resi 400 amp service

[danger30]

I've got a customer that wants to use a 400 amp meter main (with two 200A main breakers) to feed two panels in his new home. The meter will be mounted on the house with the panels directly behind it. I had figured a 400A meter base in my bid, but he now wants to supply the meter.(got a heck of a deal at home depot) Wouldn't 225.30 prohibit the use of two mains feeding your house panels? I don't think it's right, but now that I'm thinking of it, what would be the problem with having two sets of fused conductors versus non-fused?

 

[ceb58]

I've got a customer that wants to use a 400 amp meter main (with two 200A main breakers) to feed two panels in his new home. The meter will be mounted on the house with the panels directly behind it. I had figured a 400A meter base in my bid, but he now wants to supply the meter.(got a heck of a deal at home depot) Wouldn't 225.30 prohibit the use of two mains feeding your house panels? I don't think it's right, but now that I'm thinking of it, what would be the problem with having two sets of fused conductors versus non-fused?

No problem, done all the time. But the only reason to use the meter combo would be if the panels were to be located elsewhere violating the closest point of entry rule. Your only problem now is you will need 250mcm Al SER (4) wire to feed the panels (if under 2008) or 3/0 Cu. The panels inside are now sub panels. His heck of a deal may go out the window now that the wire type has changed.

 

[danger30]

I don't do much residential, but doesn't 225.30 prohibit the house from being fed from two feeders, or am I over thinking this?

 

[jwjrw]

I don't do much residential, but doesn't 225.30 prohibit the house from being fed from two feeders, or am I over thinking this?

Your overthinking it. You are just running 2 subpanels..

 

[augie47]

You are probably overthinking :grin: The HOUSE is fed by one service.
Once the house is supplied, there is not a limit on feeders in the same building.

 

[Sierrasparky]

I don't see the problem. The home is not fed by two laterals. You are just feeding two sub panels from the one Meter/main correct?

 

[danger30]

225.30 Number of Supplies
"Where more than one building or structure is on the same property and under single management, each additional building or structure that is served by a branch circuit or feeder on the load side of the service disconnecting means shall be supplied by one feeder or branch circuit"
I have used 400A meter-mains to feed both the house and a shop/detached garage, but never for two 200A house panels.

 

[danger30]

I guess I should have mentioned there is a detached shop with it's own service.:grin:

 

[jwjrw]

225.30 Number of Supplies
"Where more than one building or structure is on the same property and under single management, each additional building or structure that is served by a branch circuit or feeder on the load side of the service disconnecting means shall be supplied by one feeder or branch circuit"
I have used 400A meter-mains to feed both the house and a shop/detached garage, but never for two 200A house panels.

But your feeding the structure not an additional building right?

 

[danger30]

Yes I'm "feeding" it on the load side of the service disconnecting means with more than one feeder.

 

[jwjrw]

Yes I'm "feeding" it on the load side of the service disconnecting means with more than one feeder.

If only the NEC made it easy... You may do this and this but not that....

 

[curt swartz]

What do you mean you are feeding it on the load side? You are bringing 2 feeders to the dwelling and connecting the panel in the house to the line side of the meter?

 

[danger30]

There are two service disconnects on the exterior of the house. From each of the disconnects are two feeders supplying two separate 200A Main panels in the house.

 

[infinity]

Since your meter/main is mounted on the house the sub-panels can be installed anywhere you want within the house. As Ceb58 stated the use of larger conductors will now be required for the sub-panels. All of your required bonding and grounding will take place at the meter/main.

 

[danger30]

Sure you can have multiple sub-panels in one structure but they are all usually fed from one service or source aren't they? I guess I'm stubborn, I should probably be doing something a little more productive than arguing with you guys.:grin:

 

[infinity]

Sure you can have multiple sub-panels in one structure but they are all usually fed from one service or source aren't they? I guess I'm stubborn, I should probably be doing something a little more productive than arguing with you guys.:grin:

There is no limit on the number of sub-panels that you can have or where they're fed from. Are you thinking of a code Article that would provide such a prohibition?

 

[jwjrw]

Sure you can have multiple sub-panels in one structure but they are all usually fed from one service or source aren't they? I guess I'm stubborn, I should probably be doing something a little more productive than arguing with you guys.:grin:

Both of the 200a panels will be supplied from the same source

 

[danger30]

So....the fact that the service is mounted on the house, and not on another structure makes this OK? I can probably digest that.

 

[ceb58]

So....the fact that the service is mounted on the house, and not on another structure makes this OK? I can probably digest that.

Now your getting it The service is on the building. You are feeding the sub panels in that building. You are not feeding another building. Now take some aspirin and lie down for a while

 

[KWH]

Why does this application require a SER cable larger than 4/0AL installed to each individual sub panel