Aluminum wire

[david luchini]

I disagree. Since no conductor material is specified, 110.5 says it has to be copper. If 310 precluded that, there would be no need for 110.5.

110.5 says conductors shall be copper unless otherwise provided for in the code. 310.2 provides for using aluminum, copper-clad aluminum, and copper conductors for general wiring. Seems pretty straightforward to me.

110.5 requires that flexible cables and fixture wires use copper conductors because nothing else in the code provides for using aluminum for those specific conductors.