Poco conductor

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hhsting

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Glen bunie, md, us
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Junior plan reviewer
I have plans that show utility poco conductors from utility xfmr 5 sets of 4#600 kcmil + 1#3/0G. Of course these are just plans but has Anyone ever seen POCO providing #3/0G equipment grounding conductor?
 
kwired said:
Maybe it is two phase five wire :)
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It’s three phase 480/277V. I didn’t think there would be any need for EGC. Engineer who is designing it says no need for main bonding jumper service disco since EGC is brought.

I know I know main service disco must have main bonding jumper
 
He's wrong, and connecting it "properly" would result in parallel neutral-current pathways.
 
What's shown on the drawings doesn't matter, the POCO will install what they want to, it is not a concern for a plan reviewer.

Roger
 
I’ve seen some poco’s do that, some will use it, some just coil it up in the bottom of the transformer. Seems like it was southern Alabama, and maybe Arkansas I’ve seen it. Don’t know if it was a poco requirement, or just the engineer screwed up, and called for it on the prints. I just put back what I pull out.
 
roger said:
What's shown on the drawings doesn't matter, the POCO will install what they want to, it is not a concern for a plan reviewer.

Roger
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But that’s not an excuse not to have main bonding jumper in main service disco correct?The guy is saying in main service disco no main bonding jumper needed says EGC is brought from POCO
 
Roger is right in that there is little need for you to fret over it.
You are correct that 250.24(B) requires Main Bond Jumper.
(B) Main Bonding Jumper. For a grounded system, an unspliced main bonding jumper shall be used to connect the equipment grounding conductor(s) and the service-disconnect enclosure to the grounded conductor within the enclosure for each service disconnect in accordance with 250.28.
POCO will likely not pull it. A competent electrician will install the jumper. The plans should reflect the service panel Main Bonding Jumper.
About all you can do.
Move on !
 
Our poco would run 4/0 al for a 400 amp service! I had a customer that had such a severe voltage drop, it would be 100 volts when all the a/c’s were running. When I upgraded the service to 1200 amp, the poco wanted to run parallel 4/0 al! Met with the engineer, and negotiated parallel 350 kcmil. First summer with the new service, transformer blew. They left the old transformer, store load was almost doubled after addition, in which it blew a couple of weeks later!
 
hillbilly1 said:
Our poco would run 4/0 al for a 400 amp service! I had a customer that had such a severe voltage drop, it would be 100 volts when all the a/c’s were running. When I upgraded the service to 1200 amp, the poco wanted to run parallel 4/0 al! Met with the engineer, and negotiated parallel 350 kcmil. First summer with the new service, transformer blew. They left the old transformer, store load was almost doubled after addition, in which it blew a couple of weeks later!
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For a 400 amp service 4/0 is more than enough with given diversity. If the VD was that much the length was the problem.
also sounds like loads were added without discussion with the POCO.

Of course, that was dumb to leave the old transformer. Sounds like it was a “staker” you talked to instead of a real engineer. We have them also. Someone to get the job on paper. Some of the guys here call them bic pen linemen.
 
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