howelectrical" target="_blank">Facebook-Group</a>) that what is Tertiary winding in the three phase transformer, the advantages and disadvantages of tertiary winding.<br />
<br />
<h3>
Working Principle Of Transformer</h3>
The working principle of transformer is totally depends upon the Faraday's Law of mutual induction.<br />
Faraday's Law of Mutual Induction is:<br />
<blockquote class="tr_bq">
"Rate of change of flux linkage with respect to time is directly proportional to the induced EMF in a conductor or a coil."</blockquote>
As you all know well about the transformer working, I will try not to discuss here again. but the main constructional parts of the transformer I share below.<br />
<h3>
Main Constructional Parts of Transformer</h3>
There are following main part of transformer in construction.<br />
<br />
<ul>
<li>Primary Winding</li>
<li>Secondary Winding</li>
<li>Magnetic Core of transformer</li>
</ul>
<div>
Now What is Primary winding? The Primary winding of transformer which produce magnetic flux when it is connected to electrical source. And What is the secondary winding? The Secondary winding of transformer is the flux, produce by primary winding, passes through the core will link with the secondary winding. This is also wound on the core of transformer and gives the desired output of the transformer. And the magnetic core of transformer is the magnetic flux produced by the primary winding that will pass through with low reluctance path linked with secondary winding and create a close magnetic circuit in the transformer.</div>
<div>
<br /></div>
<div>
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<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh0mjqT-ZJjFvkwmdnkM2Abv-CAM4bAu9ca_KvDWQT20AjycJdhMhyphenhyphent3DDYxM-vm7Wmkpmo5VsV7ygdCnVJWnRYdao-Xdt2EycZSEGFOM1vAH3jUgI5BDHpWTOfde_8vep89QJq3bWX1mU/s1600/tertiary+winding+how+electrical+blog.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="tertiary winding how electrical blog" border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh0mjqT-ZJjFvkwmdnkM2Abv-CAM4bAu9ca_KvDWQT20AjycJdhMhyphenhyphent3DDYxM-vm7Wmkpmo5VsV7ygdCnVJWnRYdao-Xdt2EycZSEGFOM1vAH3jUgI5BDHpWTOfde_8vep89QJq3bWX1mU/s640/tertiary+winding+how+electrical+blog.jpg" title="tertiary winding how electrical blog" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">tertiary winding how electrical blog</td></tr>
</tbody></table>
<h2>
<br />Tertiary Winding of Three Phase Transformer</h2>
<div>
As we already discuss, there are two windings in the transformer. There is another additional winding we used named "Tertiary Winding". This winding is used in the high rating transformer for the purposes below mentioned. Because of this third winding, the transformer with tertiary winding is also known as three winding transformer.</div>
<div>
Advantages of Tertiary Winding in three phase transformer</div>
<div>
There are following advantages of tertiary phase winding.</div>
<div>
<br /></div>
<br />
<div class="MsoNormal">
</div>
<ol>
<li>Tertiary Winding reduces the unbalancing in the primary due to unbalancing
in three phase load.</li>
<li>Tertiary Winding redistributes the flow of fault current.</li>
<li>Sometime Tertiary Winding is required to supply an auxiliary load in
different <a href="http://www.electrical4u.com/voltage-or-electric-potential-difference/" title="Voltage or Electric Potential Difference"><span style="color: windowtext; text-decoration: none; text-underline: none;">voltage</span></a> level in addition
to its main secondary load. This secondary load can be taken from tertiary
winding of three winding transformer.</li>
<li>As the tertiary
winding is connected in delta formation in 3 winding transformer, it assists in limitation of fault current
in the event of a short circuit from line to neutral.</li>
</ol>
<h4>
<span style="font-family: inherit;">Rating of Tertiary Winding.</span></h4>
<div>
</div>
<br />
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;">Rating of
tertiary winding depends upon its use. If it has to supply additional load, its
winding cross - section and design philosophy is decided as per load, and three
phase dead short circuit on its terminal with power flow from both sides of HV
& MV. In case it is to be provided for stabilizing purpose only, its cross
- section and design has to be decided from thermal and mechanical
consideration for the short duration fault currents during various fault
conditions single line to ground fault being the most onerous.</span></span><o:p></o:p></div>
<div>
<div class="MsoNormal">
<o:p></o:p></div>
</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com17University of Georgia Farm Lake, Georgia 30660, USA33.8011127 -82.98476349999998533.7978142 -82.989805999999987 33.8044112 -82.979720999999984tag:blogger.com,1999:blog-3250786070166029364.post-71174968699144891002017-01-28T03:18:00.001-08:002017-01-28T03:18:19.052-08:00WHAT IS TRANSDUCER, ITS TYPES AND WHAT IS THE APPLICATIONS OF TRANSDUCER<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgekZixisrvqgM4n9qaOBQ6GPMi18f2cPSpR7IfcUZE688fFHS1TnW2wGmf9n9zWnGCiBeJRqdtX5mzK9DARKnQZS8wUDcuPRUvinfFKUF1N6LlAmHhiRB5VBgDN_Zn_dywLmuw9gb3x8/s1600/transducer.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="transducer" border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjgekZixisrvqgM4n9qaOBQ6GPMi18f2cPSpR7IfcUZE688fFHS1TnW2wGmf9n9zWnGCiBeJRqdtX5mzK9DARKnQZS8wUDcuPRUvinfFKUF1N6LlAmHhiRB5VBgDN_Zn_dywLmuw9gb3x8/s640/transducer.jpg" title="" width="640" /></a></div>
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<span style="background: white;"><br /></span></div>
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<span style="background: white;"><br /></span></div>
<div class="MsoNormal">
<span style="background: white;"><br /></span></div>
<h3>
<span style="background: white;">What Transducer Is?</span></h3>
<div class="MsoNormal">
<span style="background: white;">A transducer is an electronic device that converts energy from one form to another. Common examples include microphones, loudspeakers, thermometers, position and pressure sensors, and</span><span class="apple-converted-space"><span style="background: white; font-size: 10.0pt; line-height: 115%; mso-bidi-font-family: Calibri; mso-bidi-theme-font: minor-latin;"> </span></span><span style="background: white;">antenna. Although not generally thought of as transducers, photocells, LEDs (light-emitting diodes), and even common light bulbs are transducers. </span>A transducer plays a very important role in any instrumentation system.</div>
<div class="MsoNormal">
<br /></div>
<h3>
Types Of Transducer:</h3>
<div class="MsoNormal">
There are many types of the transducer. Transducer can be classified into main types as below,</div>
<div class="MsoNormal">
</div>
<ul>
<li>Quantity to be measured</li>
<li>Principle of Operation</li>
</ul>
<h3>
Transducer as Quantity to be measured</h3>
<div>
<ul>
<li>Temperature transducer</li>
<li>Pressure transducer</li>
<li>Displacement transducer</li>
<li>Flow transducer</li>
</ul>
<h3>
Transducer as Principle of Operations</h3>
</div>
<div>
<ul>
<li>Chemical transducer</li>
<li>Photovoltaic transducer</li>
<li>Photoconductor transducer</li>
<li>Half effect transducer</li>
<li>Piezoelectric transducer</li>
</ul>
<h3>
Ideal Characteristics of Transducer</h3>
</div>
<div>
<ul>
<li>High dynamic range</li>
<li>High repeatability</li>
<li>Low Noise</li>
<li>Low hysteresis</li>
</ul>
</div>
<br />
<div class="MsoNormal">
<o:p></o:p></div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com7tag:blogger.com,1999:blog-3250786070166029364.post-8720936230931079462017-01-27T23:30:00.000-08:002017-01-27T23:30:24.365-08:00RHOESTAT AND POTENTIOMETER - THE DIFFERENCE BETWEEN RHEOSTAT AND POTENTIOMETER<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6C4G-LKyCrT_b2Eh1lZcjZirecVZw2ByRosmpphrY4DG7TfvhuuJqVQHVNmw7pAjRgjk6PYClhVFdbVWdk9UBniEDBukYyGClp1Azbd4DOcPJ7ZoOPpQyrPrnDJoV_wHwnoNzgM4Qwu4/s1600/apoten+vs+rheostat.jpg" style="margin-left: 1em; margin-right: 1em;"><img alt="potentiometer and rheostat" border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj6C4G-LKyCrT_b2Eh1lZcjZirecVZw2ByRosmpphrY4DG7TfvhuuJqVQHVNmw7pAjRgjk6PYClhVFdbVWdk9UBniEDBukYyGClp1Azbd4DOcPJ7ZoOPpQyrPrnDJoV_wHwnoNzgM4Qwu4/s640/apoten+vs+rheostat.jpg" title="The Difference Between potentiometer and rheostat" width="640" /></a></div>
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<div class="separator" style="clear: both; text-align: left;">
As looking wise, The potentiometer and the rheostat are looking same but there is some difference between both. I have shared some knowledgeable summarised difference below for understanding. If you found any more difference, You can share with us on below comment box.</div>
<div class="separator" style="clear: both; text-align: left;">
<br /></div>
<h2 style="clear: both; text-align: left;">
POTENTIOMETER</h2>
<div class="separator" style="clear: both; text-align: left;">
A potentiometer is a three terminal variable resistor, Usually, electricians used the potentiometer to adjust voltage, The Potentiometer can work as Rheostat but The Rheostat can not works as Potentiometer because of their properties. The Potentiometer controls the circuit's Signal level (not the power level).</div>
<div class="separator" style="clear: both; text-align: left;">
<br /></div>
<h2 style="clear: both; text-align: left;">
RHEOSTAT</h2>
<div class="separator" style="clear: both; text-align: left;">
A Rheostat is two terminal variable resistor, Usually, electricians use the rheostat to adjust current. The Rheostat can not work as Potentiometer (but vice versa). Electricians employ a Rheostat for handling the much higher voltage and current. A Rheostat is simply a variable resistor used to control the power to a load.</div>
<div class="separator" style="clear: both; text-align: left;">
<br /></div>
<div class="separator" style="clear: both; text-align: left;">
A Rheostat is used to vary the amount of current in the circuit but a potentiometer is used to vary the voltage between the second terminal and one of the outside terminal.</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com4University House, 725 NW 13th St, Gainesville, FL 32601, USA29.6582444 -82.3380832000000284.1362099000000008 -123.64667720000003 55.180278900000005 -41.029489200000029tag:blogger.com,1999:blog-3250786070166029364.post-87380046195485318692017-01-25T10:24:00.000-08:002017-01-27T23:54:48.177-08:00UNDERSTAND THE HAZARDS OF ELECTRIC SHOCK ON BODY AND RULES FOR SAFE PRACTICE TO AVOID ELECTRIC SHOCK<div class="separator" style="clear: both; text-align: center;">
</div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHJKqd3_wh0JQV4btGbSIW9lCp955BpO_FRW4eKmQEuKboyzyWzlCO5ijAaOlDaxR3uw5r1R_EFbf3pLG0Q0K9wf0ltI2A_q48rXljkIloyxSeBuMWZYeG0qkbMM0PL-C7bjsuFJT7gdc/s1600/electrical+hazards.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiHJKqd3_wh0JQV4btGbSIW9lCp955BpO_FRW4eKmQEuKboyzyWzlCO5ijAaOlDaxR3uw5r1R_EFbf3pLG0Q0K9wf0ltI2A_q48rXljkIloyxSeBuMWZYeG0qkbMM0PL-C7bjsuFJT7gdc/s640/electrical+hazards.jpg" width="640" /></a></div>
<h3>
<span style="font-family: inherit;">Performance objectives</span></h3>
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;">Understand the hazards of electric shock on human body and rules for safe practice to avoid electric shock. See how an amount of current is changed within the human body with the variation of resistance.</span></span></div>
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;"><br /></span></span></div>
<h3>
<span style="line-height: 115%;"><span style="font-family: inherit;">EQUIPMENT: </span></span></h3>
<div class="MsoNormal">
</div>
<ul>
<li>DC Ammeter</li>
<li>Multimeter with resistance Range 9-12 Battery</li>
</ul>
<br />
<h3>
<span style="line-height: 115%;"><span style="font-family: inherit;">What is Electric Shock</span></span></h3>
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;">An electric shock occurs when a person comes into contact with an electrical energy source. Electrical energy flows through a portion of the body causing a shock. </span></span><span style="font-family: inherit;">When Voltage increases current also increases. </span><span style="font-family: inherit;">In most cases voltage up to 50 Volts is safe. </span><span style="font-family: inherit;">Chart of Different Physiological effects of electricity</span></div>
<div class="MsoNormal">
<br /></div>
<h3>
<span style="line-height: 115%;"><span style="font-family: inherit;">Safety Rules</span></span></h3>
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;">The apparent reasons for accidents are</span></span></div>
<div class="MsoNormal">
</div>
<ol>
<li>Ignorance</li>
<li>Fatigue</li>
<li>Mental Pressure</li>
<li>Faulty or Improper Tools </li>
<li>Wrong procedure and carelessness</li>
<li>Rules for safe practice to avoid electric shock</li>
<li>Be sure of conditions of the equipment's and dangers present before working on pieces of equipment. </li>
<li>Never Rely on safety devices.</li>
<li>Never Remove the ground wire of three wire-input<span style="font-family: inherit;"> plugs.</span></li>
<li>Do not work on cultured bench</li>
<li>Do not work on wet floors</li>
<li>Do not work alone</li>
<li>Work with one hand behind you or in your pocket</li>
<li>Never talk to anyone<span style="font-family: inherit;"> while working</span></li>
</ol>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com5tag:blogger.com,1999:blog-3250786070166029364.post-18425664183479483572017-01-25T10:09:00.000-08:002017-01-25T10:09:47.086-08:00MCB, MCCB, ACB AND VCB DIFFERENCE AND CHARACTERISTICS - CIRCUIT BREAKERS<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiynno0KlLW4zmDkRmCyV1CYw3kxgu-sC_SOvzrcAgO2-_QEiEtaINfQvuMg9jeIZk7drHBCv70p9glxZ1zT8P1FDalAcOh2K9kUNRjHdBwl4SSzXxdJCXYa6yHRVpZF8thBIK-Jf7gKss/s1600/circuit-breakers.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Circuit Breakers of differents poles." border="0" height="346" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiynno0KlLW4zmDkRmCyV1CYw3kxgu-sC_SOvzrcAgO2-_QEiEtaINfQvuMg9jeIZk7drHBCv70p9glxZ1zT8P1FDalAcOh2K9kUNRjHdBwl4SSzXxdJCXYa6yHRVpZF8thBIK-Jf7gKss/s640/circuit-breakers.png" title="Circuit Breakers of differents poles." width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Circuit Breakers of differents poles.</td></tr>
</tbody></table>
<h3>
<b><span style="font-size: 12.0pt; line-height: 115%; mso-bidi-font-size: 11.0pt;"><span style="font-family: inherit;"><br /></span></span></b></h3>
<h3>
<b><span style="font-size: 12.0pt; line-height: 115%; mso-bidi-font-size: 11.0pt;"><span style="font-family: inherit;"><br /></span></span></b></h3>
<h3>
<b><span style="font-size: 12.0pt; line-height: 115%; mso-bidi-font-size: 11.0pt;"><span style="font-family: inherit;">MCB (Miniature circuit breaker)</span></span></b></h3>
<div class="MsoNormal">
</div>
<ul>
<li><span style="font-family: inherit;">The characteristics of miniature circuit breaker are below,</span></li>
<li><span style="font-family: inherit;">MCB rated current is not more than 100 A. means the current limit (or current rating) is maximum 100A).</span></li>
