'Nother xfmr question: 480 Wye 3-Phase to 240

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Smart $ said:
???
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That's what I was asking, just to check myself.

IF this was a 3-phase xfmr, which it isn't, then the secondaries would have four wires plus the e.g.: three lines and the neutral. Wouldn't the neutral be considered a current carrying conductor for pipe fill and, as such, require an .80 adjustment fill factor for deration?
 
The average Joe doesn't realize there is a difference in wiring needs between a 3 hp, a 30 hp or a 300 hp machine. They all think you are going to just run wiring to a receptacle and they will just plug the thing in, no matter which one it is. Maybe will only take a couple hours and you should be done:roll:
 
Richardh247 said:
That's what I was asking, just to check myself.

IF this was a 3-phase xfmr, which it isn't, then the secondaries would have four wires plus the e.g.: three lines and the neutral. Wouldn't the neutral be considered a current carrying conductor for pipe fill and, as such, require an .80 adjustment fill factor for deration?
Click to expand...
If a three phase transformer is a delta, there are three CCCs. If it is a wye there are four circuit conductors and the neutral would not be a CCC even for line to line loads unless non linear.
Pipe fill counts all wires. Derating (ampacity adjustment) counts only CCCs.
 
GoldDigger said:
If a three phase transformer is a delta, there are three CCCs. If it is a wye there are four circuit conductors and the neutral would not be a CCC even for line to line loads unless non linear.
Pipe fill counts all wires. Derating (ampacity adjustment) counts only CCCs.
Click to expand...

And now, under the 2014, one also counts the spares. Surprised me.

ice
 
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