50/51 G on breakers larger than 1200A

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Electriman

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Are we required per NEC to have 50/51 G on every breaker that is greater or equal to 1200A per NEC or is it only for service disconnect?
 
210.13 Ground-Fault Protection of Equipment. Each branchcircuit
disconnect rated 1000 A or more and installed on solidly
grounded wye electrical systems of more than 150 volts to
ground, but not exceeding 600 volts phase-to-phase, shall be
provided with ground-fault protection of equipment in accordance
with the provisions of 230.95.
Click to expand...

215.10 Ground-Fault Protection of Equipment. Each feeder
disconnect rated 1000 amperes or more and installed on solidly
grounded wye electrical systems of more than 150 volts to
ground, but not exceeding 600 volts phase-to-phase, shall be
provided with ground-fault protection of equipment in accordance
with the provisions of 230.95.
Click to expand...

230.95 Ground-Fault Protection of Equipment. Ground-fault
protection of equipment shall be provided for solidly grounded
wye electric services of more than 150 volts to ground but not
exceeding 1000 volts phase-to-phase for each service disconnect
rated 1000 amperes or more.
Click to expand...

So what do you think?

BTW, it says 1000 A in these provisions, not 1200 A.
 
Electriman said:
Are we required per NEC to have 50/51 G on every breaker that is greater or equal to 1200A per NEC or is it only for service disconnect?
Click to expand...
The smart-ass answer would be “No” because it’s 1000A, not 1200A...

Also, “50/51G” is a bit ambiguous. 50 is just Instantaneous Trip, which is in all breakers, 51 is timed over current trip. “G” is for Ground Fault so 51G is Ground Fault timed overcurrent. But did you mean 50G/51G, then that is GF Instantaneous and GF timed over current, in which case it’s either or both as far as the NEC is concerned.
 
petersonra said:
So what do you think?

BTW, it says 1000 A in these provisions, not 1200 A.
Click to expand...

Yes I meant 50G/51G. Sorry for confusion.

My understanding from those articles is that any breaker that is rated than 1000A has to have ground fault protection. We can use either or both of 50G/51G.

Do you understand it the same way?
 
Yes, basically. There are exceptions to the BRANCH application, for example if the breaker is part of a listed motor controller assembly, you don’t need the GF in the breaker if the ASSEMBLY has it somewhere; for example a solid state overload relay with GF trip, or most VFDs. And similarly with the feeder and service applications, you can have an external GF relay that powers a shunt trip on the breaker or, if the case may be, a Pringle Switch (bolted pressure fused disconnect), meaning it doesn’t have to be IN the breaker. But it’s far easier to go with the built-in GF trip.
 
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