What is one key factor when determining the ampacity of a motor circuit?

Determining the ampacity of a motor circuit is primarily influenced by the motor horsepower. The horsepower rating of a motor provides essential information about how much power the motor consumes and, consequently, how much current (amps) it will draw under typical operating conditions. Ampacity calculations must ensure that the conductors supplying power to the motor are capable of handling this current without overheating or causing a safety hazard.

The relationship between horsepower and current draw is significant because different horsepower ratings will lead to different amp draw values, which must be considered to select the correct wire size and protection devices. Factors such as voltage and the physical characteristics of the conductors come into play as well, but the horsepower delivers the fundamental basis for understanding how much current will flow through the circuit during operation.