Originally Posted By: Bob Badger
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Hi Jeff I would say Robert is correct and that they are using parallel conductors, in this case two conductors per phase, the only reason for doing this for a ‘small’ service is to keep from having to bend larger conductors.
I do not bother until I get above 400 amps but to each their own. ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif)
For example if we build a 3000 amp service we generally run 8 sets of four 500 Kcmils in 8 separate pipes for a total of 32 conductors. You will not find single conductors rated 3000 amps.
Back to your picture it looks like they say 3/0 on them I can not tell if they are aluminum or copper.
If they are copper 3/0 is good for 200 amps x 2 = 400 amp service.
If they are Aluminum 3/0 is good 155 amps x 2 = 300 amp service. (you might be able to push this out to 350 amps by 'working' the code)
However they put them all in the same raceway which means that the wires need to be derated by 80%.
I will skip all the code references and technicality's but once I do the derating I come out with:
Copper 360 amps which could still be a 400 amp service or might have to be a 350 amp service, it all depends on the calculated load.
Aluminum 280 amps resulting in a 300 amp or 250 amp service.
Now WHY ARE THEY ALL WHITE
In this area this would not get connected but some power companys have odd rules.
Bob (AKA iwire)
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