<li><span style="font-family: inherit;">Trip characteristics are normally meant not adjustable.</span></li>
<li><span style="font-family: inherit;"><span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><span style="text-indent: -0.25in;">MCB operation is thermal based or thermal-magnetic.</span></span></li>
</ul>
<br />
<h3>
<b><span style="font-size: 12.0pt; line-height: 115%; mso-bidi-font-size: 11.0pt;"><span style="font-family: inherit;">MCCB (Moulded case circuit breaker)</span></span></b></h3>
<div class="MsoNormal">
</div>
<ul>
<li><span style="font-family: inherit;">The characteristics of Moulded case circuit breaker are below,</span></li>
<li><span style="font-family: inherit;">The current rating of MCCB is from 101 A to 1000 A.</span></li>
<li><span style="font-family: inherit;"><span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><span style="font-stretch: normal; font-variant-numeric: normal; line-height: normal;">The </span><span style="text-indent: -0.25in;">Current of a trip (switch off the circuit) may be adjustable, means current rating we can adjust in MCCB.</span></span></li>
<li><span style="text-indent: -0.25in;"><span style="font-family: inherit;">MCCB operates in thermal or thermal-magnetic operation.</span></span></li>
</ul>
<br />
<h3>
<b><span style="font-size: 12.0pt; line-height: 115%; mso-bidi-font-size: 11.0pt;"><span style="font-family: inherit;">ACB (AIR Circuit Breaker)</span></span></b></h3>
<div class="MsoNormal">
</div>
<ul>
<li>The characteristics of ACB (Air Circuit Breaker) are below.</li>
<li>The current rating of ACB (Air circuit breaker) is from 1001 A to 10000 A.</li>
<li>Trip characteristics of Air Circuit Breaker (ACB) often fully adjustable including configurable trip thresholds and delays.</li>
<li>ACB (Air Circuit Breaker) often used in Main Electrical Panels (usually in medium voltage MV or high voltage electrical panels HV). ACB (Air circuit breaker) also usually used for main power distribution in a large industrial plant, where the breakers are arranged in drawn-out enclosures for ease of maintenance.</li>
</ul>
<br />
<h3>
<b><span style="font-family: inherit;">VCB (Vacuum Circuit Breaker)</span></b></h3>
<div class="MsoNormal">
</div>
<ul>
<li>Some important characteristics of Vacuum circuit breaker are below,</li>
<li>The VCB (Vacuum circuit breaker) current rating is up to 3000 Amperes.</li>
<li>The main characteristics of vacuum circuit breaker are, it interrupts the arc in a vacuum bottle.</li>
<li>These can be applied at up to 35 thousand volts.</li>
</ul>
<div>
Is there any other you know, Share with us from below comment box.</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com33tag:blogger.com,1999:blog-3250786070166029364.post-24295752317459037602017-01-23T08:01:00.003-08:002017-01-23T08:01:54.800-08:00WHAT IS DIELECTRIC - ELECTRICAL TECHNOLOGY BLOG - HOW ELECTRICAL WORKS.<div class="MsoNormal">
<span style="font-family: inherit;">A <b>dielectric</b> is an electrical insulator that can be polarized by an applied electric field. <o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">When a dielectric is placed in an electric field, electric charges do not flow through the material as they do in a conductor, but only slightly shift from their average equilibrium positions causing <b>dielectric polarization</b>.<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"> Because of dielectric polarization, positive charges are displaced toward the field and negative charges shift in the opposite direction. This creates an internal electric field which reduces the overall field within the dielectric itself.<o:p></o:p></span></div>
<div class="MsoNormal">
<br /></div>
<div class="MsoNormal">
<span style="font-family: inherit;">While the term "insulator" implies low electrical conduction, "dielectric" is typically used to describe materials with a high polarizability. The latter is expressed by a number called the dielectric constant.</span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">The term insulator is generally used to indicate electrical obstruction while the term dielectric is used to indicate the energy storing capacity of the material (by means of polarization).<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">If the space between the plates of a capacitor is filled with an Dielectric, the capacitance of the capacitor will change compared to the situation in which there is vacuum between the plates.<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">The change in the capacitance is caused by a change in the electric field between the plates. The electric field between the capacitor plates will induce dipole moments in the material between the plates. These induced dipole moments will reduce the electric field in the region between the plates. A material in which the induced dipole moment is linearly proportional to the applied electric field is called a <b><u>linear dielectric</u></b>.</span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><o:p></o:p></span></div>
<span style="line-height: 115%;"><span style="font-family: inherit;"><br /></span></span>
<span style="line-height: 115%;"><span style="font-family: inherit;">For linear dielectric:</span></span><br />
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgct4T4XvGD36NbcEkClw98WwCcx60u4gJPbKl7vUm6t99rr4CTBnjTEFOv7aTCCm7gcQeu6j1nQTTQbesRDBM3dFVwN6A4NR2DPNyZt73X2ZB1okJfCSWh2VFbtzg-k2Ln9GzojylzNrI/s1600/c1.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><span style="font-family: inherit;"><img border="0" height="102" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgct4T4XvGD36NbcEkClw98WwCcx60u4gJPbKl7vUm6t99rr4CTBnjTEFOv7aTCCm7gcQeu6j1nQTTQbesRDBM3dFVwN6A4NR2DPNyZt73X2ZB1okJfCSWh2VFbtzg-k2Ln9GzojylzNrI/s200/c1.png" width="200" /></span></a></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">Where <b>K</b> is called the dielectric constant. Since the final electric field E can never exceed the free electric field E<sub>free</sub>, the dielectric constant <b>k</b> must be larger than 1.<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">The potential difference across a capacitor is proportional to the electric field between the plates.<o:p></o:p></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjtsQmzSZgYu7LZkmOtmshoDbbphELokrez8mAzgg9K0KnJpPEK7qZOI2InjQrq0cVUhu1bxjRDiSFOwJjpSrehPhznWf5mb_pGfE3IYCPuDwn330q_m4DTuPjPHw5bmBDVSxALJn4JPkk/s1600/c2.gif" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><b><span style="font-family: inherit;"><img border="0" height="88" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjtsQmzSZgYu7LZkmOtmshoDbbphELokrez8mAzgg9K0KnJpPEK7qZOI2InjQrq0cVUhu1bxjRDiSFOwJjpSrehPhznWf5mb_pGfE3IYCPuDwn330q_m4DTuPjPHw5bmBDVSxALJn4JPkk/s320/c2.gif" width="320" /></span></b></a></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">Since the presence of a dielectric reduces the strength of the electric field, it will also reduce the potential difference between the capacitor plates (if the total charge on the plates is kept constant):<o:p></o:p></span></div>
<span style="line-height: 115%;"><span style="font-family: inherit;"> </span></span><br />
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;">The capacitance C of a system with a dielectric is inversely proportional to the potential difference between the plates, and is related to the capacitance C<sub>free</sub> of a capacitor with no dielectric in the following manner.</span></span></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfQDOBj14ei2ql39dJXSYzBu_vwcJMlcPoEtJl8ehsRpdomnXLgi85FQO-0oZowMEiEYqx5VF6QZhyphenhyphenPc7nhEzlqxBV7JO5ysHdcMIxiRXG93rI8Acwf1HcjBL3DF0L8DqcYvBnYY8oOp8/s1600/c4.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><span style="font-family: inherit;"><img border="0" height="70" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhfQDOBj14ei2ql39dJXSYzBu_vwcJMlcPoEtJl8ehsRpdomnXLgi85FQO-0oZowMEiEYqx5VF6QZhyphenhyphenPc7nhEzlqxBV7JO5ysHdcMIxiRXG93rI8Acwf1HcjBL3DF0L8DqcYvBnYY8oOp8/s320/c4.png" width="320" /></span></a></div>
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;"><br /></span></span></div>
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;"><br /></span></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">Since <b>k</b> is larger than 1, the capacitance of a
capacitor can be significantly increased by filling the space between the
capacitor plates with a dielectric with a large <b>k</b>.<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">The electric field between the two capacitor plates is the
vector sum of the fields generated by the charges on the capacitor and the
field generated by the surface charges on the surface of the dielectric.</span></div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com12tag:blogger.com,1999:blog-3250786070166029364.post-2887926798803604062017-01-23T06:39:00.001-08:002017-01-23T06:39:34.760-08:00INDUSTRIAL WIRING COURSE - ELECTRICAL WIRING - LEARN ELECTRICAL DRAWING<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgRc8Oy3uAVTTVKc8TJE8hHmsKvZBDM9vkuXaALmHnfB4jfPX0rt5133H6N3UDFGDS8F91N_mWwZkeB4tpYZyenynOPkOv1F9PwdUfggrDphsEpyViuTzZW0r1OsQD9kemOaZGy9h29QBU/s1600/1_121909_1.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="how electrical drawing" border="0" height="458" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgRc8Oy3uAVTTVKc8TJE8hHmsKvZBDM9vkuXaALmHnfB4jfPX0rt5133H6N3UDFGDS8F91N_mWwZkeB4tpYZyenynOPkOv1F9PwdUfggrDphsEpyViuTzZW0r1OsQD9kemOaZGy9h29QBU/s640/1_121909_1.jpg" title="" width="640" /></a></div>
<br />
<br />
Electrical Wiring or Industrial Wiring course files in which you can learn these following topics in the field of Electrical Engineering.<br />
<br />
<h3>
TOPICS YOU WILL LEARN</h3>
<div class="MsoNoSpacing">
</div>
<ol>
<li>Safety of Industry/industrial wiring safety/industry safety</li>
<li>Drawings and symbols of electrical wiring.</li>
<li>Wire types and preparations (include insulation materials, conductors, wire specification, coxial and multiway cables and insulation removal process.)</li>
<li>Soldering and termination (how to solder a wire connections, forming the wire, crimped joints, screw clamp terminals and termination coaxial cable.)</li>
<li>Cable forming connections and routing (general intro about connections and routing, conductor and cable runs and conductors of different circuits.)</li>
<li>Hardware (components mounting rails usually known as aluminuim rails, plastics trunking or usually known as cable channel made of plastic materisl, connector blocks and screw terminals).</li>
<li>Active components like connectors and relays, contactors and transformers etc.</li>
<li>Passive components like fuses, resistors and capacitors.</li>
<li>Switched and lamps.</li>
<li>Earthings and screenings (earthing the protective bonding circuit, screen connections and more)</li>
<li>The most important and advaced thing is PLC Wiring. (In which you will learn about</li>
<li>PLC installation, Power supply wiring, earthing and wiring of inputs and outputs.</li>
</ol>
<div>
Want to learn these all? Download these files with complete Wiring course from below link.</div>
<div>
<br /></div>
<div>
<a href="http://mohsinjahan.weebly.com/industrial-control-wiring.html" target="_blank">Download</a></div>
<br />
<div class="MsoNoSpacing">
<o:p></o:p></div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com60tag:blogger.com,1999:blog-3250786070166029364.post-66378825583155899032017-01-23T06:29:00.000-08:002017-01-23T06:29:06.926-08:00APPLIED ELECTRICAL TECHNOLOGY COURSE - ELECTRICAL BASICElectrical engineering course applied electrical technology for beginners and for professionals also to make strong your basic in the electrical field and it is also a big chance for all electrical engineers and relevant field to make basic strong in this field. So don't forget to download the complete course from the link I have shared below. Follow this blog by email from the below.<br />
<br />
<h4>
<a href="http://eemohsin.weebly.com/updates/applied-electrical-technology" target="_blank">APPLIED ELECTRICAL TECHNOLOGY COURSE</a></h4>
<div>
<br /></div>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggJKJ-svxUcw2acCNT9G6pXwR0GniCVLOlO337Qxz18evR0eF-vgCd1XMh08YhUwCOrMTAzmhh9ERKXfn5dB7XSZqY997rZgiJnY8jWKDt0oU6EnkC-GHydKqcsRMmWQ8xBZRZLZ8ulz8/s1600/download+%25281%2529.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="299" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEggJKJ-svxUcw2acCNT9G6pXwR0GniCVLOlO337Qxz18evR0eF-vgCd1XMh08YhUwCOrMTAzmhh9ERKXfn5dB7XSZqY997rZgiJnY8jWKDt0oU6EnkC-GHydKqcsRMmWQ8xBZRZLZ8ulz8/s400/download+%25281%2529.jpg" width="400" /></a></div>
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Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0tag:blogger.com,1999:blog-3250786070166029364.post-11151489734736427702017-01-23T04:47:00.000-08:002017-01-23T04:47:07.306-08:00EFFECTS OF ELECTRIC CURRENT - HOW ELECTRICAL WORKS<h3>
<span style="font-family: inherit; font-size: x-large;">C</span><span style="font-family: inherit; font-size: small;">urrent:</span></h3>
<span style="font-family: inherit;">The rate of flow of charges from a specific point is known as electric current. There are many effects of electric current and we can categorise it as below,</span><br />
<span style="font-family: inherit;"><br /></span>
<h3>
<span style="font-size: small;">Heating Effects</span></h3>
When electric charges move through a wire, they lose some of the energy to the atoms in the wire. On receiving the energy, The atoms vibrate more and more causing the wire to heat up. Some of the Electric Energy is changed to heat energy. The higher the resistance the more the heat energy.<br /><span style="font-family: inherit;"><br /></span><br />
<span style="font-family: inherit;">The amount of heat generated is governed by Joule's first law: </span><br />
<div class="MsoNormal">
<span style="font-family: inherit;"><b><br /></b></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><b>Q = I<sup>2</sup>·R·t </b><o:p></o:p></span></div>
<span style="line-height: 115%;"><span style="font-family: inherit;"><br /></span></span>
<span style="line-height: 115%;"><span style="font-family: inherit;">In industry soldering, welding, cutting, drilling and working of electric furnaces are based on heating of electric current.</span></span><br />
<span style="line-height: 115%;"><span style="font-family: inherit;"><br /></span></span>
<h3>
Chemical Effects</h3>
<div class="MsoNormal">
The passage of an electric current through a conducting liquid causes chemical reactions.</div>
<div class="MsoNormal">
<o:p></o:p></div>
<div class="MsoNormal">
The resulting effects are called chemical effects of electric current.<o:p></o:p></div>
<div class="MsoNormal">
Two major effects are:<o:p></o:p></div>
<div class="MsoNormal">
</div>
<ol>
<li>Electrolysis</li>
<li>Electroplating</li>
</ol>
<br />
<div class="MsoNormal">
<b>1-Electrolysis</b><o:p></o:p></div>
<div class="MsoNormal">
In chemistry and manufacturing, electrolysis is a method of using a direct electric current (DC) to drive a chemical reaction.<o:p></o:p></div>
<div class="MsoNormal">
Electrolysis is commercially highly important as a stage in the separation of elements from naturally occurring sources such as ores using an electrolytic cell.<o:p></o:p></div>
