derating question more then 3 conductors in conduit

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infinity said:
There aren't many occasions where the major portion of the load is non-linear. If this is mixed use IMO the neutral is not a CCC.
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I agree, however a computer is a non-linear load and if there were a lot of them that might make a difference.

Edit: How would you proove something like this? If you checked the current draw on the neutral that would be after the circuits are run.:?:blink:
 
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lets play it safe the neutral is a ccc
2/0
195amp x 80% =156 amp x 1.0 = 156 amps
the correct size for 150 mcb in a panel from secondary side of transformer
 
Little Bill said:
I agree, however a computer is a non-linear load and if there were a lot of them that might make a difference.

Edit: How would you proove something like this? If you checked the current draw on the neutral that would be after the circuits are run.:?:blink:
Click to expand...
You would need to measure it with equipment that can read the effects that will be contributed by additive harmonic currents in that neutral. Average amp clamp meter will not show you this. I'm no expert on harmonics but at very least you will need to measure with a true RMS meter, not sure if it will show you what the real deal is with this conductor though.

grumpy11 said:
lets play it safe the neutral is a ccc
2/0
195amp x 80% =156 amp x 1.0 = 156 amps
the correct size for 150 mcb in a panel from secondary side of transformer
Click to expand...
Nothing wrong with playing it safe. If high harmonics are expected some may even run a neutral that is larger than the ungrounded conductors, we are probably talking a data center or similar install in most of those cases.
 
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