Hello All,
Does anyone know the history behind lighting panels that were ground fault protected? These are mid 1970 panels.
I have always assumed it was due to magnetic balasts tending to leak current. I do not think it was ever a code but not sure.
With everything going to electronic I plan on defeating or replacing the shunt trip on the main breaker.

Thanks
Jeff

Greco:
Welcome back; long time with no posts here.

Are you sure it's GF and not an 'old' system for lighting controls?

I've been 'around' since before '70s and have not encountered any GF on a lighting panel. I've seen a bad ballast trip a GF on main CB's with GF protection (NEC Mandatory), but not any dedicated lighting panels with GF.

Thanks Hotline,

I have been checking the board from the days of Bennie and SDS's. I don't like to use work time to post and I have dial up at home but this is work related. Yes it is GF, 400 amp. It may have been custom made we had deep pockets back then. Over the years we would have an occasional main trip due to a faulted balast, we would repair it and move on. This last one created paper work for me so it is time lose the GF. I just wanted to see if anyone knew anything about them.
Thanks,

Jeff

John,


Maybe it is GFPE and not GFCI. I have seen large frame equipment with GFPE and I also saw where 1 electrician knocked out a 1600 amp main when he shorted out a ballast. The GFPE was set too low.

Harold:
Yes, I only said 'GF', as I was eluding to the required GF (230.95) GFPE.

The OP didn't directly include "CI" or "PE", but I should have. (Two demerits for me) LOL

I also had a few ballasts take out the GFPE mains, one of which was very embarassing!

John,

That is why when I do my inspections, I ask the EC to make sure that the GFPE is set properly. They usually give me a letter stating that they or the manufacture's company rep. has the proper setting on the breaker.

Harold:
That's SOP for me also.

Thanks for the intrest guys,

Yes it is GFPE. I will assume no one has seen these. Any ideas on why they did it? Mid 1970ish. I will be removing the GFPE, I just wanted to check and see if anyone knew the history.

Jeff

Greco:
I have to go with it being a design issue. You mentioned that "deep pockets" were available.

On a 400 amp panel, it is not now, nor was in the past a NEC requirement. As to the purpose it may have served, additional safety for the installation? I've seen a lot of 'fried' old ballasts over my years, but can't remember any additional damages

Thanks Hotline,

That is pretty much what I was thinking. I guess when things are working I don't question design too much.

Jeff