Question on using aluminum conductor romex for a sub panel feeder in a residence???

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jango

jango

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My electrician suggested using an aluminum conductor romex to feed a sub panel in a standard residence (240V single phase). The sub panel will be a 200A rated panel and the breaker for the romex is a 200A circuit breaker. The distance is approx. 110' long. Is there a romex with aluminum conductors available in an adequate size/gauge for this application??? Any input would be greatly appreciated. Thanks
 
You need to use another wiring method. Either MC cable or SE cable would work.

III. Construction Specifications

334.104 Conductors. The 600-volt insulated conductors
shall be sizes 14 AWG through 2 AWG copper conductors
or sizes 12 AWG through 2 AWG aluminum or copper-clad
aluminum conductors. The communications conductors
shall comply with Part V of Article 800
Click to expand...
 
I just did a little research. It looks like the following will be acceptable:

AL 4/0 SER 200 A Aluminum 4/0-4/0-4/0-2/0 Service feeder wire for 200A breaker panel

Any input on this?
 
Yea may not work depending on the code version you are working under.
Used to do it but not now, in my area unless you use a lower breaker say 175amps.
Many don't even realize.
You can use a lower breaker to comply.
 
Based on 2008 and assuming the subpanel will supply ALL of the loads, 310.15(b)(6) allows a 4/0 aluminum for a 200Amp feeder.

Am i missing something?
 
You might be missing something. Is it a sub-panel or the main panel but located away from the meter? I believe for a sub-panel it's 310.16 and 4/0 Alum is 180a at 75 degrees. This came up a while ago with using #2 SER for a 100a sub-panel. It is only rated 90a.
 
Sierrasparky said:
Yea may not work depending on the code version you are working under.
Used to do it but not now, in my area unless you use a lower breaker say 175amps.
Many don't even realize.
You can use a lower breaker to comply.
Click to expand...

Opps using the 60 degree table that's only 150 amps,,,,
 
GerryB said:
You might be missing something. Is it a sub-panel or the main panel but located away from the meter? I believe for a sub-panel it's 310.16 and 4/0 Alum is 180a at 75 degrees. This came up a while ago with using #2 SER for a 100a sub-panel. It is only rated 90a.
Click to expand...

FYI, under the 2008 SER is now under the 60C column and under the 2011 it was moved back to 75C unless it is ran in insulation-then it 60C also.
 
jumper said:
FYI, under the 2008 SER is now under the 60C column and under the 2011 it was moved back to 75C unless it is ran in insulation-then it 60C also.
Click to expand...

Did not realize the difference in temp from the code cycles. This really makes a debacle. It's ok yesterday but not next week. Wait a few years and it will be ok.

It's the same darn wire. Either it's ok to load it up or not. What is the reasoning. I do electrical in a fairly cold climate I should be able to use the stuff in the wall even with insulation as its cooooold.
 
Sierrasparky said:
Did not realize the difference in temp from the code cycles. This really makes a debacle. It's ok yesterday but not next week. Wait a few years and it will be ok.

It's the same darn wire. Either it's ok to load it up or not. What is the reasoning. I do electrical in a fairly cold climate I should be able to use the stuff in the wall even with insulation as its cooooold.
Click to expand...

:thumbsup: Such is the NEC.
 
Sierrasparky said:
Boy that's a good excuse. No responsibility!:happysad:
Click to expand...

I don't get your post. Do you really think you have input to the NEC? I know a few members on this site have made recommendations, perhaps a few of those even make it into the code.

But let's be real: How many contractors thought AFCI's should be instituted? How many home's have caught fire because 4/0 SER was connected to a 200amp sub-panel? etc, etc, etc.
 
The point is how can the wire be good for a purpose today then bad tommorrow. Then a good for a particular tem then be bad later.
Either the NEC does their due diligence or not. This electrical thing we a do is not new. There are case histories. There are competent performance tests that can be done to verify the situation.
What whe know is that the NEC does not have competent performance test done and plays to the lobbyists.
 
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