I have just finished wiring a large house and have used two 200A panels. I was told that the way to build the service is to use a 320A meter can and run two 4/0 al ser directly to the main breakers of the panels as long as they are within 9 feet of the can. I cannot find this in the codebook. Is this OK
Residential service disconnect?
- Thread starter veep
- Start date
- Status
- Location
- Bremerton, Washington
- Occupation
- Master Electrician
Re: Residential service disconnect?
Its not in the NEC, the meter is not required by the NEC. The meter is installed per the utilities requirements, thats where you need to start to see if you can use a class 320 meter. The 9 feet is not an nec issue either, it may be a local code. In washington state the distance for unfused service entrance conductors is 15 feet by state code.
Its not in the NEC, the meter is not required by the NEC. The meter is installed per the utilities requirements, thats where you need to start to see if you can use a class 320 meter. The 9 feet is not an nec issue either, it may be a local code. In washington state the distance for unfused service entrance conductors is 15 feet by state code.
tonto gonzales
Member
Re: Residential service disconnect?
We install 2 200 amp panels in most of the new homes we wire. The use of a 320 amp meter base is common for residential applications.
We install 2 200 amp panels in most of the new homes we wire. The use of a 320 amp meter base is common for residential applications.
ty
Senior Member
- Location
- 3rd Rock from the Sun
Re: Residential service disconnect?
The 320amp can typically uses the same plug-in meter as a 200amp can. The 400amp can typically uses a bolt-in meter.
I say typically because I don't know all specs for all cans for all utility companies.
We use the 400amp can, even when the utility allows the use of the 320amp can.
There are pros and cons for each.
The 320amp can is smaller, lighter, and less expensive, but the 400amp can definately has more room to work in. Especially bending radius into lugs.
The 320amp can typically uses the same plug-in meter as a 200amp can. The 400amp can typically uses a bolt-in meter.
I say typically because I don't know all specs for all cans for all utility companies.
We use the 400amp can, even when the utility allows the use of the 320amp can.
There are pros and cons for each.
The 320amp can is smaller, lighter, and less expensive, but the 400amp can definately has more room to work in. Especially bending radius into lugs.
ty
Senior Member
- Location
- 3rd Rock from the Sun
Re: Residential service disconnect?
One utility that we work with just recently started allowing the 320amp can. Anything over that and you have to use a C.T. cabinet.
One utility that we work with just recently started allowing the 320amp can. Anything over that and you have to use a C.T. cabinet.
ty
Senior Member
- Location
- 3rd Rock from the Sun
Re: Residential service disconnect?
It's quite common to buid a '400 amp' service and get '100 amp' C.T.'s from the utility company.
Re: Residential service disconnect?
Ty I have used a 320amp meter base, residential, but installed only a 200amp MB and 100amp MB panel, am I missing something here, what Veep is describing to me is a need for a 400amp ct can.
Ty I have used a 320amp meter base, residential, but installed only a 200amp MB and 100amp MB panel, am I missing something here, what Veep is describing to me is a need for a 400amp ct can.
I too have used 2 200amp MB panels in a residential setting, single family, but I have used a 400amp ct can, and a lot of the homes we have wired are using a 320amp service, but with the set up I described, 1 200amp MB panel and 1 100ampMB panel.
ty
Senior Member
- Location
- 3rd Rock from the Sun
Re: Residential service disconnect?
jro, I agree with you, that's one reason we use the 400amp can or C.T. cabinet where required. But, some utilities will allow the use of the 320amp can with (2) 200amp panels. As Tom stated, it's not a Code requirement. And that's why, even with (2) 200amp panels, it's quite common for one of the utilities that we deal with to give 100amp C.T.'s, not 200 or even 400.
One utility prefers the 320can (even if you have (2) 200amp panels) because their meter crew only has to carry one type of meter, the plug-in type.
jro, I agree with you, that's one reason we use the 400amp can or C.T. cabinet where required. But, some utilities will allow the use of the 320amp can with (2) 200amp panels. As Tom stated, it's not a Code requirement. And that's why, even with (2) 200amp panels, it's quite common for one of the utilities that we deal with to give 100amp C.T.'s, not 200 or even 400.
One utility prefers the 320can (even if you have (2) 200amp panels) because their meter crew only has to carry one type of meter, the plug-in type.
- Location
- Massachusetts
Re: Residential service disconnect?
Maybe you have some different products available in your locations, but around here I have never seen a 400 amp continuous meter socket.
What we get out here are 320 amp continuous 400 amp max meter sockets.
This perfect for two 200 amp panels, the total continuous load for two 200 amp panels should not exceed 320 amps.
You can go up to 400 amps for 180 minute's.
Maybe you have some different products available in your locations, but around here I have never seen a 400 amp continuous meter socket.
What we get out here are 320 amp continuous 400 amp max meter sockets.
This perfect for two 200 amp panels, the total continuous load for two 200 amp panels should not exceed 320 amps.
You can go up to 400 amps for 180 minute's.
Re: Residential service disconnect?
Well I do have to know what you don't understand first.
Let me ask so that we may get to the bottom of the problem.
Do you understand the definition of continuous load?
If so please state it in your next post.
Roger
Well I do have to know what you don't understand first.
Let me ask so that we may get to the bottom of the problem.
Do you understand the definition of continuous load?
If so please state it in your next post.
Roger
Re: Residential service disconnect?
Lets see if I can get this right, Continuous Load: a load where the maximum current is expected to continue for 3 hours or more. By the way roger I do hold a master electricians license and own an electrical contracting business, with 22 years experience in the electrical trade.
Lets see if I can get this right, Continuous Load: a load where the maximum current is expected to continue for 3 hours or more.
By the way roger I do hold a master electricians license and own an electrical contracting business, with 22 years experience in the electrical trade. - Status