3 -300 MCM's in 2 1/2" PVC ??

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SCH. 40 pvc thhn cu wire

I am feeding two 150 amp panels for two apartments that have been converted in to one apartment.
The 300 mcm will be going from the top of the 320 single meter base up to the gutter. Then below, when it leaves the meter it will go to two 150 amp main breaker panels.
I have sized the wire because of two 150 amp breakers. But really the load is less then 200 amps. It only has one stove and one furnace.
Should I base this wire size on the load instead of the two 150 amp breakers.

I am useing the 320 meter because the lugs, and feeding two panels.
From the one meter base.
I have 12 of these aptments to do.
 
buckofdurham said:
SCH. 40 pvc thhn cu wire

I am feeding two 150 amp panels for two apartments that have been converted in to one apartment.
The 300 mcm will be going from the top of the 320 single meter base up to the gutter. Then below, when it leaves the meter it will go to two 150 amp main breaker panels.
I have sized the wire because of two 150 amp breakers. But really the load is less then 200 amps. It only has one stove and one furnace.
Should I base this wire size on the load instead of the two 150 amp breakers.

I am useing the 320 meter because the lugs, and feeding two panels.
From the one meter base.
I have 12 of these aptments to do.
Click to expand...


Yes, This is the smarter move. Up size the wire one size if you are worried about it. You would be able to use 1 1/2" conduit for a 200amp feed.
 
acrwc10 said:
Yes, This is the smarter move. Up size the wire one size if you are worried about it. You would be able to use 1 1/2" conduit for a 200amp feed.
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Oh good, Thanks, May be I'll go to 3/0 copper

Seems like so many people when coming out of the meter they always size the wire to the breaker.
I guess that is for a single meter feeding a single main breaker
 
raider1 said:
I agree with Larry, the LB could very well be your limiting factor.

Chris
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I also agree with Larry&Chris-the LB more than likely will not work for this application,maybe you can use a piece of troff-,to act as an LB-We have done this many times with good results...
 
buckofdurham said:
Oh good, Thanks, May be I'll go to 3/0 copper

Seems like so many people when coming out of the meter they always size the wire to the breaker.
I guess that is for a single meter feeding a single main breaker
Click to expand...

Hold on! IMO NEC 230.42(B) may require that the conductors between the meter and the two 150A breakers be rated for 300A.
 
jflynn said:
I also agree with Larry&Chris-the LB more than likely will not work for this application,maybe you can use a piece of troff-,to act as an LB-We have done this many times with good results...
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If i figured correctly. you'll need an LB that is 18" long ( mogul ) using the 3" conduit. If you use a wireway. it'll need to be 5" x5" x 21" custom or a 6" x 6" x 24" standard.
Rick
 
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chris kennedy said:
Not a fan of big wire in LB's. This is four 500's and a #3 in 4" conduit. I believe a 4" LB is good for three 600's. Why struggle if you don't have to?
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Not to mention that a piece of wireway may end up costing less, especially if you are dealing with a malleable LB.
 
Sometimes its just easier to use a w/p lb outdoors than deal with weather proofing a wireway.Hey chris why the w/p fixture?
 
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