Arc Flash Energy Reduction Switch (ARMS)

[bikeman1]

Im looking at implementing a maintenance switch activated only while work is being conducted on or near the switchboard which activates an instantaneous element. this will reduce arc flash energy while work is being conducted.The current overcurrent relay is a GEC Alstom mcgg 62

http://www.electricalmanuals.net/files/RELAYS/ALSTOM/MCGG/R6054X.pdf.

Does anyone know how this could be retrofitted, my current thought is to activate the instantaneous element and place the switch on the output for the instantaneous element of the relay.

any help would be greatly appraciated.

 

[wbd]

I assume that you have had an arc flash study done so that you know the arcing current. Other than that, a couple of thoughts:

1. If this is a true switchboard, then you cannot take credit for the main breaker in the switchboard for protecting in an arc flash event. Therefore the CTs and relay will have to be on the feeder breaker to this switchboard.

2. If it is switchgear, the construction may be such that main breaker could provide arc flash protection, then the relay could be installed there and trip that breaker.

3. If an arc flash study was done, was the coordination looked at to see if a permanent trip change could be implemented?

4. More details of the equipment may help spur other ideas from the forum.

 

[bikeman1]

sorry its actually a mcc not a switchboard, acing current is about 17kA from memory.

1/2) the segregation of the mcc is very good, my understanding is that this will mean that the main cb will provide arc flash protection, is this correct?
3)looking into this as well
4) what more info would be beneficial?

Cheers