Two Pole GFCI Breakers For Vintage 3 Wire 240/120 Single Phase Commercial Building

[dpwell]

The only bar in town recently changed hands and is on a shoestring budget. We're trying to help them out. The garbage truck caught the 200 AMP single phase 124TB B-Line meter panel and jammed the cover into the meter socket bussing with arcing ensuing. We pounded the enclosure straight and screwed the cover back on, but found a chunk of black plastic that is mostly likely a piece of the meter socket base. The utility has a locking ring on the meter, but even without it we would be reluctant to pull the meter if the base may be broken. We plan to get a new panel and most likely rob parts to replace any damaged components. The utility will re-energize the service without a permit so long as we don't replace the enclosure. We are concerned that we may find damage or corrosion which mandates replacing the panel, which will likely trigger a permit and inspection requirement. We want to be prepared lest the bar loses needed revenue.

I seriously doubt our local jurisdiction has a clue what they are doing, but I have seen the case in other jurisdictions where all the 120 VAC 15 AMP receptacles had to be two wire and fed with an upstream GFCI receptacle. We do not want any part of rewiring the building. My thought is to replace the two main disconnect circuit breakers with GFCI circuit breakers, but I'm unfamiliar and don't quite understand how a two pole GFCI breaker works.

The 200 AMP single phase meter panel feeds a 125 AMP four space CH4R load center with twin 60 AMP two pole CH260 miniature circuit breakers. The load center is the tan toggle plug on Cutler Hammer series. Downstream of each breaker there are only three conductors, L1, L2 and neutral (no ground). The CHGF breakers I see have two load lugs and a white pig tail. I also see Square D QO GFCI two pole breakers figured similarly.

As I said I don't understand how two pole GFCI circuit breaker function. Does anyone know if either or both of these breakers will feed both 120 and 240 loads simultaneously without tripping the GFCI? I would have thought you need a circuit breaker with neutral line and load connections.

 

[electrofelon]

You lost me at how you got from replacing a damaged meter socket to adding GFCI protection?

 

[dpwell]

I am concerned that if the jurisdiction notices there are no ground wires with the two runs from the service entrance load center, they may investigate further and require that existing personal use receptacles (and possibly other loads) either be provided grounds or GFCI protected.

Attached are pictures of the electric service. I imagine it was installed at least 40 years ago. It is not the original as the structure is several decades older.

 

[dpwell]

I think we got it. We mostly use QO & Homeline equipment. I'd rather replace the load center than chase after special CH circuit breakers.

Square D tech support specified the proper breaker to use. As I mentioned, I didn't see how the device could work without a load neutral and that is in fact the case. The QO260GFI is not designed to function with unbalanced 120 VAC loads. It is primarily only for 240 VAC loads. The QO260GFI3W has a neutral load lug and is designed for dual voltage loads. This information does not seem to be apparent in their catalog, but is mentioned in their online FAQs and some product literature. Attached is the instruction sheet.

 

[Little Bill]

You can use a 2-pole GFCI that has a neutral lug for loads with no neutral. The GFCI senses if there is a difference in current between the two legs. You don't have to have a neutral for it to work.

 

[jjconst]

You can use a 2-pole GFCI that has a neutral lug for loads with no neutral. The GFCI senses if there is a difference in current between the two legs. You don't have to have a neutral for it to work.

Thank you. that was a question I was having as im on my first new build and first time with the A/C needing to be GFCI.