350 kcmil aluminum

[Dennis Alwon]

You are thinking 2 conductors per phase, he is not.

Then how does 350mcm aluminum work on 300 amps.

 

[ceb58]

You are thinking 2 conductors per phase, he is not.

its to feed (2) 150 amp main breakers

OK, he said the above.
May be not enough info. given.
Dennis I was assuming se cable. And we know what happens when we ass u me.

 

[Dennis Alwon]

Dennis I was assuming se cable. And we know what happens when we ass u me.

If he used se as a service entrance then he can use it at 75C. No? 338.10(B)(4)

(4) Installation Methods for Branch Circuits and Feeders.
(a) Interior Installations. In addition to the provisions of this article, Type SE service-entrance cable used for interior wiring shall comply with the installation requirements of Part II of Article 334.
FPN: See 310.10 for temperature limitation of conductors.
(b) Exterior Installations. In addition to the provisions of this article, service-entrance cable used for feeders or branch circuits, where installed as exterior wiring, shall be installed in accordance with Part I of Article 225. The cable shall be supported in accordance with 334.30. Type USE cable installed as underground feeder and branch circuit cable shall comply with Part II of Article 340.

 

[All Amped Up]

ok here it is . the customer only requires a 200 amp service. he's got big plans. so he says. he insist on 320amp
so thats what he's getting. how about i do this 1.- over head service . pvc down to 320 A single phase meter. I'll get three wire cuts. 2.- install (2) 200 amp 3R disconnects on each side . (they must be outside in this situation) 3.- run 4/0 ser to (2) 200 amp main lug panels. Now, can I use 350 mcm aluminum as my service drop conductors. (1 wire per Phase) ?

 

[benaround]

ok here it is . the customer only requires a 200 amp service. he's got big plans. so he says. he insist on 320amp
so thats what he's getting. how about i do this 1.- over head service . pvc down to 320 A single phase meter. I'll get three wire cuts. 2.- install (2) 200 amp 3R disconnects on each side . (they must be outside in this situation) 3.- run 4/0 ser to (2) 200 amp main lug panels. Now, can I use 350 mcm aluminum as my service drop conductors. (1 wire per Phase) ?

Yes you can, as long as the insulation is in the list of 310.15(B)(6) and the (2) 200a 3R

disconnects are fusable or c.b.'s.

 

[Dennis Alwon]

Now, can I use 350 mcm aluminum as my service drop conductors. (1 wire per Phase) ?

As long as the service drop conductors are more than the calculated load you are good. The problem is if the customer wants a 320 amp service then you are only really supplying him with 250 amps since 350 kcm aluminum is only rated for 250 amps.

I never understand this 320 amp service-- it really doesn't exist in the real world. 300, 400 but not 320 amps. The 400 amp meter base is rated 320 amps continuous and 400 amps non-continuous. Your panels are rated 150 each so you have 300 amps there but your riser is only good for 250amps.

 

[benaround]

Dennis,

Table 310.15(B)(6) rates 350mcm Alum. for 300amps @ 120/240 vac 3 wire single phase.

I was wondering where the 300a was coming from in the OP, there it is.

 

[Dennis Alwon]

Dennis,

Table 310.15(B)(6) rates 350mcm Alum. for 300amps @ 120/240 vac 3 wire single phase.

I was wondering where the 300a was coming from in the OP, there it is.

Thanks-- I missed that.