Who makes a good multi metering for 2 - 400 amp 3PH 120/208V CT services?

nicknorth

Senior Member
I was wanting to know what other people are using for multi metering that offer two CT metering for 400 amp 120/208 services?
 

nicknorth

Senior Member
I personally do not understand what you are asking. Are you talking about sub metering or utility metering?
After reading what I posted it is not the clearest thing in the world. What I meant to ask is what you all are using for multi-metering for a building that will have (2) 400amp 120/208 services with an overhead strike? Our POCO requires anything above 200amps to be CT metered. Our suppliers did not get back to us about if Siemens or GE had something that was already put together like their line of Power-Mod vs. installing 2 - CT's can, 2 - CT meter bases, 2 - 400 amp disconnects, 2 - overhead feeders with strikes, and 2 of everything else we need. I know Siemens would have something in their switchboard gear and that is what I'm familiar with using, but I know that is going to be way over the budget.

This job is a single building with two tenants. One tenant (dry cleaners) is existing that currently has a 400amp 120/240 Delta Service CT service with an overhead strike. The other tenant is new (restaurant) and requires a 400 amp 3 phase service and currently only has a single phase 200 amp service. Both services are in different locations with a overhead drop to each service which the POCO doesn't allow anymore so these have to be brought to together for one strike. The POCO will only provide 600amps if the building stays with the 120/240 Delta, but if we change it to 120/208Y system the POCO will allow up to 1,200 amps to this building so this is why we have to change out the service. The POCO doesn't know the fault current because they don't know what pole they will set the transformers on, but if we guessed that they would set these on the closest pole to the site the fault current could be no more then 30,000 amps. If they set the transformers on the next pole down then the fault is under 10k. The existing tenant that already has a 400amp service we will need to have a disconnect at the service because their panel has no main and we will use the CT can as our j-box.

I hope this makes sense now and someone can chime in and tell us what they are using and even post some pictures.
 

nicknorth

Senior Member
Siemens always does good.
So does SqD.
Our suppliers do Siemens and GE so we don't do much of any Sq D or Eaton. Do you have any pictures of any good services with 2 or more 400amp services? I see a lot of people out here doing 200amp services with 2 services to make a 400amp service which I guess if it was a new building or something like that its probably a more cost efficient way of doing things, but when you need a true 400 amp service this doesn't work.
 

kwired

Electron manager
Location
NE Nebraska
I see a lot of people out here doing 200amp services with 2 services to make a 400amp service which I guess if it was a new building or something like that its probably a more cost efficient way of doing things, but when you need a true 400 amp service this doesn't work.
Part of confusion here is that in those situations you generally don't have 2 services, technically you have one service with the up to six permitted disconnecting means. In general a building can only be supplied with one service, with some exceptions being different voltage, phase, frequency or other characteristics, and sometimes just because the capacity is larger than the utility will serve with a single service, but that is often over 2000 amps, maybe lower with single phase installations. Another problem that you have mentioned is what the POCO will supply you with as compared to what NEC will allow. Your situation of two different occupancies generally is acceptable to have separate service to each according to NEC, but apparently your POCO doesn't want to allow this.

The other thing you have is with multiple service disconnecting means, common supply conductors to both only need an ampacity equal or greater than the calculated load. What this means is even though you have 2- 400 amp overcurrent devices, if the total load calculation is only 525 amps, your common service conductors need not have an ampacity over 525 amps, but if you were to supply a single 800 amp device you would need 700 amps of conductors. (700 because of next higher standard overcurrent device rule, over 800 amps and this rule can not apply)
 

nicknorth

Senior Member
Part of confusion here is that in those situations you generally don't have 2 services, technically you have one service with the up to six permitted disconnecting means. In general a building can only be supplied with one service, with some exceptions being different voltage, phase, frequency or other characteristics, and sometimes just because the capacity is larger than the utility will serve with a single service, but that is often over 2000 amps, maybe lower with single phase installations. Another problem that you have mentioned is what the POCO will supply you with as compared to what NEC will allow. Your situation of two different occupancies generally is acceptable to have separate service to each according to NEC, but apparently your POCO doesn't want to allow this.

The other thing you have is with multiple service disconnecting means, common supply conductors to both only need an ampacity equal or greater than the calculated load. What this means is even though you have 2- 400 amp overcurrent devices, if the total load calculation is only 525 amps, your common service conductors need not have an ampacity over 525 amps, but if you were to supply a single 800 amp device you would need 700 amps of conductors. (700 because of next higher standard overcurrent device rule, over 800 amps and this rule can not apply)
Yes that is why I want to try and find a multi metering setup for this situation so I'm not installing and running a bunch of extra wiring and provide a nice clean look. Yes this is not normal to have to a building supplied with two overhead strikes in our area and I'm not even sure how this happened as this building is under 4,000 sq ft so these two services drops are within 30' of each other.
 

Sierrasparky

Senior Member
Location
USA
Occupation
Electrician ,contractor
Why not just to standing sections with a common pull section in the middle. That would be off the shelf.
 
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