Wednesday, 25 January 2017


Circuit Breakers of differents poles.
Circuit Breakers of differents poles.

MCB (Miniature circuit breaker)

  • The characteristics of miniature circuit breaker are below,
  • MCB rated current is not more than 100 A. means the current limit (or current rating) is maximum 100A).
  • Trip characteristics are normally meant not adjustable.
  •  MCB operation is thermal based or thermal-magnetic.

MCCB (Moulded case circuit breaker)

  • The characteristics of Moulded case circuit breaker are below,
  • The current rating of MCCB is from 101 A to 1000 A.
  •  The Current of a trip (switch off the circuit) may be adjustable, means current rating we can adjust in MCCB.
  • MCCB operates in thermal or thermal-magnetic operation.

ACB (AIR Circuit Breaker)

  • The characteristics of ACB (Air Circuit Breaker) are below.
  • The current rating of ACB (Air circuit breaker) is from 1001 A to 10000 A.
  • Trip characteristics of Air Circuit Breaker (ACB) often fully adjustable including configurable trip thresholds and delays.
  • 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.

VCB (Vacuum Circuit Breaker)

  • Some important characteristics of Vacuum circuit breaker are below,
  • The VCB (Vacuum circuit breaker) current rating is up to 3000 Amperes.
  • The main characteristics of vacuum circuit breaker are, it interrupts the arc in a vacuum bottle.
  • These can be applied at up to 35 thousand volts.
Is there any other you know, Share with us from below comment box.



  1. Is there Any other cIRCUIT breaker with higher rating than the VCB? for power system?

  2. Yes The Air Blast C.B. (A.B.C.B.) M.O.C.B. and SF6 C.B. having higher ratings than the VCB. For voltages above 220 kV SF6 C.B. are used

  3. This is very nice blog and good information for MCCB Circuit Breaker MCCB Circuit Breaker