<div class="MsoNormal">
<br /></div>
<div class="MsoNormal">
<b>2 Electroplating</b><o:p></o:p></div>
<div class="MsoNormal">
The most common application of the chemical effect of electric current is electroplating.<o:p></o:p></div>
<div class="MsoNormal">
In this process, there exists a liquid, usually called the electrolyte, through which current passes. Two electrodes, connected to the terminals of a battery with a switch in between, are inserted in the liquid. <o:p></o:p></div>
<div class="MsoNormal">
Electroplating is done in industries to have an anti-reactive coating on the parts of machines so that they do not react with the raw material, to have an anti-corrosive coating for the machines so that they do not get corroded, and a heat-resistive coating for parts like boilers to resist the heat produced by the machinery. Gold plating is one of the most common applications of electroplating in ornament-making.<o:p></o:p></div>
<div class="MsoNormal">
<br /></div>
<h3>
Magnetic Effects</h3>
<div class="MsoNormal">
<o:p></o:p></div>
<div class="MsoNormal">
If a magnetic compass is placed near a conductor carrying current (wire), the needle is deflected. This shows that a conductor carrying current has a magnetic field around it.<o:p></o:p></div>
<div class="MsoNormal">
The magnetic field around a current carrying straight conductor is in concentric circles. It can be observed by passing a current carrying straight conductor through a cardboard and sprinkling iron filings on it. All motors, transformers, Alternators and most of the measuring electrical instruments use magnetic effect of electric current.</div>
<div class="MsoNormal">
<br /></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjM-vKwW_5RTFnuPoxaY1rUFFrvclSrY5PBGJ8jr2z2oRwoDceRiCht2O09p6aCleasPb0GDt4y0L8zt8W-MmozJzg6_9kM_tnU6yhcxVUgJLma85vzainVTsLHBPIdEYl2hVD1mXo2QOM/s1600/effects.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="Electro-Plating Effect Example" border="0" height="373" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjM-vKwW_5RTFnuPoxaY1rUFFrvclSrY5PBGJ8jr2z2oRwoDceRiCht2O09p6aCleasPb0GDt4y0L8zt8W-MmozJzg6_9kM_tnU6yhcxVUgJLma85vzainVTsLHBPIdEYl2hVD1mXo2QOM/s400/effects.png" title="Electro-Plating Effect Example" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Electro-Plating Effect Example.</td></tr>
</tbody></table>
<div class="MsoNormal">
<br /></div>
<div class="MsoNormal">
<o:p></o:p></div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com2tag:blogger.com,1999:blog-3250786070166029364.post-18277340245491383782017-01-23T04:30:00.003-08:002017-01-23T04:30:43.939-08:00TIME CONSTANT FOR R-L CIRCUIT - THEORY PLUS QUESTIONS<div class="MsoNormal">
<span style="font-family: inherit;">Consider the Resistance-Inductance circuit shown few lines below, </span><span style="font-family: inherit;">In the circuit on </span>previous<span style="font-family: inherit;"> slide, if the coil was not present, the current through the resistor (</span>may be<span style="font-family: inherit;"> a lamp) would immediately rise to its maximum value of E/R when you closed the switch. </span><span style="font-family: inherit;">With the coil in the circuit, as soon as current starts to flow, the self-induction in the coil produces an emf across the coil, which, by Lenz’s Law opposes the change in current through circuit, thus, the rise of current in the circuit is not as fast as that was in pure resistive circuit containing no inductive element (coil).</span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">The lamp thus experiences the sum of two opposing emfs, a constant one from the power supply, and an opposite, time-dependent one equal to -L di/dt from the self induction of the coil. <o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">Over time, the current increases more slowly as it settles down to final steady state value, which causes the emf from self-induction in the coil to decrease, and finally after some time the current in the circuit approaches to E/R.<o:p></o:p></span></div>
<br />
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;">To find an expression for the current in the circuit, we note that the sum of the voltages across the resistor and the inductor equal the voltage applied by the power supply, or:<o:p></o:p></span></div>
<div class="separator" style="clear: both; text-align: left;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgcNktUeXSy0eiaLrFikTMADpYKrJ9cIGiBfdWSP29cziiSReLUfs27fJj6j68rrXNgJRbtX7kNQqGGq8l3FdYvwT1tbWioMiNBlCkE6LjSNYfaGJp_Wde8ChTD92R7ZQewTPWj522_yNQ/s1600/p1.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="rl ckt" border="0" height="95" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgcNktUeXSy0eiaLrFikTMADpYKrJ9cIGiBfdWSP29cziiSReLUfs27fJj6j68rrXNgJRbtX7kNQqGGq8l3FdYvwT1tbWioMiNBlCkE6LjSNYfaGJp_Wde8ChTD92R7ZQewTPWj522_yNQ/s200/p1.png" title="" width="200" /></a></div>
<div class="separator" style="clear: both; text-align: left;">
<span style="font-family: "Calibri","sans-serif"; font-size: 11.0pt; line-height: 115%; mso-ansi-language: EN-US; mso-ascii-theme-font: minor-latin; mso-bidi-font-family: "Times New Roman"; mso-bidi-language: AR-SA; mso-bidi-theme-font: minor-bidi; mso-fareast-font-family: Calibri; mso-fareast-language: EN-US; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin;">The solution to this differential equation is:</span></div>
<div class="separator" style="clear: both; text-align: left;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhc_s5K3ZOi2es6lVJOV0exyIQ2Ec88wiLq2E51yMPNE3xdvWdgU8cbS9L32hwXU4Ar2HJhLopPNlzxra5yagrOpwtD0SFAOzlEoWTJukffaFrI-InULRukTacb9MhnN7zzC5m8nXXRq_Y/s1600/P2.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="79" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhc_s5K3ZOi2es6lVJOV0exyIQ2Ec88wiLq2E51yMPNE3xdvWdgU8cbS9L32hwXU4Ar2HJhLopPNlzxra5yagrOpwtD0SFAOzlEoWTJukffaFrI-InULRukTacb9MhnN7zzC5m8nXXRq_Y/s200/P2.png" width="200" /></a></div>
<div class="MsoNormal">
which we can also write as:<o:p></o:p></div>
<div class="separator" style="clear: both; text-align: left;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhm1nFVqGDpmPpSfkWxFJYVgIBx69mt06tE7Xnqaaz8eufhVcwAgCCVRToSAlNA5atO9o3iOTozUrGm3uaQiMNCL66YVC05ehs82xTaceWiVIQp9YR7mz4JJZNzti7gp72_xW7lgPF0mY8/s1600/P3.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="80" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhm1nFVqGDpmPpSfkWxFJYVgIBx69mt06tE7Xnqaaz8eufhVcwAgCCVRToSAlNA5atO9o3iOTozUrGm3uaQiMNCL66YVC05ehs82xTaceWiVIQp9YR7mz4JJZNzti7gp72_xW7lgPF0mY8/s200/P3.png" width="200" /></a></div>
<div class="MsoNormal">
where τ<sub>L</sub>, the inductive time constant, equals L/R.<o:p></o:p></div>
<h2>
L/R Time Constant</h2>
<div class="MsoNormal">
<o:p></o:p></div>
<div class="MsoNormal">
The time constant of a series RL circuit equal to the value of inductance divided by the resistance: <o:p></o:p></div>
<h4>
T = L / R</h4>
<div class="MsoNormal">
<o:p></o:p></div>
<div class="MsoNormal">
where,<o:p></o:p></div>
<div class="MsoNormal">
T = time constant in seconds <br />L = inductance in henries <br />R = resistance in ohms <o:p></o:p></div>
<div class="MsoNormal">
<br /></div>
<div class="MsoNormal">
<span style="font-size: large;">The LR TIME CONSTANT</span> is a valuable tool for determining the time required for current in an inductor to reach a specific value. As shown in the illustration on next slide, one L/R time constant is the time required for the current in an inductor to increase to 63.2 percent of the maximum current. <span style="font-family: Calibri, sans-serif; font-size: 11pt;">Inductor current build-up is considered complete at the end of </span>5 time<span style="font-family: Calibri, sans-serif; font-size: 11pt;"> constants. </span></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiiH8pg9NpoPX5CajawAeEcT_Iql90gPS1A4jqiqqcu0AqoDsGQfgIl6xmyd7Zi-nxk1kD4GFph-DOlFNcjqeJNwuoFmIChMI4-byR5QZStnhbqr4U4OI_le5wW71oMf2JFMICrkMnb0GU/s1600/P5.gif" imageanchor="1" style="clear: left; float: left; margin-bottom: 1em; margin-right: 1em;"><img alt="rl circiut" border="0" height="275" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiiH8pg9NpoPX5CajawAeEcT_Iql90gPS1A4jqiqqcu0AqoDsGQfgIl6xmyd7Zi-nxk1kD4GFph-DOlFNcjqeJNwuoFmIChMI4-byR5QZStnhbqr4U4OI_le5wW71oMf2JFMICrkMnb0GU/s400/P5.gif" title="" width="400" /></a></div>
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<br /></div>
<h3>
RL Decay Curve</h3>
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<o:p></o:p></div>
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Inductor current does not drop off at a steady rate. Rather, the rate of current decay is discharge is rapid at first, but slows considerably as the charge approaches zero. <o:p></o:p></div>
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During each time constant, the current decays 63.2% of the remaining distance to the minimum current level.<o:p></o:p></div>
<div class="MsoNormal">
</div>
<div class="MsoNormal">
Inductor current decay is considered complete at the end of 5 time constants.<o:p></o:p></div>
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjnj1L47LNOhbZuflyoss4j48nXHdYphwl8vJgcU3XULoNCTY8ov_uu7jHiIfpptGyL-_zSg536jhThtJ4clJtGIkLPgCQlQb0rqF4OA952M3888ZzcMlRv7nvR14-zh31Of4EtWn9I6Xw/s1600/P6.gif" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img border="0" height="272" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjnj1L47LNOhbZuflyoss4j48nXHdYphwl8vJgcU3XULoNCTY8ov_uu7jHiIfpptGyL-_zSg536jhThtJ4clJtGIkLPgCQlQb0rqF4OA952M3888ZzcMlRv7nvR14-zh31Of4EtWn9I6Xw/s400/P6.gif" width="400" /></a></div>
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<span style="font-family: inherit;">Questions for practice.</span></div>
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<span style="font-family: inherit;"><br /></span></div>
<h4>
<span style="font-family: inherit;">Q.1- What is the time constant of a series RL circuit where R = 1 kW and L = 1 mH? </span></h4>
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<span style="font-family: inherit;"><o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: inherit;"><br /></span></div>
<h4>
<span style="line-height: 115%;"><span style="font-family: inherit;">Q.2- The steady-state maximum current through a 1.2 H inductor is 12 A. When this inductor is switched from the power source to a 1 W resistor, what is the current at the end of 3 time constants?</span></span></h4>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0tag:blogger.com,1999:blog-3250786070166029364.post-91778748426931290782017-01-23T03:59:00.000-08:002017-01-23T04:12:03.083-08:00NUCLEAR POWER PROCESS - NUCLEAR FISSION PROCESS - RADIOACTIVE DECAY<div class="MsoNormal">
<span style="font-family: inherit;"><span style="line-height: 115%;"><b><span style="font-size: x-large;">R</span>adioactive decay</b></span><span style="line-height: 115%;">, also known as nuclear decay or radioactivity, is the process by which a nucleus of an unstable atom loses energy in the form of radiations. </span></span><span style="font-family: inherit;">A material that spontaneously emits this kind of radiation - which includes the emission of energetic alpha particles, beta particles, and gamma rays - is considered radioactive. </span><span style="font-family: inherit;">When unstable nuclei decompose in nature, the process is referred to as natural radioactivity or spontaneous radioactivity. </span><span style="font-family: inherit;">When the unstable nuclei are prepared in the laboratory, the decomposition is called induced radioactivity.</span></div>
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<span style="font-family: inherit;"><span style="line-height: 115%;"><br /></span></span>
<h4>
<span style="font-family: inherit;"><span style="line-height: 115%;">Fission</span><span style="line-height: 115%;"> is a splitting of something into two parts.</span></span></h4>
</div>
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<span style="line-height: 115%;"><span style="font-family: inherit;">In nuclear physics and nuclear chemistry, nuclear fission is either a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into smaller parts (lighter nuclei). </span></span></div>
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<span style="line-height: 115%;"><span style="font-family: inherit;">The fission process often produces free neutrons and photons (in the form of gamma rays), and releasing a very large amount of energy. </span></span><span style="font-family: inherit;">When a nucleus fissions, it splits into several smaller fragments. These fragments, or fission products, are about equal to half the original mass. Two or three neutrons are also emitted. </span><span style="font-family: inherit;">The sum of the masses of these fragments is less than the original mass. This 'missing' mass has been converted into energy according to Einstein's equation:</span></div>
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<h3>
<span style="font-family: inherit;"><span lang="EN-GB" style="line-height: 115%;"> E = mc<sup>2</sup></span></span></h3>
</div>
<span style="font-family: inherit;">Fission can occur when a nucleus of a heavy atom captures a neutron, or it can happen spontaneously.</span><br />
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<span style="line-height: 115%;"><span style="font-family: inherit;"><br /></span></span></div>
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<h2>
<span style="font-family: inherit;"><span lang="EN-GB" style="line-height: 115%;">The Fission Process</span></span></h2>
</div>
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<span style="font-family: inherit;"><span lang="EN-GB" style="line-height: 115%;">A neutron travels at high speed towards a uranium-235 nucleus. </span></span><span style="font-family: inherit;">A neutron travels towards a uranium-235 nucleus. </span><span style="font-family: inherit;">The neutron strikes the nucleus which then captures the neutron. </span><span style="font-family: inherit;"><span lang="EN-GB" style="line-height: 115%;">The nucleus changes from being uranium-235 to uranium-236 as it has captured a neutron. </span></span><span style="font-family: inherit;">The uranium-236 nucleus formed is very unstable. </span><span style="font-family: inherit;">It transforms into an elongated shape for a short time.</span></div>
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<span style="font-family: inherit;"><span lang="EN-GB" style="line-height: 115%;">The uranium-236 nucleus formed is very unstable. </span></span><span style="font-family: inherit;">It transforms into an elongated shape for a short time. </span><span style="font-family: inherit;">The uranium-236 nucleus formed is very unstable. </span><span style="font-family: inherit;">It transforms into an elongated shape for a short time. </span><span style="font-family: inherit;">It then splits into 2 fission fragments and releases neutrons. </span><span style="font-family: inherit;">It then splits into 2 fission fragments and releases neutrons.</span></div>
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<span style="font-family: inherit;"><span style="line-height: 115%;"><br /></span></span>
