Service Conductors to a Separate Building

[Little Bill]

I think I know the answer to my question but for some reason I'm not 100% certain, must be a "senior moment".:happysad:

Had a guy call about some work and part of it involved running power to a separate building. I haven't gone to look yet so I'm just going on what he told me.
He says he has a 400A service to a building and is only supplying a 200A panel to that building. He says the meter is a dual lug but I don't know if it's a 320A or true 400A. I also don't know if it's a commercial/industrial building or residential.
Anyway, he wants to power another 200A panel in a separate building from the other set of lugs in the meter base.

Question is, can the other building be supplied from the meter without a disconnect, and does it matter whether it's residential or commercial/industrial? Also, does it matter as far as whether the meter base is 320 or 400A?

Thanks!

 

[cadpoint]

Ask to see a year worth of power bills on his service!
or
You'll need to know all the numbers of the existing equipment that's on the existing service.

I'll state that you will need a means of disconnect because the new panel will probably be of some distance and out of sight of the main.

I'm not a fan of dual lugs or pass through lugs on panels or meters unless it's engineered,
it'll all be on you if you except the mission. Beside it'll probably be 320 rated service and the headaches will start... JMO...

 

[Dennis Alwon]

You will not need a disconnect at the first building if the meter has dual lugs. A main disconnect or the six handle rule will apply at the second building along with grounding electrodes etc.

 

[iwire]

I don't know if it's a 320A or true 400A.

A 320 is a 400.

Two - 200 amp panels are rated 320 amps continuous, 400 amp non continuous just like a 320 meter.

Question is, can the other building be supplied from the meter without a disconnect, and does it matter whether it's residential or commercial/industrial?

Yes, yes.

IV. Service-Entrance Conductors
230.40 Number of Service-Entrance Conductor Sets.
Each service drop or lateral shall supply only one set of
service-entrance conductors.

Exception No. 3: A single-family dwelling unit and a separate
structure shall be permitted to have one set of serviceentrance
conductors run to each from a single service drop
or lateral.

 

[Little Bill]

Ask to see a year worth of power bills on his service!
or
You'll need to know all the numbers of the existing equipment that's on the existing service.

I'll state that you will need a means of disconnect because the new panel will probably be of some distance and out of sight of the main.

I'm not a fan of dual lugs or pass through lugs on panels or meters unless it's engineered,
it'll all be on you if you except the mission. Beside it'll probably be 320 rated service and the headaches will start... JMO...

That's just it, there is no main. The current setup, as I understood the guy, is the meter is currently only serving a 200A panel in the building where the meter is at. He's not asking to feed from the current panel but have another set of service conductors run from the other set of lugs in the meter.
Seems I've read some posts here akin to this, such as 400A at house serving a 200A panel there, then serving a detached garage from the same meter without having to have a disconnect.

 

[cadpoint]

Does the TVA write there own version of the Code? I looked for their white book

Go to this web site and call the correct local AHJ, this map is almost the same as the Area covered by the TVA. How silly it's from the TVA site...

 

[Gac66610]

would (or could) 240.21(B)(5) apply?

I have a similar set up, coming up, this article was what I was looking at

 

[Little Bill]

A 320 is a 400.

Two - 200 amp panels are rated 320 amps continuous, 400 amp non continuous just like a 320 meter.






Yes, yes.

That's the section I was looking for! I was stuck on number of services and didn't make it to the "service-entrance conductors" part.

Thanks Iwire-U-wire-We all Wire!:lol:

And you too Dennis!:thumbsup:

 

[Little Bill]

A 320 is a 400.

Two - 200 amp panels are rated 320 amps continuous, 400 amp non continuous just like a 320 meter.

Forgot to mention this in my other post. I know a 320A meter is a 400A continuous meter. What I meant was isn't there also a true or non-continuous 400A meter? If so, can it feed two sets of SE conductors to two 200A panels providing the exception is met?

 

[Little Bill]

So if this is not a residential setting, what would be the best way to do this? Would you either have to add 2 disconnects outside, one for the first building and one for the second, both grouped at the meter? Or maybe use the tap rule and land the second set of conductors on a disconnect with OCPD?

 

[iwire]

Forgot to mention this in my other post. I know a 320A meter is a 400A continuous meter. What I meant was isn't there also a true or non-continuous 400A meter? If so, can it feed two sets of SE conductors to two 200A panels providing the exception is met?

You can use any 320 meter to supply two run of the mill 200 amp panels.

A typical 200 amp breaker is actually rated 200 amps non continuous or 160 amps continuous so the two combined are actually rated 320 amps continuous just like a 320 meter.