Service from utility terminated in enclosure with 2 mains. One main would feed 6 meters and the other main would feed one meter...Is this allowed?

[Volt-Amps]

Please see image
Is this feasible...or allowed? Any issues you can think of with this approach?

 

[electrofelon]

Starting in the 2020 code, service disconnects must be in separate enclosures. What code are you on?

 

[electrofelon]

2020 Code Language:

230.71(B) Two to Six Service Disconnecting Means. Two to six service disconnects shall be permitted for each service permitted by 230.2 or for each set of service-entrance conductors permitted by 230.40, Exception No. 1, 3, 4, or 5. The two to six service disconnecting means shall be permitted to consist of a combination of any of the following:

(1) Separate enclosures with a main service disconnecting means in each enclosure

(2) Panelboards with a main service disconnecting means in each panelboard enclosure

(3) Switchboard(s) where there is only one service disconnect in each separate vertical section where there are barriers separating each vertical section

(4) Service disconnects in switchgear or metering centers where each disconnect is located in a separate compartment

 

[Volt-Amps]

Starting in the 2020 code, service disconnects must be in separate enclosures. What code are you on?

Chicago Electrical Code

 

[electrofelon]

Chicago Electrical Code

Does that have something similar to 230.71(B)?

 

[Volt-Amps]

2020 Code Language:

230.71(B) Two to Six Service Disconnecting Means. Two to six service disconnects shall be permitted for each service permitted by 230.2 or for each set of service-entrance conductors permitted by 230.40, Exception No. 1, 3, 4, or 5. The two to six service disconnecting means shall be permitted to consist of a combination of any of the following:

(1) Separate enclosures with a main service disconnecting means in each enclosure

(2) Panelboards with a main service disconnecting means in each panelboard enclosure

(3) Switchboard(s) where there is only one service disconnect in each separate vertical section where there are barriers separating each vertical section

(4) Service disconnects in switchgear or metering centers where each disconnect is located in a separate compartment

Can we keep the existing meter bank and its 400A main as is, but add a wireway ahead of it, terminate the new 600A service conductors in the wireway and from their provide 2 taps (one goes to the existing 400A main and one to a new 200A panel)? a max 10-ft tap.

 

[electrofelon]

Can we keep the existing meter bank and its 400A main as is, but add a wireway ahead of it, terminate the new 600A service conductors in the wireway and from their provide 2 taps (one goes to the existing 400A main and one to a new 200A panel)? a max 10-ft tap.

Sure, that would be a 230.40 exception #2 install, done all the time. Just keep 230.70(A)(1) in mind.

 

[Volt-Amps]

Does that have something similar to 230.71(B)?

 

[Volt-Amps]

See section A, line 6. Chicago electrical code allows single enclosure. Do you agree?

 

[electrofelon]

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That appears to be the same as the 2017 code which allowed multiple service disconnects in a single enclosure. I have zero familiarity with the Chicago electrical code, don't know if it's just the NEC or has differences or amendments, or if they require the separate enclosure thing but it's in a different section. Maybe someone more familiar with your jurisdiction can give you better confirmation than I can.

 

[jaggedben]

Broadly speaking the answer to the original question ought to be yes, in theory. Aside from the enclosure issue mentioned so far, you'll probably also need to do a load calculation to show that the calculated load does not exceed the existing service conductor rating (which I presume to be 400A).

 

[Elect117]

NEC 2020----

230.40 Exception 2 applies. So that is in your favor.

If you group the disconnects you should be fine. You shouldn't tap the 800A section, but rather get one that has landings for paddles. Installing supply side taps isn't always easy.

230.90(A) - Also remember that you can't round up with taps. So if you tap to refeed the 400A section you need more than 400A of conductor and the same for the 200A OCPD.

1/3 of 800 is 240A. If you are worried about not meeting the 10' tap rule (which is hard to do) then install more than 240A of conductor and a 200A main OCPD.

Your issues appears to be space. You will have to fit it all in there so that the doors open, dedicated spaces are met, and working spaces are clear. You might also need panic hardware on the door if it meets that requirement.

Side notes:
110.26(E)(1) - water lines or gas lines in the dedicated space above the meter center.