<h2>
<span style="font-family: inherit;"><span style="line-height: 115%;">Nuclear Chain Reactions:</span></span></h2>
</div>
<div class="MsoNormal">
<span style="line-height: 115%;"><span style="font-family: inherit;">A chain reaction refers to a process in which neutrons released in fission produce an additional fission in at least one further nucleus. </span></span><span style="font-family: inherit;">This </span>nucleus, in turn,<span style="font-family: inherit;"> produces neutrons, and the process repeats. The process may be controlled (nuclear power) or uncontrolled (nuclear weapons). </span><br />
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8dqqXqbnQM1RKvJjHc8isY1QVDWjYDP3omY-sb-9lvZAqyHC7PEdDjVKBDHeloOnf-fQmG7lo1QvfQt8ZJ8ogfNOjdBLLHa9Zz9dxzaWyaCkYNBva8A3mIaUZS6uib1tySeTkjJgWmMA/s1600/PIC2.jpg" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="nuclear fission process" border="0" height="320" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8dqqXqbnQM1RKvJjHc8isY1QVDWjYDP3omY-sb-9lvZAqyHC7PEdDjVKBDHeloOnf-fQmG7lo1QvfQt8ZJ8ogfNOjdBLLHa9Zz9dxzaWyaCkYNBva8A3mIaUZS6uib1tySeTkjJgWmMA/s400/PIC2.jpg" title="" width="400" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Image from University of Florida</td></tr>
</tbody></table>
<h4>
<b><span lang="PT-BR" style="line-height: 115%;"><span style="font-family: inherit;">U<sup>235</sup> + n → fission + 2 or 3 n + 200 MeV</span></span></b></h4>
<div class="MsoNormal">
<span style="font-family: inherit;"><span style="line-height: 115%;">If each neutron releases two more neutrons, then the number of fissions doubles each generation. </span>In that case, in 10 generations there are 1,024 fissions and in 80 generations about 6 x 10<sup> 23</sup> fissions.</span></div>
<h4>
<b><span lang="FR" style="line-height: 115%;"><span style="font-family: inherit;">1 MeV (mega electron volts) = 1.609 x 10 <sup>-13</sup> joules</span></span></b></h4>
<br />
<div class="MsoNormal">
<span style="font-family: inherit;">Uranium-235 combines with a neutron to form an unstable Uranium-236, which quickly splits into barium-144 and krypton-89 plus three neutrons in the process of nuclear fission.</span></div>
<table align="center" cellpadding="0" cellspacing="0" class="tr-caption-container" style="margin-left: auto; margin-right: auto; text-align: center;"><tbody>
<tr><td style="text-align: center;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhLVFHoHImjIlUQkymjUx2XAIrAQm3UD3ps21qO0SflrFsUyOZDaTXRoFUqOOGOztyYIFMWUCGtX_4xZOsjwNCY2K01JU4rUMDu8mJtBSrmLJz2_GuDho9cBWulXC5N7i_daXQZnMzBcyU/s1600/PIC3.png" imageanchor="1" style="margin-left: auto; margin-right: auto;"><img alt="fission" border="0" height="380" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhLVFHoHImjIlUQkymjUx2XAIrAQm3UD3ps21qO0SflrFsUyOZDaTXRoFUqOOGOztyYIFMWUCGtX_4xZOsjwNCY2K01JU4rUMDu8mJtBSrmLJz2_GuDho9cBWulXC5N7i_daXQZnMzBcyU/s640/PIC3.png" title="" width="640" /></a></td></tr>
<tr><td class="tr-caption" style="text-align: center;">Image from University of Dehli<br /></td></tr>
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<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiQJJDgo0xkjLBBqAfT4vmCvKRD8CrbRNF2skHLQlW_q8s5vabdgQNgZsXUOJId3omd2xsjtZyZFfO6R7R1MJ4PsZg59uDuMWUnaOYt0Safn-sl876jg537NKZcJqz2PxvZ0xNUkx2PdcI/s1600/PIC4.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="fission process" border="0" height="544" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiQJJDgo0xkjLBBqAfT4vmCvKRD8CrbRNF2skHLQlW_q8s5vabdgQNgZsXUOJId3omd2xsjtZyZFfO6R7R1MJ4PsZg59uDuMWUnaOYt0Safn-sl876jg537NKZcJqz2PxvZ0xNUkx2PdcI/s640/PIC4.jpg" title="" width="640" /></a></div>
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<h2>
<span style="font-family: inherit;"><span lang="EN-GB" style="line-height: 115%;">Energy from Fission</span></span></h2>
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<span lang="EN-GB" style="line-height: 115%;"><span style="font-family: inherit;">Both the fission fragments and neutrons travel at high speed. </span></span>The kinetic energy of the products of fission are far greater than that of the bombarding neutron and target atom.</div>
<h4>
<b><i><span lang="EN-GB" style="line-height: 115%;">E<sub>K</sub> before fission << E<sub>K</sub> after fission</span></i></b></h4>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">Energy is being released as a result of the fission reaction. </span>The energy released can be calculated using the equation:</div>
<h4>
<span lang="EN-GB" style="line-height: 115%;"> E = mc<sup>2</sup></span></h4>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">Where:</span><span style="line-height: 115%;"><o:p></o:p></span></div>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">E = energy released (J)</span><span style="line-height: 115%;"><o:p></o:p></span></div>
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<span lang="EN-GB" style="line-height: 115%;">m = mass difference (kg)</span><span style="line-height: 115%;"><o:p></o:p></span></div>
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<span lang="EN-GB" style="line-height: 115%;">c = speed of light in a vacuum (3 x 10<sup>8</sup> ms<sup>-1</sup>)</span><span style="line-height: 115%;"><o:p></o:p></span></div>
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<span lang="EN-GB" style="line-height: 115%;"><br /></span></div>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">The energy released from this fission reaction does not seem a lot. </span>This is because it is produced from the fission of a single nucleus. Large amounts of energy are released when a large number of nuclei undergo fission reactions. Each uranium-235 atom has a mass of 3.9014 x 10<sup>-25</sup> kg.</div>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">The total number of atoms in 1 kg of uranium-235 can be found as follows: </span>No. of atoms in 1 kg of uranium-235 = 1/3.9014 x 10<sup>-25. </sup>No. of atoms in 1 kg of uranium-235 = 2.56 x 10<sup>24</sup> atoms</div>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">If one uranium-235 atom undergoes a fission reaction and releases 2.385 x 10<sup>-11</sup> J of energy, then the amount of energy released by 1 kg of uranium-235 can be calculated as follows:</span><span style="line-height: 115%;"><o:p></o:p></span></div>
<div class="MsoNormal">
<i><span lang="EN-GB" style="line-height: 115%;">total energy = energy per fission x number of atoms</span></i><span style="line-height: 115%;"><o:p></o:p></span></div>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">total energy = 2.385 x 10<sup>-11</sup> x 2.56 x 10<sup>24</sup></span><span style="line-height: 115%;"><o:p></o:p></span></div>
<div class="MsoNormal">
<span lang="EN-GB" style="line-height: 115%;">total energy = 6.1056 x 10<sup>13</sup> J</span><span style="line-height: 115%;"><o:p></o:p></span></div>
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<b><u><span style="line-height: 115%;"><br /></span></u></b></div>
<h2>
<span style="line-height: 115%;"><span style="font-size: x-large;">C</span>ritical mass</span><span style="line-height: 115%;">: <o:p></o:p></span></h2>
<div class="MsoNormal">
<span style="line-height: 115%;">Although two to three neutrons are produced for every fission, not all of these neutrons are available for continuing the fission reaction. If the conditions are such that the neutrons are lost at a faster rate than they are formed by fission, the chain reaction will not be self-sustaining.<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="line-height: 115%;">At the point where the chain reaction can become self-sustaining, this is referred to as critical mass. <o:p></o:p></span></div>
<div class="MsoNormal">
<span style="line-height: 115%;">In an atomic bomb, a mass of fissile material greater than the critical mass must be assembled instantaneously and held together for about a millionth of a second to permit the chain reaction to propagate before the bomb explodes. </span>To maintain a sustained controlled nuclear reaction, for every 2 or 3 neutrons released, only one must be allowed to strike another uranium nucleus.</div>
<div class="MsoNormal">
<span style="line-height: 115%;">If this ratio is less than one then the reaction will die out; if it is greater than one it will grow uncontrolled (an atomic explosion). </span>A neutron absorbing element must be present to control the amount of free neutrons in the reaction space.</div>
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<span style="line-height: 115%;">Most reactors are controlled by means of control rods that are made of a strongly neutron-absorbent material such as boron or cadmium.<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="line-height: 115%;"><br /></span></div>
<div class="MsoNormal">
<span style="line-height: 115%;">The <b>nuclear force</b> (or <b>nucleon–nucleon interaction</b> or <b>residual strong force</b>) is the force between two or more nucleons. It is responsible for binding of protons and neutrons into atomic nuclei. The energy released by such binding causes the masses of nuclei to be less than the total mass of the protons and neutrons which form them; this is the energy used in nuclear power and nuclear weapons. The force is powerfully attractive between nucleons at distances of about 1 femtometer (fm) between their centers, but rapidly decreases to insignificance at distances beyond about 2.5 fm. At very short distances less than 0.7 fm, it becomes repulsive, and is responsible for the physical size of nuclei, since the nucleons can come no closer than the force allows. So, if you feel anything important missed from here so you can comment below and mention How Electrical.</span></div>
</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0COMSAT University, Islamabad, Pakistan33.7293882 73.09314610000001333.5179472 72.770422600000018 33.9408292 73.415869600000008tag:blogger.com,1999:blog-3250786070166029364.post-70453609476550868932017-01-22T11:31:00.002-08:002017-01-22T12:12:42.679-08:00ELECTRICAL CIRCUIT COMPLETE TRAINING COURSE<span style="font-family: inherit;">We launched "Electrical Engineering Training Course" in sub-branch of electrical engineering to learn about <b>How electrical works</b> and what is the latest technology in Electrical field and what's going on? So, the course name is "Electrical Circuit" in this course you can learn about these following topics,</span><br />
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<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-iRzhdGK1OnSmoxSGUdPDxWbLBFrPVbMCwpS1V5N2uN3_QF8JBfxFhnuqEqsqA-f8HYI8_lCAWYYPBCjfzqq5AXekm6SgkuZ1-Xfo-1_5AVzzpLXfQ_bRlMIQ0eXXeJAHEysMnz47Sdc/s1600/images+%252819%2529.jpg" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img alt="technical courses free" border="0" height="224" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh-iRzhdGK1OnSmoxSGUdPDxWbLBFrPVbMCwpS1V5N2uN3_QF8JBfxFhnuqEqsqA-f8HYI8_lCAWYYPBCjfzqq5AXekm6SgkuZ1-Xfo-1_5AVzzpLXfQ_bRlMIQ0eXXeJAHEysMnz47Sdc/s400/images+%252819%2529.jpg" title="" width="400" /></a></div>
<span style="font-family: inherit;"><br /></span>
<br />
<ul>
<li><span style="font-family: inherit;">DC Circuits</span></li>
<li><span style="font-family: inherit;">Ohm's law</span></li>
<li><span style="font-family: inherit;">Kirchhoff's laws</span></li>
<li><span style="font-family: inherit;">voltage</span></li>
<li><span style="font-family: inherit;">current</span></li>
<li><span style="font-family: inherit;">voltage and current division</span></li>
<li><span style="font-family: inherit;">nodal and mesh analysis</span></li>
<li><span style="font-family: inherit;">network theorems</span></li>
<li><span style="font-family: inherit;">AC circuits analysis</span></li>
<li><span style="font-family: inherit;">phasor concepts</span></li>
<li><span style="font-family: inherit;">AC power</span></li>
<li><span style="font-family: inherit;">Three phase AC circuits</span></li>
<li><span style="font-family: inherit;">Introduction to electronics and digital logics</span></li>
</ul>
<br />
<div>
<span style="font-family: inherit;">You should have a background of the following topics:</span></div>
<div>
<ol>
<li><span style="font-family: inherit;">Coulomb's Laws</span></li>
<li><span style="font-family: inherit;">Magnetic and electric fields.</span></li>
<li><span style="font-family: inherit;">Dielectrics and capacitice.</span></li>
<li><span style="font-family: inherit;">Resistance and electric curcuits.</span></li>
<li><span style="font-family: inherit;">Electromagnetic induction.</span></li>
</ol>
<div>
<h3>
<span style="font-family: inherit;">Upon successful completion of this course, the student should be able to:</span></h3>
<div>
<span style="font-family: inherit;">1. Understand the definitions of basic electrical quantities, Ohm's and Kirchhoff’s laws, and differences between practical/ideal sources.</span></div>
<div>
<span style="font-family: inherit;">2. Analyse simple series and parallel resitive circuits and simplify series/parallel connected sources and resistors.</span></div>
<div>
<span style="font-family: inherit;">3. Implement general nodal and mesh analysis and other circuit analysis techniques and select between them to achieve optimal solution.</span></div>
<div>
<span style="font-family: inherit;">4. Understand the concept of the sinusoidal forcing function and anlayse R/L/C cirucits in the frequency domain and convert the solution to the time domain.</span></div>
<div>
<span style="font-family: inherit;">5. Three phase circuits, and power calculations.</span></div>
<div>
<span style="font-family: inherit;">6. Basic electronics, and Basic Operational Amplifier circuits and systems.</span></div>
<div>
<span style="font-family: inherit;">7. Basic Digital Logic gates and Systems. Introduction to Programmable Logic Controllers (PLC)</span></div>
</div>
</div>
<div>
<span style="font-family: inherit;"><br /></span></div>
<div>
<h2>
Course Topics:</h2>
<div>
<br /></div>
<div>
Units, charge, current, voltage, and power. Independent and Dependent voltage and current sources. Ohm's law.</div>
<div>
Branches, nodes, paths, loops, and meshes. Kirchhoff's current and voltage laws. Single node and loop circuits. Reduction of series or parallel circuits. Voltage and current division.</div>
<div>
Nodal voltage analysis and super-node. Mesh current analysis and super-mesh. Nodal vs. mesh analysis. Computer aided circuit analysis.</div>
<div>
Linearity and superposition. Thevinin's and Nortons theorems, Source transformations, max. Power transfer, delta () – wye (Y) conversion. Selecting an optimal technique for solution.</div>
<div>
The capacitor and inductor. Inductance and capacitance combinations.</div>
<div>
Characteristics of sinusoids. The phasor and relationships of single phase for R, L, and C elements. Impedance and admittance. Circuit analysis techniques. R, L& C series and parallel resonance circuits. Phasor diagrams. Three-phase circuits, Wye (Y) and Delta () balanced sources and loads.</div>
<div>
Power calculations for single and three phase circuits; power factor, power triangle. Power factor (improvement) correction.</div>
<div>
