Installing a Generator Ahead of Meters

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goldstar

goldstar

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New Jersey
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Electrical Contractor
A question was posed at my contractors' association meeting last night as to whether it would be acceptable to install an automatic standby generator and associated transfer switch ahead of a meter stack. This would be at a multi-family unit with an 800 amp service and (for arguments sake) let's say 6-8 meters. There would be a disconnect switch ahead of the meter stack. The question arose because if the generator was installed in this manner, once on emergency power came on line the meters would register power when not provided by the POCO (and rest assured the dwelling unit occupants would have a problem with that).

If anyone knows of an accurate answer or Code section/violation please post it here. Also, any opinions would be greatly appreciated. I wish I could provide more info but this was posed as a hypothetical question. I guessing the other alternative would be to have a transfer switch for each dwelling unit which is out of the question for a number of reasons.

Thanks in advance.
 
IF you did so, the Transfer Switch would need to be Service Rated... not inexpensive... and you would to address load shedding assuming the generator was not full load rated,
 
But you are right, the meters would then register the energy from the generators, so they would be paying double for that; paying the utility for power they didn’t actually provide, and paying for the fuel to run the generator.
 
I have thought about this and was in a situation where I almost considered doing it. It was the same situation where there were 6 meters and it is clearly much simpler to put one transfer switch ahead of the meters. I didnt really see the utility meters counting generator power as an issue as the generator usage would, presumably, be very infrequent and short, and in this case the building owner would provide the generator fuel. I have the feeling the POCO would not like it (even though they should).
 
as someone that has actually worked on POCO lines I wouldn’t care for it unless there was an additional disconnect that we have access to that will provide a visual opening.
after the meter we have the meter for a visual opening.

i have fried a generator that was connected to a mobile home with a homemade double male ended dropcord.
the fuse was out at the transformer, I knew the transformer was backfeeding, I could hear it.
I threw the fuse in and the magic smoke came out of the cheap generator...
what was funny the guy wanted us to pay for the generator.
that didn’t happen..
 
Jraef said:
But you are right, the meters would then register the energy from the generators, so they would be paying double for that; paying the utility for power they didn’t actually provide, and paying for the fuel to run the generator.
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Aside from any possible Code violations that is probably the main issue. If I were a resident in this situation, if the power went out for only a few hours - no big deal. However, if it went out for several days or a week - then I have a gripe.
 
goldstar said:
Aside from any possible Code violations that is probably the main issue. If I were a resident in this situation, if the power went out for only a few hours - no big deal. However, if it went out for several days or a week - then I have a gripe.
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But I dont see the residents paying for the generator fuel on this situation. Seems like it would be an owner supplied thing. I suppose fuel could be divided equally between the tenants.
 
goldstar said:
A question was posed at my contractors' association meeting last night as to whether it would be acceptable to install an automatic standby generator and associated transfer switch ahead of a meter stack. This would be at a multi-family unit with an 800 amp service and (for arguments sake) let's say 6-8 meters. There would be a disconnect switch ahead of the meter stack. The question arose because if the generator was installed in this manner, once on emergency power came on line the meters would register power when not provided by the POCO (and rest assured the dwelling unit occupants would have a problem with that).

If anyone knows of an accurate answer or Code section/violation please post it here. Also, any opinions would be greatly appreciated. I wish I could provide more info but this was posed as a hypothetical question. I guessing the other alternative would be to have a transfer switch for each dwelling unit which is out of the question for a number of reasons.

Thanks in advance.
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It seems to me that the correct (not the least expensive) way to do this would be to install a separate ATS behind every meter and wire them in parallel to the generator.
 
ggunn said:
It seems to me that the correct (not the least expensive) way to do this would be to install a separate ATS behind every meter and wire them in parallel to the generator.
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I would agree. I can't imagine any POCO allowing an ATS ahead of their revenue meter as it could have all kinds of legal/tariff implications.
 
electrofelon said:
As far as a specific thing the POCO wouldn't like, wouldn't this mean the generator's charger and block heater power would be unmetered?
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Don't those loads usually draw from a breaker in the MDP or subpanel? In this case if there isn't a house meter one of the tenants would have to pick up the tab. I guess they could monitor it and let the landlord reimburse the tenant.
 
ggunn said:
Don't those loads usually draw from a breaker in the MDP or subpanel? In this case if there isn't a house meter one of the tenants would have to pick up the tab. I guess they could monitor it and let the landlord reimburse the tenant.
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The concern was, I think, that the block heater, battery charger, etc. are often prewired on the generator to the utility power side of an associated transfer switch.
 
ggunn said:
Don't those loads usually draw from a breaker in the MDP or subpanel? In this case if there isn't a house meter one of the tenants would have to pick up the tab. I guess they could monitor it and let the landlord reimburse the tenant.
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i would think 210.25 would not allow this.
 
