The diameter of the wire measured in MCM, (thousand circular mils). Wire sizes in the U.S. are described in AWG, (American Wire Gauge) such as #12 awg printed on the wire.
wire gauge is used to determine the size of the wire to be installed based on the amperage draw of whatever is being hooked up on the receiving end. ie 14 gauge is for a 15 amp circuit, 12 gauge is...