Basic electronics including; p-n junction, diodes, transistors, simple transistor amplifier circuits, basic Operational Amplifiers (OPAMP), and applications.</div>
<div>
Basic digital logic systems including: Numbering systems, Boolean’s algebra, Basic logic gates, basic digital circuits and systems. Introduction to Programmable Logic Controllers (PLC).</div>
</div>
<div>
<br /></div>
<h2 style="text-align: center;">
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Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0Jordan Rd, Las Cruces, NM 88001, USA32.2838311 -106.7495248000000232.2821531 -106.75204630000002 32.2855091 -106.74700330000002tag:blogger.com,1999:blog-3250786070166029364.post-71855129600122930862017-01-22T09:36:00.000-08:002017-01-22T09:45:59.626-08:00WHY WE USE AC MOTOR INSTEAD OF DC MOTOR - APPLICATIONS OF AC MOTORS AND APPLICATIONS OF DC MOTORS<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjdzjjStTL54C3UEJhMjghx3aFBnNNeBoARDlOs2p0BA4hE7lUPH5F-9evCOAc0kAsvAPDLSSfXPPLPE2Y9OyU-NZq9rbotJ9ocTXBxRR-bPzAPbjeEwmFhKv-BY2ss64_JRwi38dY1Zls/s1600/ddd.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="Electric Motor" border="0" height="453" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjdzjjStTL54C3UEJhMjghx3aFBnNNeBoARDlOs2p0BA4hE7lUPH5F-9evCOAc0kAsvAPDLSSfXPPLPE2Y9OyU-NZq9rbotJ9ocTXBxRR-bPzAPbjeEwmFhKv-BY2ss64_JRwi38dY1Zls/s640/ddd.jpg" title="" width="640" /></a></div>
<span style="font-family: inherit;"><br /></span> <span style="font-family: inherit;"><br /></span> <span style="font-family: inherit;">For electrical technology, Motor is known as the main unit of electrical technology. because of motor use in all industries with all machines and usually all the places normally. the Electrical motor is the main sub-sub-branch of electrical engineering because it is not easy to learn all concepts about electrical motor technology. There are many types and kinds of electrical motors like,</span><br />
<br />
<ol>
<li>AC motors</li>
<li>DC motors</li>
</ol>
<br />
<span style="font-family: inherit;">and there are also differents kinds in AC motors and DC motors as synchronous motors, induction motors, explosion proof, low voltage and motor with permanent magnet etc.</span><br />
<span style="font-family: inherit;"><br /></span>
<br />
<h3>
<span style="font-family: inherit;">Where We Use AC Motors:</span></h3>
<span style="font-family: inherit;">The alternating current electric motor (AC motors) are ideal for most applications linear, for fans, pumps, compressors, mills, machine tools, boilers, robots, generators and in many other products categories.</span><br />
<span style="font-family: inherit;">As regarding the choice of the type of electric motor for a given application, this is influenced by different factors, starting from the costs of purchase and operation, the yield, the efficiency, the periodic maintenance.</span><br />
<span style="font-family: inherit;"><br /></span>
<br />
<h3>
<span style="font-family: inherit;">Where We Use DC Motors:</span></h3>
<span style="font-family: inherit;"><br /></span>
<br />
<div class="qtext_para" style="margin-bottom: 1em; padding: 0px;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1zpLtcjov5mzdzbFoXZ9RtJFlaPO6J7vSCFDrnJPs045NUrg1P0EYRi8YRVZwL7GO3oPdnWnS9888BOtEpmcr9CXA4o0D52dkGLqF3q__VKVJbANyroaNjBZhLZ-wgfk5GLVHpfldleg/s1600/dc.png" imageanchor="1" style="clear: right; float: right; margin-bottom: 1em; margin-left: 1em;"><img alt="dc motor" border="0" height="295" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg1zpLtcjov5mzdzbFoXZ9RtJFlaPO6J7vSCFDrnJPs045NUrg1P0EYRi8YRVZwL7GO3oPdnWnS9888BOtEpmcr9CXA4o0D52dkGLqF3q__VKVJbANyroaNjBZhLZ-wgfk5GLVHpfldleg/s400/dc.png" title="" width="400" /></a><span style="font-family: inherit;">A DC motor is an electric motor that runs on direct current power. In any electric motor, the operation is dependent upon simple electromagnetism. A current carrying conductor generates a magnetic field, when this is then placed in an external magnetic field, it will encounter a force proportional to the current in the conductor and to the strength of the external magnetic field Resources and Information. is a device which converts electrical energy to mechanical energy. It works on the fact that a current carrying conductor placed in a magnetic field experiences a force which causes it to rotate with respect to its original position. </span><span style="font-family: inherit;">Practical DC Motor consists of field windings to provide the magnetic flux and armature which acts as the conductor.</span><br />
<span style="font-family: inherit;"><br /></span>
<h2 style="color: #333333; margin-bottom: 1em; padding: 0px;">
<span style="font-family: inherit;">Applications of DC Motors</span></h2>
<h3 style="color: #333333; margin-bottom: 1em; padding: 0px;">
<span style="font-family: inherit;">Series Motors</span></h3>
<div class="qtext_para" style="color: #333333; margin-bottom: 1em; padding: 0px;">
<span style="font-family: inherit;">The series DC motors are used where high starting torque is required, and variations in speed are possible. For example – the series motors are used in Traction system, Cranes, air compressors.</span></div>
<h3 style="color: #333333; margin-bottom: 1em; padding: 0px;">
<span style="font-family: inherit;">Shunt Motors</span></h3>
<div class="qtext_para" style="color: #333333; margin-bottom: 1em; padding: 0px;">
<span style="font-family: inherit;">The shunt motors are used where constant speed is required and starting conditions are not severe. The various applications of DC shunt motor are in Lathe Machines, Centrifugal Pumps, Fans, Blowers, Conveyors, Lifts, Weaving Machine, Spinning machines, etc.</span></div>
<h3 style="color: #333333; margin-bottom: 1em; padding: 0px;">
<span style="font-family: inherit;">Compound Motors</span></h3>
<span style="font-family: inherit;"></span><br />
<div class="qtext_para" style="color: #333333; margin-bottom: 1em; padding: 0px;">
<span style="font-family: inherit;">The compound motors are used where higher starting torque and fairly constant speed is required. The examples of usage of compound motors are in Presses, Shears, Conveyors, Elevators, Rolling Mills, Heavy Planners, etc.</span></div>
</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com2University Station, 5400 Ponce de Leon, Coral Gables, FL 33146, USA25.714868 -80.2770269999999750.192833499999999 -121.58562099999997 51.2369025 -38.968432999999976tag:blogger.com,1999:blog-3250786070166029364.post-30325462931993828572017-01-21T10:46:00.002-08:002017-01-21T10:46:40.170-08:00ELECTRICAL POWER | ENERGY METER DISCUSSIONS<div class="separator" style="clear: both; text-align: left;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjN8p7I27WOhLq9VR3qsU1PvS-J2_8l5Qu14Wd7rViX4N_3hAdwBA2_ma7-GkATihFi-x3AH6f1ddxTI5hlT6agxETuRtgNvoU0IYf1eRf5jdQYdAQ1OjxmuTBCw2KZNEI7WMPfEVOS8-U/s1600/m.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="energy meter" border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjN8p7I27WOhLq9VR3qsU1PvS-J2_8l5Qu14Wd7rViX4N_3hAdwBA2_ma7-GkATihFi-x3AH6f1ddxTI5hlT6agxETuRtgNvoU0IYf1eRf5jdQYdAQ1OjxmuTBCw2KZNEI7WMPfEVOS8-U/s640/m.JPG" title="" width="640" /></a></div>
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Theory: - </h3>
<div class="separator" style="clear: both; text-align: left;">
Energy meter is an instrument which measures electrical energy. It is also known as watt-hour (Wh) meter. It is an integrating device. There are several types of energy meters single phase induction type energy meter are very commonly used to measure electrical energy consumed in domestic and commercial installation. Electrical energy is measured in kilo watt-hours (kWh) by this energy meter. </div>
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<br /></div>
<h3 style="clear: both; text-align: left;">
Construction: - </h3>
<div class="separator" style="clear: both; text-align: left;">
A single phase induction type energy meter consists of driving system, moving system, braking system and registering system. Each of the systems is briefly explained below. </div>
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<br /></div>
<h3 style="clear: both; text-align: left;">
Driving system: -</h3>
<div class="separator" style="clear: both; text-align: left;">
This system of the energy meter consists of two silicon steel laminated electromagnets. M1 & M2 as shown in fig.1The electromagnet M1 is called the series magnet and the electromagnet M2 is called the shunt magnet. The series magnet M1 carries a coil consisting of a few turns of thick wire. This coil is called the current coil (CC) and it is connected in series with the circuit. The load current flows through this coil. The shunt magnet M2 carries a coil consisting many turns of thin wire. This coil is called the voltage coil (VC) and is connected across the supply it consist of current proportional to the supply voltage. Short circuited copper bands are provided on the lower part of the central limb of the shunt magnet.</div>
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<br /></div>
<div class="separator" style="clear: both; text-align: left;">
By adjusting the position of these loops the shunt magnet flux can be made to lag behind the supply voltage exactly 90° . These copper bands are called power factor compensator (PFC). A copper shading band is provided on each outer limb of the shunt magnet (fc1 &fc2) these band provides frictional compensation.</div>
<div class="separator" style="clear: both; text-align: left;">
<br /></div>
<h3 style="clear: both; text-align: left;">
Moving system: -</h3>
<div class="separator" style="clear: both; text-align: left;">
The moving system consists of a thin aluminium disc mounted on a spindle and is placed in the air gap between the series and the shunt magnets. It cuts the flux of both the magnet forces are produced by the fluxes of each of the magnets with the eddy current induced in the disc by the flux of the other magnets. Both these forces act on the disc. These two forces constitute a deflecting torque.</div>
<div class="separator" style="clear: both; text-align: left;">
<br /></div>
<h3 style="clear: both; text-align: left;">
Braking system: -</h3>
<div class="separator" style="clear: both; text-align: left;">
The braking system consists of a permanent magnet called brake magnet. It is placed near the edge of the disc as the disc rotates in the field of brake magnet eddy current are induced in it. These eddies current react with the flux and exert a torque. This torque acts in direction so that it opposes the motion of disc. The braking torque is proportional to the speed of the disc.</div>
<div class="separator" style="clear: both; text-align: left;">
<br /></div>
<h3 style="clear: both; text-align: left;">
Registering system: -</h3>
<div class="separator" style="clear: both; text-align: left;">
The disc spindle is connected to a counting mechanism this mechanism records a number which is proportional to the number of revolutions of the disc the counter is calibrated to indicate the energy consumed directly in kilo watts-hour (kWh)</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0tag:blogger.com,1999:blog-3250786070166029364.post-44739043567466201972017-01-21T10:10:00.001-08:002017-01-21T10:10:43.529-08:00DC NETWORK THEOREM - ELECTRICAL ENGINEERING BASIC<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGWmxVir9RkyKwiseu2cyqxJbKn8GuEG3uPCZU1r8CP4LE3Vp2kRg1KasYCETc8fS7NhZYONAd64Jjcf3m_pBFqNauSgia-TAx72jfppss777Y1Hds4AMX4sJ3g395msEM1t6NrfkISso/s1600/images.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="609" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgGWmxVir9RkyKwiseu2cyqxJbKn8GuEG3uPCZU1r8CP4LE3Vp2kRg1KasYCETc8fS7NhZYONAd64Jjcf3m_pBFqNauSgia-TAx72jfppss777Y1Hds4AMX4sJ3g395msEM1t6NrfkISso/s640/images.png" width="640" /></a></div>
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<span style="font-size: 12pt; line-height: 115%;"><b><br /></b></span></div>
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<span style="font-size: 12pt; line-height: 115%;"><b><br /></b></span></div>
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<span style="font-size: 12pt; line-height: 115%;"><b>Current</b>: </span><span style="font-family: TimesNewRoman; font-size: 12pt; line-height: 115%;">“Rate of flow of electric charge.”</span></div>
<div class="MsoNormal">
<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;"><b>time<o:p></o:p></b></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Charge<o:p></o:p></span></div>
<div class="MsoNormal">
<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">I </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Coulombs/Sec or Ampere<o:p></o:p></span></div>
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<span style="font-size: 9.0pt; line-height: 115%;">Note:-<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 9.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">1. Direction of current is same as the direction of motion of +Ve charge or opposite to the direction of<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 9.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">motion of –Ve charge.<o:p></o:p></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><br /></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><b>Voltage:</b> “</span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Energy required in transferring a charge of one coulomb from one point to<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">another point.”<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12pt;">Charge(Q)</span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Energy(W)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">V </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Joule/Coulomb or Volts<o:p></o:p></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><br /></span></div>
<div class="MsoNormal">
<span style="font-size: 12.0pt; line-height: 115%;"><b>EMF (Electromotive force):</b> </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">“The EMF of a voltage source is the energy imparted by<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">the source to each coulomb of the charge passing through it.”<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Charge(Q)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Energy(W)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">E </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Joule/Coulomb or Volts<o:p></o:p></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><br /></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><b>Potential Difference:</b> </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">“The pd between two points is the energy required in transferring a<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">charge of coulomb from one point to another point.”<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Charge(Q)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Energy(W)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">pd </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Joule/Coulomb or Volts<o:p></o:p></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><br /></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><b>Voltage drop: </b></span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">“The voltage drop between two points is the decrease in energy required<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">in transferring a charge of coulomb from one point to another point.”<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Charge(Q)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Energy(W)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Voltage drop </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Joule/Coulomb or Volts<o:p></o:p></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><br /></span></div>
