What is Circular-Mil (cmil)?
Circular-Mil (cmil) is a specialized unit of area commonly used in the electrical industry to measure the cross-sectional area of round conductors, like wires and cables. One circular mil is the area of a circle with a diameter of one mil (one-thousandth of an inch). This unit simplifies calculations involving wire size and electrical resistance.
In residential and commercial electrical systems, specifying wire size using cmil is crucial for ensuring the wire can safely carry the expected current without overheating. For example, a wire with a larger cmil rating can carry more current with less resistance and voltage drop. Electricians often refer to charts or ampacity tables where wire sizes are listed in cmil to determine proper wire gauge for specific electrical loads.
