A comprehensive comparison between Standard Wire Gauge and American Wire Gauge.

In the world of electrical engineering and motor winding, two dominant measurement systems dictate wire sizes: SWG (Standard Wire Gauge) and AWG (American Wire Gauge). While they serve the same purpose, they are completely different scales.

SWG, sometimes known as Imperial Wire Gauge, is the standard across the United Kingdom, India, and many Commonwealth nations. AWG, on the other hand, is the strictly enforced standard in the United States and North America.

A common catastrophic mistake for beginners is assuming SWG 20 is identical to AWG 20. In reality, SWG 20 has a diameter of 0.914mm, whereas AWG 20 is significantly smaller at 0.812mm. Using an AWG wire when an SWG wire was specified will result in a much higher resistance coil, ruining the motors efficiency and thermal limits.