Remote Control of MCCB (Molded Case Circuit Breakers)

These questions makes me wonder if you understand at all the topic. Hundreds of ampere circuit breakers are specialty equipment protection devices that require a qualified individual to manipulate safely, let alone design or market them. The design specific need for auxiliary contacts on any circuit breaker is that there are at least three states any circuit breaker can be in; ON, OFF and TRIPPED. Frequently it is necessary to remotely know the state of a breaker regardless of primary power being provided.

Hi ,

thanks for your reply !

yes I am not a specialist ..but I will progress

maybe my asking was not totaly clear , so let me explain :

I checked manufacturers webs , have some contacts ,but following these have some doubts ;

looking to the fact that in the MCCB (LV Power) circuit breakers offers : the auxiliary contacts are in most of case "optional µswithes) ; I just wish to obtain some statistical estimate , about the average number of "auxiliary contacts" really used per MCCB 's ;

• for smaller one's MCCB ( continuous current like 100 Amps ) :

>>> can it be in average 1 or 2 auxilliary contacts used ( trip & contact detection) ?

• for bigger on's MCCB ( continuous current from 250 like to 800 Amps :

>>> can it be in average 3 to 6 ? (trip , 3 contact detection, belt ...?)

I just wish to have some answers from several industrial users , also from manufacturers ( employees working in the field )

We are not a homework cheat site.

There are thousands of web sites that will give you the answers you seek.

That's how you learn. Having someone give you the answers is not getting g an education.

Read manufacturers' catalogs.

Aux contacts needed on a MCCB, is in our case (we build controls for industrial process skids) just one, although we like a backup and always have them send 2. We do motors in the 5 to 30 HP range typically. We monitor this with a DI in the PLC rack to confirm the motor circuit is on, before allowing process operation, and to alert an alarm if it trips. That is just our particular set of required inputs in our particular programming choice for a our process control.

The problem with the question you asked is as noted above - "our particular programming choice." Others may vary - I don't get to see other programs for process skids built by other companies.

I believe, as others have not, that this is what you were asking for. Very hard to Google that kind of answer.