Difference Between 3P MCCB and TPN MCCB

The latter also includes the neutral, effectively making it 4-pole.

See this previous thread: http://cr4.globalspec.com/thread/53968 for mre detail.

- MS

dear,

MCCB = Moulded Case Circuit Breakers , normally having high breaking capacity- 30ka to 70 KA, Ics = Icu, compact, but bulkier, carrying high electrical energy.

Ranges available are up to 1250 Amp.

MCB = Miniature circuit breaker, normally low current breaking capacity, 10-12 ka, very miniature by its name, carrying low currents may be of lighting , & small motors .

Ranges available are up to 100 Amp max.

In 3-Pole MCCB, switching & protection is effected in only three phases and the neutral is not part of the MCCB. In TPN MCCB, Neutral is part of the MCCB as a seperate pole but without any protective release in the neutral pole (i.e.) neutral is only switched but has no protective element incorporated. In 4-Pole MCCBs the neutral pole is also having protective release as in the phase poles.