KCMIL - vers - AWG

KCMIL(metric) is a fairly recent addition. Before that it was MCM(roman). Awg (American wire gauge) is the standard here in the U.S. but only goes so big, 4/0.

Why / When did the term kcmil come into being ?? Any comments or links would be appreciated.

Cheers, Alan

The correct unit is all lower case "kcmil". MCM means the same thing, and is upper case. They both represent "thousand circular mils" area. NEC table

310-16 changed units from MCM to kcmil in the 1990 code, but wire manufacturers use MCM.

Ben Miller

Thanks for the info ... does the "mil" actually stand for Millimeters ??

Hi Ben, kcmil is a measure of area in circular mils. 1 cmil represents the area of a circle who's diameter is 1/1000 inch. A 500 kcm cable, has an area equivalent to 500,000 circles, each with a diameter of 1/1000 inch. I think.

It's not metric Robert

Your reply should have been addressed to Alan, who asked the question.

Ben Miller