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<span style="font-size: 12.0pt; line-height: 115%;"><b>Resistance:</b> </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">“Electric resistance is the property of material which offers opposition to the<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">flow of current and dissipates energy.”<o:p></o:p></span></div>
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<i><span style="font-family: "TimesNewRoman\,Italic"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: "TimesNewRoman\,Italic";">a<o:p></o:p></span></i></div>
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<i><span style="font-family: "TimesNewRoman\,Italic"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: "TimesNewRoman\,Italic";">l<o:p></o:p></span></i></div>
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<i><span style="font-family: "TimesNewRoman\,Italic"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: "TimesNewRoman\,Italic";">R </span></i><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: Symbol; font-size: 12.5pt; line-height: 115%; mso-bidi-font-family: Symbol;">ñ </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Ohm or </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">_ </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">(Law of resistance)<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Where </span><i><span style="font-family: "TimesNewRoman\,Italic"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: "TimesNewRoman\,Italic";">l </span></i><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Length of the wire<o:p></o:p></span></div>
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<i><span style="font-family: "TimesNewRoman\,Italic"; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: "TimesNewRoman\,Italic";">a </span></i><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">cross </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">− </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">sectional area of the wire<o:p></o:p></span></div>
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<span style="font-family: Symbol; font-size: 12.5pt; line-height: 115%; mso-bidi-font-family: Symbol;">ñ </span><span style="font-family: Symbol; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: Symbol;">= </span><span style="font-family: TimesNewRoman; font-size: 12.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">Resistivity or Specific Resistance of the material<o:p></o:p></span></div>
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<span style="font-size: 10.0pt; line-height: 115%;">Note:-<o:p></o:p></span></div>
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<span style="font-family: TimesNewRoman; font-size: 10.0pt; line-height: 115%; mso-bidi-font-family: TimesNewRoman;">1. Resistance also depends on temperature.</span><o:p></o:p></div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0tag:blogger.com,1999:blog-3250786070166029364.post-42079603672308836702017-01-21T09:51:00.000-08:002017-01-21T09:51:09.288-08:00WHAT IS COHESIVE DEVICES? DISCUSSIONS<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqc9WEJQ3sYNDimoGng7albSKKCpPE47acdlqW8IxljB4lsqPX6bP3Znb-53r9OClCjAwZlOJ1WHsIUPRABcZGwshMu-L5k7s7QVBVm2BCBwmTxhC_AzNWKDh-GCfKmwPaRDulcAuBr7g/s1600/AW.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="479" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiqc9WEJQ3sYNDimoGng7albSKKCpPE47acdlqW8IxljB4lsqPX6bP3Znb-53r9OClCjAwZlOJ1WHsIUPRABcZGwshMu-L5k7s7QVBVm2BCBwmTxhC_AzNWKDh-GCfKmwPaRDulcAuBr7g/s640/AW.png" width="640" /></a></div>
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<span style="font-family: inherit;"><span style="font-size: x-large;">C</span>oherence in writing means achieving a consistent relationship among parts. Cohesive devices show the logical relationships between the various parts of an essay as well as between sentences and paragraphs.</span></div>
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<span style="font-family: inherit;">Cohesive devices include: transitional words and expressions, paragraph hooks <o:p></o:p></span></div>
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<span style="font-family: inherit;">cohesive devices are like bridges between parts of your paper<o:p></o:p></span></div>
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<span style="font-family: inherit;">They are cues that help the reader to interpret ideas in the way that you, as a writer, want them to understand cohesive devices help you carry over a thought from one sentence to another, from one idea to another, or from one paragraph to another with words or phrases.</span></div>
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<span style="font-family: inherit;"><o:p></o:p></span></div>
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<span style="font-family: inherit;">cohesive devices link your sentences and paragraphs together smoothly so that there are no abrupt jumps or breaks between ideas.<o:p></o:p></span></div>
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<span style="font-family: inherit;">Cohesive words and phrases are used to link sentences and paragraphs, to show which direction your thought patterns are going, to help the reader accurately follow your train of thought. <o:p></o:p></span></div>
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<span style="font-family: inherit;">They signal the relationships among the various parts of your subject.<o:p></o:p></span></div>
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<span style="font-family: inherit;">Types Of Cohesive Devices</span></h3>
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<span style="font-family: inherit;"><o:p></o:p></span></div>
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<span style="font-family: inherit;"><span style="font-size: large;">T</span>here are several types of cohesive devices, and each category leads your reader to make certain connections or assumptions about the areas you are connecting. <o:p></o:p></span></div>
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<span style="font-family: inherit;">Some lead your reader forward and imply the "building" of an idea or thought, <o:p></o:p></span></div>
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<span style="font-family: inherit;">while others make your reader compare ideas or draw conclusions from the preceding thoughts.<o:p></o:p></span></div>
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<span style="font-family: inherit;">Before, meanwhile, later, soon, at last, earlier, thereafter, afterward, by that time, from then on, first, next, now, presently, shortly, immediately, finally<o:p></o:p></span></div>
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<span style="font-family: inherit;">Likewise, similarly, once again, once more<o:p></o:p></span></div>
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<span style="font-family: inherit;">But, yet, however, although, whereas, though, even so, nonetheless, still, on the other hand, on the contrary As a result, consequently, therefore, hence, for this reason</span></div>
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<span style="font-family: inherit;"><o:p></o:p></span></div>
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<span style="font-family: inherit;">I knew my dieting had gotten out of hand, but when I could actually see the movement of my heart beating beneath my clothes, I knew that I was in trouble. At first, the family doctor reassured my parents that my rapid weight loss was a “temporary phase among teenage girls.” However, when I, at fourteen years old and five feet tall, weighed in at 63 pounds, my doctor…<o:p></o:p></span></div>
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<span style="font-family: inherit;">Transition words are audience cues that help the reader shift from one paragraph to the next. <o:p></o:p></span></div>
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<span style="font-family: inherit;">These connections between paragraphs help the reader see the relationships of the various parts. <o:p></o:p></span></div>
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<span style="font-family: inherit;">Transition words or phrases at the beginning of a new paragraph—such as first, second, next, another, finally, on the other hand, however—show the reader where the essay is going next. <o:p></o:p></span></div>
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<span style="font-family: inherit;">In addition to transition words, writers often tie paragraphs together by repeating a key word or idea from a previous paragraph in the opening sentence of the next paragraph. <o:p></o:p></span></div>
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<span style="font-family: inherit;">This “hooks” the paragraphs together, creating for the reader a logical flow of thought.<o:p></o:p></span></div>
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Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0tag:blogger.com,1999:blog-3250786070166029364.post-3486684470056062322017-01-21T09:44:00.001-08:002017-01-21T09:44:29.795-08:00DC MACHINES AND COMPUTER AIDED DESIGN QUESTIONS FOR PRACTICES<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgnWcPouzNvvTfDbkYywYtAEPXpORzfZ_HDhfNnQmj9LnpaUoe4NwSBpO0Sa2N38aou_9Lv61JhF29HG9-cVQFVWL94ym7phLLfCsPnqqYPi7n9AGDvkamRCozJd0ECbkoFTno6HXj0C8M/s1600/COM.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="425" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgnWcPouzNvvTfDbkYywYtAEPXpORzfZ_HDhfNnQmj9LnpaUoe4NwSBpO0Sa2N38aou_9Lv61JhF29HG9-cVQFVWL94ym7phLLfCsPnqqYPi7n9AGDvkamRCozJd0ECbkoFTno6HXj0C8M/s640/COM.jpg" width="640" /></a></div>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Determine diameter and length for 100 Kw, 230V, 750 rpm, 6 pole dc machine. How the choice is made for selecting pole numbers in a dc machine.<o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Find the suitable number of poles and the dia. of the core of a 400Kw, 550 V, 180 rpm d.c. generator having 92% efficiency. Assume an average flux density in the air gap of about 0.6 wb/m<sup>2</sup> and ampere conductor per meter to be 35000.<o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Explain the use of a digital computer in designing of an electrical machine giving its advantages and limitations. <o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Give Computer Aided Design approaches by the following methods:<o:p></o:p></li>
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<!--[if !supportLists]-->(a)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Analysis<o:p></o:p></div>
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<!--[if !supportLists]-->(b)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Synthesis<o:p></o:p></div>
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<!--[if !supportLists]-->(c)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Hybrid<o:p></o:p></div>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Give concept of optimization as applied to the design of electrical machines. Name some of the optimization techniques employed in design and briefly describe its general procedure.<o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in 63.0pt; text-align: justify;">Explain the design procedure for design of stator of a 3-phase turbo-alternator and write a flow chart to estimate the main dimensions. What statements will have to be changed to make the same program valid for a water wheel generator. <o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">If the design data of a single phase transformer is known, write flow chart for determining % regulation and efficiency at different load currents and power factors.<o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Give design procedure for design of rotor of a wound rotor induction motor.<o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Explain, with flow chart, how the performance of a water wheel generator may be estimated from the design data and what steps can be taken to improve the performance.<o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Write a flow chart to design a d.c. machine and estimate its efficiency.<o:p></o:p></li>
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<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Write a procedure to obtain the leakage reactance of a 3-phase core-type transformer with concentric winding with its relevant computer flow chart and indicate how the value of leakage reactance be controlled by design parameters.</li>
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<br />Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0Central Europe45.398449976304079 9.40429687543.989359476304081 6.822509875 46.807540476304077 11.986083875tag:blogger.com,1999:blog-3250786070166029364.post-57634401777144185222017-01-21T09:39:00.000-08:002017-01-21T09:39:02.322-08:00INDUCTION MOTOR QUESTIONS FOR PRACTICES<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqznwVnlI2WaKZp0mJL0latyGLShM2aWmbNSUT-T0qpaWSO_DD2p6HK2KWxhkb6gI0uecpsXhTa2CqEQzyKKje5mg6PX8BBREtZXjWUiUSzdGTQ_tW3PNss7HB7sxFBu6i67hQfx_74wM/s1600/INDU.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="induction motors" border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhqznwVnlI2WaKZp0mJL0latyGLShM2aWmbNSUT-T0qpaWSO_DD2p6HK2KWxhkb6gI0uecpsXhTa2CqEQzyKKje5mg6PX8BBREtZXjWUiUSzdGTQ_tW3PNss7HB7sxFBu6i67hQfx_74wM/s640/INDU.jpg" title="" width="640" /></a></div>
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<!--[if !supportLists]-->1.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Drive the output equation of a 3-phase induction motor and also explain how the magnetic and electric loading is selected.<o:p></o:p></div>
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<!--[if !supportLists]-->2.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Write down the steps to find out the main dimensions of a 3-phase IM. Also draw a flow chart for it.<o:p></o:p></div>
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<!--[if !supportLists]-->3.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Explain and find out flux density in stator teeth. <o:p></o:p></div>
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<!--[if !supportLists]-->4.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Explain how the rotor is designed of a 3-phase ship ring induction motor. Also draw a flow chart for it.<o:p></o:p></div>
