It is great for the /power utility/ to run a 200A feed to your house or shop, since they are allowed much larger liberties on derating ampacity of the wires on their side. Once the power passes the meter and belongs to you, the derating on the wires is different - depending on the insulation (60C 75C 90C) it might be only good for 150A or
180A. Even less if you start figuring in voltage drop.
And the code might have big problems with the reduced gauge on he neutral, but I'm not going looking for the chapter and verse right now. You can use that reduced gauge wire as the safety ground and another piece of AL 4/0 for the neutral.
It is exactly what the power company recommends. In fact, it is the same brand, type, spec., etc. that they use for 200 amp. service. I already told them that I was running hundreds of feet and I wanted 200 amp. service.
Right - but that's from the utility transformer to the house main service. Once you go through the service panel you can't have a reduced ampacity neutral anymore, and you need a separate safety ground. You can have a second ground rod out at the shed but the grounds have to be tied together, no separately derived grounds.
You can use 4/0 Triplex IF you are putting a new service with a new meter at the shed - then you don't need to separate the ground and neutral. Normally the power utility supplies the service entrance wire in California since they are responsible for it. But if you want to go with larger wire so you don't start off with voltage drop, you are free to go larger - and should.
Depending on how many hundreds of feet to the transformer, you might need to go to 500MCM or even 750MCM so you still have 240V at the shed under full load.
To run a sub-feed out to a shed from the house service you would use the same stuff but in Quadplex lay-up with three 4/0 and the 2/0 safety ground - the utility would use this for a 3-phase service.
And depending on the distance between house and shed you would need to derate rather severely - past 200' I wouldn't go over 100A on 4/0.
So what? THey have no legal responsibility to provide you with good advice.
YOu should find out what your local AHJ says. Even though you are rural no where, you certainly have some one some where who has a legal authority, and obligation, to inspect it. [And they probably want you to have pulled a permit and paid a fee.]
Well, I am an e.e. so, I don't really need anyone to hold my hand about this. I just thought that I would tell Bruce that the power company uses just what I listed for their installations.
All I wanted to do is to offer others some wire at a very, good price, much below retail, should they wish to run heavy service to their shop/shed/building, house, tipi, cave, cavern, tunnel or whatever.
I could also get anal about it and ask the Supreme Court what they thought about it, too. :).
You see, I am not asking for advice although, I appreciate input; I am merely offering some leftover wire for sale that I almost stole.
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.