Can 4/0 SER (3-4/0s with one 2/0) be substituted with 4/0, 4/0, 2/0, 2/0 ?

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Stevenfyeager said:
I noticed 4/0 SER (4/0 x 3, and one 2/0) doesn’t downsize the neutral, can I downsize the neutral when using single conductors in pvc? Thanks
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If the calculated neutral load per 220.61 is under the ampacity of the 2/0 Al (135A typically), sure.

My understanding is that SER was originally designed for 3 phase services, for which use it would have (3) 4/0 insulated ungrounded conductors, and (1) 2/0 bare neutral.

Cheers, Wayne
 
I have when transitioning from ser to thhn or xhhw in conduit done the thhn or xhhw sized to what was either cost effective like mobile home feeder cable or what I could size it down to and have never been corrected for it. So if it's not allowed like when under breakering romex having the ground under sized its never been called so if an inspector questioned it he couldn't find a code reference to say its a no go.
 
Thank you for your help. I don't do much commerc. work. I recently ran all mc in a warehouse/store, but the biggest I have run was MC 6-3.
Should I consider running a 4 wire 4/0 MC from one of the meter disconnect combos to about 80 feet to a sub panel ? I've never ran conduit that large. Would it be easier or cheaper than conduit ? I see 230.50 B (1) and (2) (2) mentions using MC, but 230.50 B (1) does not. Am I allowed to use MC because this is not a service entrance cable, but "other than service entrance" cables ? (to a sub panel ) I see 4/0 -3 with #2 G MC on line for $10/ ft
Thank you so much !
 
Stevenfyeager said:
Thank you for your help. I don't do much commerc. work. I recently ran all mc in a warehouse/store, but the biggest I have run was MC 6-3.
Should I consider running a 4 wire 4/0 MC from one of the meter disconnect combos to about 80 feet to a sub panel ? I've never ran conduit that large. Would it be easier or cheaper than conduit ? I see 230.50 B (1) and (2) (2) mentions using MC, but 230.50 B (1) does not. Am I allowed to use MC because this is not a service entrance cable, but "other than service entrance" cables ? (to a sub panel ) I see 4/0 -3 with #2 G MC on line for $10/ ft
Thank you so much !
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I use AL MC all the time for feeders in commercial applications. It's a big labor saver for sure. It is fine run exposed most of the time.
 
Stevenfyeager said:
I've only used 12-2 MC to 6-3 MC, how do you cut the jacket on 4/0 MC ? Is there a special cutting tool like for small MC ? Thank you
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Same as smaller MC: kink, untwist and cut with klein 1104's.....or, especially for larger sizes, you can slice the armor with a fine sawzall blade, untwist it and pull it off.

I like the Arlington 8412-8418 series of connectors.
 
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