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<!--[if !supportLists]-->5.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Estimate<b> </b>the stator slot leakage reactance for 1-Layer winding.<o:p></o:p></div>
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<!--[if !supportLists]-->6.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Write down step by step how the circle diagram is drawn for an induction motor? <o:p></o:p></div>
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<!--[if !supportLists]-->7.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Calculate the main dimension, turns per phase, Number of conductors, slots, cross-section of the conductor of a 50 KW, 415 volts, 3 phase,, 50 Hz, 1000 RPM, slip ring induction motor. Given B<sub>av</sub> = 0.52T, η= 0.9, pf =0.89 lagging, =32000 ac /m, δ= 5A /mm².<o:p></o:p></div>
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<!--[if !supportLists]-->8.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->A 20-kw, 3-phase, 6-pole, 50-Hz, 400 V delta connected cage rotor induction motor has 54 stator slots, each containing 10 conductors. Design suitable number of rotor slots and determine the value of bar and end ring currents. The machine has efficiency of 85% and power factor 0.85 lagging. Also find the bar and end ring sections, if current density is 6.0 A/mm². Assume rotor mmf as 85% of the stator mmf.<o:p></o:p></div>
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<!--[if !supportLists]-->9.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Describe the significance of B<sub>30</sub> in a 3-phase induction motors. A 75 kw, 3300V, 50 Hz, 8-pole, 3-ph, star connected induction motor has a magnetizing current which is 35% of full load current. Calculate the number of stator winding turns per phase if the mmf required for flux density at 60<sup>0</sup> from the inter polar axis is 500 A. Assume winding factor = 0.95, full load efficiency = 0.94 and full load power factor = 0.86.<o:p></o:p></div>
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<!--[if !supportLists]-->10.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Estimate the main dimensions & air gap length for a 3-phase, 20 HP, 400 V, 6-pole, 50 Hz, 970 RPM induction motor suitable for a star-delta starting. Assume magnetic and electric specific loadings as 0.45 wb/m<sup>2</sup> and 23000 ac/m respectively, ratio of core length to pole pitch 0.85, full load efficiency 0.88 and power factor 0.89.<o:p></o:p></div>
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<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l0 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]--><span style="font-family: "Arial","sans-serif"; font-size: 11.0pt; mso-fareast-font-family: Arial;">11.<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span style="font-family: "Arial","sans-serif"; font-size: 11.0pt;">Estimate the main dimensions, number of radial ducts, number of stator slots, number of turns per phase, conductors per slot and slot dimensions for 7.5 kW, 415 V, 3-phase, delta-connected, 4-pole, 50 Hz squirrel-cage induction motor. The flux per pole is 0.015 Wb. Assume efficiency 85% and power factor as 0.85 lagging.<o:p></o:p></span></div>
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<!--[if !supportLists]--><span style="font-family: "Arial","sans-serif"; font-size: 11.0pt; mso-fareast-font-family: Arial;">12.<span style="font-family: "Times New Roman"; font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span style="font-family: "Arial","sans-serif"; font-size: 11.0pt;">Determine the main dimensions, turns per phase, number of slots, conductor section and slot area of 200 H.P, 3 phase, 50Hz, 400 Volts, 1480 r.p.m. slip ring induction motor. Assume Bav = 0.5 wb/m<sup>2</sup>, ac = 30,000 amp conductor / meter, efficiency = 0.9 and power factor = 0.9, current density = 3.5 amp per mm<sup>2</sup>.<o:p></o:p></span></div>
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<!--[if !supportLists]-->13.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Design a 10 HP, 415 V, 3-phase, 50 Hz, 1440 rpm, squirrel cage induction motor. The machine is to be started by a star delta starter. Assume all suitable data yourself.</div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com1tag:blogger.com,1999:blog-3250786070166029364.post-12604342346651008702017-01-21T09:36:00.001-08:002017-01-21T09:36:36.490-08:00MACHINE DESIGNING - QUESTIONS FOR PRACTICES<div class="separator" style="clear: both; text-align: center;">
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<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->1.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Obtain expression for output equation of a rotating
machine. Apply this for a synchronous, induction and dc machine.<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 9.0pt; text-align: justify;">
<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->2.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Discuss factors affecting size of rotating machine and
how the separation of main dimensions is done.<o:p></o:p></div>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->3.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Explain SCR in synchronous machines.<o:p></o:p></div>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->4.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Find the main dimensions of a 20 MVA, 11kV, 50Hz,
150r.p.m., 3-phase water wheel generator. The average gap density is 0.6 Wb /m²
and ampere conductors per meter are 35,000. The peripheral speed should not
exceed 65 m/s at normal running speed in order to limit the run-away speed.<o:p></o:p></div>
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<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->5.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Give procedure for designing the field system of a
three-phase turbo generator from the given design data. Also indicate how much
excitation power may be required for such a generator of about 100 MW capacity.
<o:p></o:p></div>
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<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->6.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->A 1500 kVA, 3-phase, star-connected, 3300 V, 250 rpm
water wheel generator has the following design data:<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: .5in; text-align: justify; text-indent: .5in;">
Effective
gap length = 7mm<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: .5in; text-align: justify; text-indent: .5in;">
Effective
gap area/pole =
0.075 m²<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: .5in; text-align: justify; text-indent: .5in;">
Winding
factor =
0.955<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: .5in; text-align: justify; text-indent: .5in;">
Field
mmf per pole under rated condition = 7850 A<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: .5in; text-align: justify; text-indent: .5in;">
No.
of field turns/pole = 180<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 24.0pt; text-align: justify;">
The peak value
of fundamental flux density distribution B…= 0.94 T and peak value of the
actual flux density distribution B…=0.9T.<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 24.0pt; text-align: justify;">
The
permissible value of current density in field winding is 3 A/mm². Determine:<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 60.0pt; mso-list: l0 level1 lfo2; tab-stops: list 60.0pt; text-align: justify; text-indent: 30.0pt;">
<!--[if !supportLists]-->(i)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Turns / phase<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 60.0pt; mso-list: l0 level1 lfo2; tab-stops: list 60.0pt; text-align: justify; text-indent: 30.0pt;">
<!--[if !supportLists]-->(ii)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->MMF for air gap<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 60.0pt; mso-list: l0 level1 lfo2; tab-stops: list 60.0pt; text-align: justify; text-indent: 30.0pt;">
<!--[if !supportLists]-->(iii)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Armature
MMF /pole<o:p></o:p></div>
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<!--[if !supportLists]-->(iv)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Field
current<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 60.0pt; mso-list: l0 level1 lfo2; tab-stops: list 60.0pt; text-align: justify; text-indent: 30.0pt;">
<!--[if !supportLists]-->(v)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Sectional area of field conductor. <o:p></o:p></div>
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<br /></div>
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<!--[if !supportLists]-->7.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Design the suitable values of diameter and length of a
75 MVA, 11 KV, 50 Hz, 3000 rpm, 3-phase star connected alternator. Also
determine the value of flux, conductor per slot, no of turns per phase, and
size of armature conductor. Given<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 1.5in;">
Average gap density = 0.6 T<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 1.5in;">
Amp conductor per m = 50,000<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 1.5in;">
Peripheral speed = 180 m/s<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 1.5in;">
Current density = 6 A/m<sup>2<o:p></o:p></sup></div>
<div class="MsoNormal" style="margin-left: 1.5in;">
<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->8.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->Calculate the diameter, core length, number of
conductors of the stator, size of conductor, number of stator slots of a 30
MVA, 11KV, 3000 r.p.m. 50Hz star connected turbo alternator. Assume suitable
data:<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 27.0pt; text-align: justify;">
Bav =0.55
Wb/m², ac =55000 A/m, Kw = 0.955,<o:p></o:p></div>
<div class="MsoNormal" style="margin-left: 27.0pt; text-align: justify;">
Peripheral
velocity = 160 m/s.<o:p></o:p></div>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; text-align: justify;">
<br /></div>
<div class="MsoNormal" style="margin-left: 27.0pt; mso-list: l1 level1 lfo1; tab-stops: list 27.0pt; text-align: justify; text-indent: -.25in;">
<!--[if !supportLists]-->9.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;">
</span><!--[endif]-->If two synchronous machines running at the same speed
and having the same number of poles, the physical dimensions are in the ratio 3
: 2. Compare the outputs, armature copper losses and iron losses in the two
machines. Assume specific magnetic loading and current density to be same for
both the machines. </div>
<br />Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com1tag:blogger.com,1999:blog-3250786070166029364.post-66045294369549598222017-01-21T09:34:00.000-08:002017-01-21T09:34:14.873-08:00ELECTRICAL MACHINES DESIGN QUESTIONS FOR PRACTICES<div class="separator" style="clear: both; text-align: center;">
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<br />
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="10" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="text-align: justify;">Find the amount of cooling air required in m<sup>3 </sup>per second at the inlet temperature of 25<sup>O</sup>C for a 25000KVA alternator working at full load. The efficiency is 96% and the power-factor is 0.87. The temperature of air coming out of machine is 50<sup>O</sup>C. Determine also the amount of hydrogen required with the same data.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="11" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="text-align: justify;">Discuss, briefly, about the “Frame Size” and “Standard Frames”.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="margin-left: 0.5in; text-align: justify;">
<br /></div>
<ol start="12" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="text-align: justify;">Explain heating and cooling process of electrical machines also define heating & cooling time constants.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="13" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="text-align: justify;">What do you understand by the term “Impregnation of winding”?<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="margin-left: 0.25in; text-align: justify;">
<br /></div>
<ol start="14" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="text-align: justify;">Does the selection of current density Amp /mm² in the design of electrical machines, depend on duty-cycle of the respective machine? Explain in brief.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<br />
<ol start="15" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="text-align: justify;">Justify the statement, “By exceeding the rate of cooling, the overload capacity of an electrical machine can be enhanced.”</li>
</ol>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com2KU Circular Rd, Karachi, Pakistan24.9391508 67.1134758000000624.9391508 67.11347580000006 24.9391508 67.11347580000006tag:blogger.com,1999:blog-3250786070166029364.post-52102588848107316532017-01-21T09:32:00.000-08:002017-01-21T09:32:24.528-08:00ELECTRICAL MACHINE DESIGNING QUESTIONS ANSWERS - PRACTICES<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9E0zHy60Hd0PBjZIoEYKXt30tVqApsVhbv6L41BZuRdacSJzdQA-rtOkIw6J2ntthfVA4tgEu7CfAty_bWa_Outcg-XDmWibu2jhuxaTtExfF0ND43pvGQ_-wSogyVUcNgh8gxnmw5Ws/s1600/DES.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="DESIGNING OF MACHINES" border="0" height="492" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj9E0zHy60Hd0PBjZIoEYKXt30tVqApsVhbv6L41BZuRdacSJzdQA-rtOkIw6J2ntthfVA4tgEu7CfAty_bWa_Outcg-XDmWibu2jhuxaTtExfF0ND43pvGQ_-wSogyVUcNgh8gxnmw5Ws/s640/DES.jpg" title="" width="640" /></a></div>
<div style="text-align: justify;">
<br /></div>
<div style="text-align: justify;">
<br /></div>
<div style="text-align: justify;">
<br /></div>
<ol start="1" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Discuss basic concepts of design giving limitations
in design.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="margin-left: .25in; text-align: justify;">
<br /></div>
<ol start="2" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">What is understood by the terms, Standards and
Standardization as applied to the design of electrical machines? Explain
their importance.<o:p></o:p></li>
</ol>
<div class="MsoListParagraph">
<br /></div>
<ol start="3" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">What is understood by the term, “Specifications? Write
down specifications for transformers and induction motors.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="margin-left: .5in; text-align: justify;">
<br /></div>
<div class="MsoNormal" style="margin-left: .25in; text-align: justify;">
<br /></div>
<ol start="4" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">What are the modern trends in design and
manufacturing techniques giving their relative advantages.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="5" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Give a classification of insulating materials used in
