Answer / j. a

Actually the ACB is abbreviation of Air circuit breaker,
which is normally used for LV switchgears and high current
(normally more than 400A). The switching contacts are
operating in the air. MCCB is abbreviation of moulded case
circuit breker which is normally used for switching of load
less than 630 A.

Answer / satya dev

As per IE Rule Below than 1000 Amp. Load we can use MCCB &
Above than 1000 Amp. Load we must be use ACB.another reason
is the Range of Short Ckt Capacity of ACB is Greater Than
the MCCB.

Answer / govind

the 3rd answer is correct

Answer / mahadikpramod

1)Differencfe between ACB & MCCB is mainly,ACB we can use
for large load and MCCB we can not.

Answer / srabon1059

ACB(Air circuit breaker):

1.ACB provide over load,under voltage and short ckt protection.
2.mainly used in industrial are.



MCCB(oulded case circuit breker):

1.Provide over load ,short ckt protection.

Answer / aravind

ACB :Air circuit breaker is available from 400A to 6300A .
They are generally used for O/L,S/C,E/f and metering
protection.

The breaking capacity is generally 35kA/50kA/60/75KA

MCCB:Moulded case circuit breaker is available from 32A to
1600A.
They offer all the protection as offered by ACB.

However MCCB are compact when compared to ACB for
respective ratings.

MCCB are difficult to repair and life is less when compared
to ACB.

Answer / mohammed yousuf khan

ACB stands for Air Circuit Breaker whereas MCCB stands for Moulded Case Circuit Breaker. Generally MCCBs are used for loads upto 630A but if the load is higher say beyond 630A then the ACBs are used.

1)Also ACB is long lasting when compared to MCCB.

2)The switching contacts of ACB operate in air, whereas the switching contacts of MCCB operate in a case. Hence the name ACB & MCCB.

3)Apart from Overload, Short Circuit & Earth fault protection, other protections such as Under voltage protection can be achieved using ACB.

4)MCCBs are very compact, whereas ACBs are large in size when compared to MCCBs.

5)MCCBs needs to be replaced after a certain operations but ACBs can be re-used with little maintenance, as the spares are easily available for ACBs such as Contacts,arc chute etc...

What is the actual formula for transformer short circuit test? below i given rating of the transformer.. 1000KVA, pri 11KV, Pri amp 56A. %Z 5.95..

2 Answers  

why is only third harmonics is dangerous for electrical equipments?

3 Answers  

how to select the automotive wire size by mathematical calculation. for xenon headlamp with ballast. the ballast given data voltage 10-17v,current permenant 6amp, run up phase is 15amp, peak at swicth on max 400micro sec is 40amp.the sum of cable resistance is 150mohm.please provide referenc document if any for relating the peak at switch on current,time & wire wire size

0 Answers   Tyco,

hi frnz,can somebody give me any project work? i am a 2nd year student & interested in practical works...plz give me some projects

0 Answers  

How relay works, reverse relay, master relay, os relay, earth fault relay and what is its setting point

0 Answers   cpgn,

What will happen if the d.c. Machine is operated below rated speed?

0 Answers  

how to identify the failer of igbt

0 Answers  

What is the technical name of Transformer Oil ?

17 Answers   Bhel, Don Bosco, Lanco,

What we mean by vintage of an engine+Generator?

0 Answers  

Suppose am having the PF value .8, so how can we say that is it lagging or leading?

11 Answers   Bhel,

what is RFID? thire application;

0 Answers  

In Delta connected capcitor bank, One bank failed due to some problem. Can we connect Open delta capacitor bank to 3 phase motor. The motor voltage rating is 6.6KV. IF yes what changes will happen?

1 Answers