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Circuit Breaker - Spring discharge and

Circuit Breaker - Spring discharge and

Circuit Breaker - Spring discharge and

(OP)
I have probably seen this hundreds of times, but can't seem to remember: does the Spring in a breaker charge when the breaker is opened, and discharges when you close it. and/or it charges everytime no matter if it was opened or closed?

I recall hearing the spring compressing (charging)after I open the CB, but don't remember any charging after I close it. Its probably a silly question, but please do clarify.

Also, on one of the AREVA breakers, I have a "spring status" contact, instead of a "spring discharge alarm" contact that I usually use for alarming. So how can I use that "spring status" or what exactly is it, other than the obvious 'status'
Thanks.

RE: Circuit Breaker - Spring discharge and

Which springs? What typeof breaker?

Typically the charging spring on an EO breaker will charge after the close cycle is complete.  

RE: Circuit Breaker - Spring discharge and

(OP)
Its a 69KV SF6 Circuit breaker from AREVA.

RE: Circuit Breaker - Spring discharge and

Might be different, I don't deal with those very often. Maybe someone else with more experience with them will say differently.  

RE: Circuit Breaker - Spring discharge and

Utility breakers typically store energy in a main spring which is charged when the breaker is closed.  The closing operation charges a separate mechanism which stores energy for tripping.  You will usually hear the spring charge motor run after a close operation, not after a trip.

Becasue the breaker is typically designed to store energy for an O-C-O cycle, it has to have reserve power for a second trip and open without charging, since spring rewinding may take several seconds, and first reclose events are usually much to fast for a recharge.

The mechanism is designed so the the trip energy is stored by the act of closing the breaker so guaranteeing that if you can get the breaker closed, even manually, the energy is then stored to get it opened again.  There is nothing that prevents rewinding after an open, but it is not usual as the main spring is typically not depleted by that trip.

I don't have an ANSI standard set at hand, but I suspect that spring charge alarm conditions are mandated.  However, if the manufacturer provides a B contact on discharge rather than an A contact, it could be labelled as status.  I suspect that this is just a sense flip.

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