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Current carrying conductor

Current carrying conductor

Current carrying conductor

(OP)
I am fairly new to NEC and I am trying to find their definition of a 'current carrying conductor', specifically, is the control wiring (say coil on starter/contactor) considered to be a current carrying conductor (for conduit fill)? Some claim it is not, but I believe it is.
I searched in an old version of NEC (93) and can't find anything, including on the net.

RE: Current carrying conductor

Look at Exception #1 to Note 8 to the 0-2000 volt ampacity tables in the '93 NEC.  This exception only requires that the power and lighting conductors be counted for derating purposes.  The control wiring would not need to be counted.  
Don

RE: Current carrying conductor

(OP)
This seems reasonable to me in most circumstances to discount the control wiring. Is there some magic cut-off current draw where the wiring can be ignored? I can imagine cases where the control current could be significant in relation to the power and lighting circuit current in the same conduit, ie say control current is 10A and lighting current is 12A. It would not make sense to classify the control current as not being a current carrying conductor since it will contribute significantly to the overall heating of the wires in the conduit. Any other comments in regards to my statements? Thank you.

RE: Current carrying conductor

The only instance where control current would be 10A is when you are supplying multiple control circuits with power. This would then be a power circuit.
Control wiring is used to connect switches and contacts, and contactor & relay coil loads are usually the largest(or only) real currents involved. A single contactor coil carrying 10A? This would be very uncommon.

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