No neutral

[cornbread]

I'm working on an old wharehouse that has 277V lighting installed. Here is the problem, the lighting panel SQD NQOD has a 480v feed with ground pulled to it. Note no neutral was pulled to the cabinet. It looks like they tied the neutral and ground at the panel. The installation was probably some 40 years ago.

My question to this forum is: Was this a standard practice 40 years ago?
: if so it such an installation grandfathered?

I told the owner if it was my building I would install a Xfmer to derive a proper neutral.

 

[Minuteman]

Is that the main service or a separately derived service?

 

[cornbread]

It basically the main service. The wharehouse has a small MCC and this panel is fed from that MCC.

 

[roger]

There is another problem with the set up, the NQOD panel is being used outside it's listing, NQ panels and QO breakers are for 250 volts and below.

Roger

 

[Sierrasparky]

I wonder how that got passed?

 

[Pierre C Belarge]

This was not a permitted install 40 years ago.

In regards to it passing inspection, it may not have been inspected.
Subpanels are installed many times without inspection.

I am looking at a job on private property that has a large generator and firepump installation that was installed without permits and most likely never inspected.

 

[augie47]

You obviously can't get around the NQOD problem, but were the ground the only problem, IF the panels are connected by metallic conduit, you could isolated the conductor, making it a neutral and let the conduit be the ground (noting 250.92 in regard to eccentric knockouts, tec)

 

[cornbread]

My bad the panel is a NH1B.

 

[cornbread]

So was this practice ever OK?????????

 

[LarryFine]

So was this practice ever OK?????????

Only on the line side of the main disconnect.