Maximum Pull Tension

Pulling cables through conduit requires force. If that force exceeds the tensile strength of the copper, the conductor will stretch, neck down, and permanently lose ampacity.

Tension Limits (Copper)

The standard industry limit for pulling tension on copper conductors is 0.008 lbs per circular mil (cmil).

AWG	Circular Mils (cmil)	Max Tension (lbs) per Conductor
14	4,110	32.8
12	6,530	52.2
10	10,380	83.0
8	16,510	132.0
6	26,240	209.9
4	41,740	333.9

Formula for Multiple Conductors:

Max Tension = N × cmil × 0.008

Where N is the number of conductors. If pulling more than 3 conductors, the force is rarely distributed evenly. Derate the total by multiplying by 0.8.