GoldDigger said:
The concern was, I think, that the block heater, battery charger, etc. are often prewired on the generator to the utility power side of an associated transfer switch.
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In that case it would still pull from one of the tenants' meters.
 
ggunn said:
In that case it would still pull from one of the tenants' meters.
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Again...
210.25 Branch Circuits in Buildings with More Than One Occupancy.
(A) Dwelling Unit Branch Circuits. Branch circuits in each dwelling unit shall supply only loads within that dwelling unit or loads associated only with that dwelling unit.
(B) Common Area Branch Circuits. Branch circuits installed for the purpose of lighting, central alarm, signal, communica‐ tions, or other purposes for public or common areas of a two- family dwelling, a multifamily dwelling, or a multi-occupancy building shall not be supplied from equipment that supplies an individual dwelling unit or tenant space.
 
Hv&Lv said:
Again...
210.25 Branch Circuits in Buildings with More Than One Occupancy.
(A) Dwelling Unit Branch Circuits. Branch circuits in each dwelling unit shall supply only loads within that dwelling unit or loads associated only with that dwelling unit.
(B) Common Area Branch Circuits. Branch circuits installed for the purpose of lighting, central alarm, signal, communica‐ tions, or other purposes for public or common areas of a two- family dwelling, a multifamily dwelling, or a multi-occupancy building shall not be supplied from equipment that supplies an individual dwelling unit or tenant space.
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How is that section interpreted? Can you run a home run from a multifamily basement panel to a 3rd floor unit up an outside wall or some other wall in a unit? Or is it that you cannot have a junction box in one unit with wires spliced through it to another unit.
 
GerryB said:
How is that section interpreted? Can you run a home run from a multifamily basement panel to a 3rd floor unit up an outside wall or some other wall in a unit? Or is it that you cannot have a junction box in one unit with wires spliced through it to another unit.
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I see it as doing away with the multi family basement panel altogether.
 
goldstar said:
A question was posed at my contractors' association meeting last night as to whether it would be acceptable to install an automatic standby generator and associated transfer switch ahead of a meter stack. This would be at a multi-family unit with an 800 amp service and (for arguments sake) let's say 6-8 meters. There would be a disconnect switch ahead of the meter stack. The question arose because if the generator was installed in this manner, once on emergency power came on line the meters would register power when not provided by the POCO (and rest assured the dwelling unit occupants would have a problem with that).
Click to expand...

You don't say whether the residents are renters or condo owners. If they are tenants, they don't care if the power comes from the POCO or the generator. The meter will read the power used and they will send in their money to the POCO as usual. If these are condo owners who will also own the generator and it's just a matter of paying the POCO for power they generated themselves, then here is the solution:

Calculate the cost of putting a separate ATS on the load side of each meter. It will be expensive. Calculate the cost of putting one ATS before the meters, it will be much less expensive. Subtract one from the other and get the savings for using one large ATS. Divide that by the KW rate and get how many KW's you have to use to break even. That number will probably be many years worth. Then hold a meeting and ask if they want to pay it all up front, or over that many years. After the vote, install the single large ATS they will vote for.

P.S. Have you checked with the POCO to see if they have a solution for you. This can't be the first time this has come up. Perhaps they will install a meter on the output side of the generator and repay the owners for the power generated during their blackout to compensate for their individual meters being turned.
 
electrofelon said:
But I dont see the residents paying for the generator fuel on this situation. Seems like it would be an owner supplied thing. I suppose fuel could be divided equally between the tenants.
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That's a good point. This was a simple question that was posed at the meeting and there wasn't a lot of additional information provided. I'm guessing that the landlord was providing the gen set and probably putting a surcharge on the rent.
 
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