electrical machines in context of permissible temperature rise.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="6" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Name a few insulating materials used in a transformer
and give their temperature limits.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="7" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Give modes of heat dissipation in electrical machines
and obtain temperature rise-time curves.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="8" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Describe the types of enclosures used for induction
motors and their effect on cooling.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="9" style="margin-top: 0in;" type="1">
<li class="MsoNormal" style="mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Explain radial, axial, induced and forced cooling as
applied to electrical machines. What is direct cooling and how the
quantity of cooling medium estimated.<o:p></o:p></li>
</ol>
<div class="MsoNormal" style="text-align: justify;">
<br /></div>
<ol start="15" style="margin-top: 0in;" type="1">
</ol>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com3Mumbai, Maharashtra, India19.0759837 72.87765590000003619.0759837 72.877655900000036 19.0759837 72.877655900000036tag:blogger.com,1999:blog-3250786070166029364.post-77343532667818518012017-01-21T09:27:00.002-08:002017-01-21T09:28:44.865-08:00INDUCTION MOTORS QUESTIONS ANSWERS<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj3VnjkpVXERGQLAMxsnPkXQ5JFzE3hoY-TEZc13IOYuSiYQMDaBamJZ9MX2YmHS495dF9oCctAepI3botLJwxE4tYnjbYKrVe_N9mZ2F1-qwh68-4gqhajMySVSs-Siu9MHVLiwwPtIHM/s1600/ind.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img alt="induction motors" border="0" height="480" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj3VnjkpVXERGQLAMxsnPkXQ5JFzE3hoY-TEZc13IOYuSiYQMDaBamJZ9MX2YmHS495dF9oCctAepI3botLJwxE4tYnjbYKrVe_N9mZ2F1-qwh68-4gqhajMySVSs-Siu9MHVLiwwPtIHM/s640/ind.jpg" title="" width="640" /></a></div>
<div class="MsoNormal" style="margin-left: 2.5in; text-indent: .5in;">
<br /></div>
<br clear="ALL" />
<br />
<div class="MsoNormal" style="margin-left: .75in; mso-list: l1 level1 lfo1; tab-stops: list .75in; text-indent: -.5in;">
<!--[if !supportLists]--><span lang="FR">1.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">Explain construction and working principle of a 3-phase indcuiton motor.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-left: .25in;">
<br /></div>
<div class="MsoNormal" style="margin-left: .75in; mso-list: l1 level1 lfo1; tab-stops: list .75in; text-indent: -.5in;">
<!--[if !supportLists]--><span lang="FR">2.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">Explain the terms slip, slip frequency, wound rotor and cage rotor.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-left: .25in;">
<br /></div>
<div class="MsoNormal" style="margin-left: .75in; mso-list: l1 level1 lfo1; tab-stops: list .75in; text-indent: -.5in;">
<!--[if !supportLists]--><span lang="FR">3.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">Draw and explain the torque-slip & torque-speed charactoristics of a typical 3-phase induction motor. Mark the starting torque and maximum troque on the daigram so drawn.<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-left: .25in;">
<br /></div>
<div class="MsoNormal" style="margin-left: .75in; mso-list: l1 level1 lfo1; tab-stops: list .75in; text-indent: -.5in;">
<!--[if !supportLists]--><span lang="FR">4.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">Explain the terms air-fap power P<sub>g</sub>, inernal mechanical power developed and shaft power P<sub>sh</sub>. How are these terms related with each others. Hence show that :<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-left: .75in;">
<span lang="FR">P<sub>g</sub> :Rotor ohmic loss : P<sub>m</sub> =1 :s (1-s)<o:p></o:p></span></div>
<div class="MsoNormal" style="margin-left: .75in;">
<br /></div>
<div class="MsoNormal" style="margin-left: .25in;">
<br /></div>
<div class="MsoNormal" style="margin-left: .75in; mso-list: l1 level1 lfo1; tab-stops: list .75in; text-indent: -.5in;">
<!--[if !supportLists]-->5.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->A 3-phase induction motor runs at 1140 rpm at full load when supplied with power from a 60 Hz, 3-phase line calculate <o:p></o:p></div>
<div class="MsoNormal">
(i) No of poles.<o:p></o:p></div>
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(ii) Slip at full load.<o:p></o:p></div>
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<!--[if !supportLists]-->(iii)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Frequency of rotor voltage.<o:p></o:p></div>
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<!--[if !supportLists]-->(iv)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Speed of rotor field with respect to rotor.<o:p></o:p></div>
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<!--[if !supportLists]-->(v)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Speed of rotor field with respect to stator and stator field.<o:p></o:p></div>
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<!--[if !supportLists]-->(vi)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->Speed of rotor at a slip of 10% and rotor frequency at this speed.<o:p></o:p></div>
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<!--[if !supportLists]-->(vii)<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span><!--[endif]-->If the applied voltage per phase is 230 V, find th0 rotor induced emf at stand still and at 10% slip, with stator to rotor turn ration of 1: 0.5<o:p></o:p></div>
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(Ans: - (i) 1200 rpm, (ii) 5% (iii) 3 Hz (iv) 60 rpm (v) 0 rpm (vi) 1080 rpm, (vii) 11.5 V)<o:p></o:p></div>
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<!--[if !supportLists]--><span lang="FR">6.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">A 6-pole, 3-phase indcution motor develops 30 hp including 2 hp mechanical losses at a speed of 950 rpm on 550 V, 50 Hz mains. The power factor is 0.88 lagging. Calculate (i) slip (ii) torot copper loss (iii) total input if stator losses are 2 kW (iv) efficiecny (v) line current. (Ans : - (i) 0.05, (ii) 1161 Watts, (iii) 20594 Watts, (iv) 81.64% (v) 30 A)<o:p></o:p></span></div>
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<!--[if !supportLists]--><span lang="FR">7.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">Explain construction and principle of operation of 1-phase induction motor.<o:p></o:p></span></div>
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<!--[if !supportLists]--><span lang="FR">8.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">Why single phase induciton moto is not self starting ?<o:p></o:p></span></div>
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<!--[if !supportLists]--><span lang="FR">9.<span style="font-size: 7pt; font-stretch: normal; font-variant-numeric: normal; line-height: normal;"> </span></span><!--[endif]--><span lang="FR">What are the different methods of statring a single phase induction motors and what are the diffenet types of 1-phase induction motors ?</span> </div>
Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com0Dhaka, Bangladesh23.810332 90.41251809999994323.577844499999998 90.089794599999948 24.0428195 90.735241599999938tag:blogger.com,1999:blog-3250786070166029364.post-37600076047997362662017-01-21T08:55:00.002-08:002017-01-21T08:55:50.047-08:00DC MACHINES AND SYNCHRONOUS MACHINES - QUESTIONS FOR PRACTICES<div class="separator" style="clear: both; text-align: center;">
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<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Explain construction and working principle of dc machines with the help of a neat diagram. Drive an emf equation for the same. What is back emf?<o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">What are the different efficiency associated with dc generator and dc motors explain? <o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">Drive an expression for torque in case of dc machine. <o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">A d.c. generator has an armature emf of 100 V when the useful flux per pole is 20 mWb, and the speed is 800 rpm. Calculate the generated emf (i) with the same flux and a speed of 1000 rpm, (ii) with a flux per pole of 24 mWb and a speed of 90 rpm. (Ans.:- (i) 125 V, (ii) 135 V)<o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">An 8 pole dc generator has 500 armature conductors and a useful flux of 0.05 Wb. What will be the emf generated, if it lap connected and runs at 1200 rpm? What must be the speed at which it is to be driven to produce the same emf, if it is wave wound? (Ans.:- 500V, 300 rpm)<o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">A 4 pole dc shunt generator with lap connected armature has field and armature resistance of 80 Ω and 0.1 Ω respectively. It supplies power to 50 lamps rated for 100 volts, 60 watts each. Calculate the total armature current and the generated emf by allowing a contact drop of 1 V per brush. (Ans.:- 26 A, 104.6 V)<o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;"> A d.c. shunt machine connected to 230 V supply has resistance of armature as 0.115 Ω and of field winding as 115 Ω. Find the ratio of the speed as a generator to the speed as a motor with the line current in each case being 100 A. (Ans.:- 1.1052:1)<o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">A d.c. shunt motor draws 10 A at no load from 230 V mains and runs at 1500 rpm. At full load, armature current is 100 A and speed is 1470 rpm. Armature resistance of the motor is 0.1 Ω and field current negligible. Find (a) back emf at no – load and full load (b) speed at which armature should be run to make it deliver 100 A at 220 V as a generator. Assume same flux as with motor operation at full load of 10 A. (Ans.:- (a) 229 V , 220 V (b) 1536.8 rpm)<o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">A 200 V dc series motor runs at 500 rpm when taking a current of 25 A. The resistance of the armature is 0.5 Ω and that of the field is 0.3 Ω. If the current remains constant, calculate the resistance necessary to reduce the speed to 250 rpm. (Ans.:- 3.6 Ω)<o:p></o:p></li>
<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;">A d.c. series motor has an armature resistance of 0.12 Ω and field resistance of 0.08 Ω. The supply voltage across the motor terminals is 230 V. Determine the back emf and power developed by the motor when line current drawn by motor is 30 A. (Ans.:- 224 V, 6.72 kW)<o:p></o:p></li>
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<li class="MsoNormal"><span lang="FR">What are the different types of synchornous machines ? Explain the principle of operation of a 3-phase synchronus motor. Why it is not self starting. <o:p></o:p></span></li>
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<li class="MsoNormal"><span lang="FR">Why the field winding of synchronus generators is placed on rotor.<o:p></o:p></span></li>
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<li class="MsoNormal" style="margin-top: 6.0pt; mso-list: l0 level1 lfo1; tab-stops: list .5in; text-align: justify;"><span lang="FR">Draw and explain V-curve for synchronous motor</span></li>
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Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com2tag:blogger.com,1999:blog-3250786070166029364.post-62197189589636303992017-01-20T23:31:00.001-08:002017-01-20T23:31:27.778-08:00NON LINEAR SYSTEM AND LINEARIZATION - MODERN CONTROL SYSTEM - ELECTRICAL CONTROLLING ENGINEERING<div class="MsoNormal">
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1. Describe the process of linearization by small signal analysis. <o:p></o:p></div>
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2. Linearize following non-linear equation with equilibrium state x<span style="font-size: 7.0pt; line-height: 115%;">0</span>=0 <o:p></o:p></div>
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<span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";"> </span></div>
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<span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";"> 𝑥̇=𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">2 </span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">𝑥̇</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">2</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">=𝜇(1−𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">2</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">)𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">2</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">−𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">1 </span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">𝜇>0 <o:p></o:p></span></div>
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Also check its stability <br /><br /><o:p></o:p></div>
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3. The state equation of a nonlinear system are given below. Determine all points of equilibrium and investigate the stability in the neighbourhood of these points <o:p></o:p></div>
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<span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";"> 𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">1</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">̇=𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">2 </span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">𝑥̇</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">2</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">=−𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">12</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">−𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">22</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">−2𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">1</span><span style="font-family: "Cambria Math","serif"; mso-bidi-font-family: "Cambria Math";">−2𝑥</span><span style="font-family: "Cambria Math","serif"; font-size: 8.0pt; line-height: 115%; mso-bidi-font-family: "Cambria Math";">2 <br /><br /><o:p></o:p></span></div>
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4. Derive the describing function of following <o:p></o:p></div>
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a. Ideal relay <o:p></o:p></div>
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b. Practical relay <o:p></o:p></div>
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c. Combination of dead zone and saturation <o:p></o:p></div>
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d. Backlash <o:p></o:p></div>
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5. How stability is decided by describing function method? <o:p></o:p></div>
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6. Determine stability of following system by describing function method. The describing function of nonlinearity is given by <o:p></o:p></div>
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Anonymoushttp://www.blogger.com/profile/09505042379468788222noreply@blogger.com1