And don't forget the receptacle for servicing.

 

[Volt-Amps]

NEC 2020----

230.40 Exception 2 applies. So that is in your favor.

If you group the disconnects you should be fine. You shouldn't tap the 800A section, but rather get one that has landings for paddles. Installing supply side taps isn't always easy.

230.90(A) - Also remember that you can't round up with taps. So if you tap to refeed the 400A section you need more than 400A of conductor and the same for the 200A OCPD.

1/3 of 800 is 240A. If you are worried about not meeting the 10' tap rule (which is hard to do) then install more than 240A of conductor and a 200A main OCPD.

Your issues appears to be space. You will have to fit it all in there so that the doors open, dedicated spaces are met, and working spaces are clear. You might also need panic hardware on the door if it meets that requirement.

Side notes:
110.26(E)(1) - water lines or gas lines in the dedicated space above the meter center.

And don't forget the receptacle for servicing.

We only need 600A, do I need to go with 800A section per your reply above?

 

[electrofelon]

NEC 2020----

230.40 Exception 2 applies. So that is in your favor.

If you group the disconnects you should be fine. You shouldn't tap the 800A section, but rather get one that has landings for paddles. Installing supply side taps isn't always easy.

230.90(A) - Also remember that you can't round up with taps. So if you tap to refeed the 400A section you need more than 400A of conductor and the same for the 200A OCPD.

1/3 of 800 is 240A. If you are worried about not meeting the 10' tap rule (which is hard to do) then install more than 240A of conductor and a 200A main OCPD.

Your issues appears to be space. You will have to fit it all in there so that the doors open, dedicated spaces are met, and working spaces are clear. You might also need panic hardware on the door if it meets that requirement.

Side notes:
110.26(E)(1) - water lines or gas lines in the dedicated space above the meter center.

And don't forget the receptacle for servicing.

Note these are service conductors, so the article 240 tap rules do not apply. You can still use next size up if under 800A.

 

[electrofelon]

We only need 600A, do I need to go with 800A section per your reply above?

Service conductors that feed multiple service disconnects are permitted to be sized to the load.

 

[Elect117]

I guess exception 2 is an option in 230.90(A). I missed that. The next size up works. Sorry for the confusion.

Electrofelon is right. I was wrong to include tap rules. You can use a 800A section or 600A section and it wouldn't change the conductor sizing or service OCPD.

 

[david]

Can we keep the existing meter bank and its 400A main as is, but add a wireway ahead of it, terminate the new 600A service conductors in the wireway and from their provide 2 taps (one goes to the existing 400A main and one to a new 200A panel)? a max 10-ft tap.

Why are you scraping the existing 400 amp service entrance cables.

Why not just install a second set of 200 or 300 amp service entrance conductors.

I'm not understanding why you want to install 600 amp service entrance just to tap it and separate into 400 amp existing and another tap to 200 amp new
If that's what you want to do, perfectly fine, just not understanding why do it that way

 

[electrofelon]

Why are you scraping the existing 400 amp service entrance cables.

Why not just install a second set of 200 or 300 amp service entrance conductors.

I'm not understanding why you want to install 600 amp service entrance just to tap it and separate into 400 amp existing and another tap to 200 amp new
If that's what you want to do, perfectly fine, just not understanding why do it that way

That a good point. I would leave the 400 just as is, and add another independent 200A set to another service disconnect using 230.40 exception #2. Certainly could have a parallel set of 600's, and tap it but seems like more work and connectors.

 

[Volt-Amps]

Why are you scraping the existing 400 amp service entrance cables.

Why not just install a second set of 200 or 300 amp service entrance conductors.

I'm not understanding why you want to install 600 amp service entrance just to tap it and separate into 400 amp existing and another tap to 200 amp new
If that's what you want to do, perfectly fine, just not understanding why do it that way

I may have miscommunicated what I want to do, but thee intent is to upsize the existing feeders to 600A from 400A. Adding another set of 3/0 should do, depending on how many lugs or landings we have, which I suppose should be OK.

 

[kwired]

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This is basically same thing that NEC prior to 2020 had. If that is what your adopted code is then you can have all six permitted mains in same enclosure.