What is the purpose of Article 430 in the NEC?

Article 430 in the National Electrical Code (NEC) is titled “Motors, Motor Circuits and Controllers.” As the scope of the article states, it covers motors, motor branch-circuit and feeder conductors, motor branch-circuit and feeder protection, motor overload protection, motor control circuits, motor controllers, and …

What section of code article 430 is used to size the short-circuit and ground-fault protection for a single motor?

Motor overcurrent protection. Part IV of NEC Article 430 lists the requirements for motor overcurrent protection. This includes branch circuit short circuit and ground fault protection for the motor, the motor control equipment and the conductors.

What is a motor controller NEC?

For the purpose of Article 430, a controller is any switch or device that is normally used to start and stop a motor by making and breaking the motor circuit current [430.2].

What is an inverse time breaker?

An inverse time circuit breaker is a device that protects your branch circuit’s motors. It acts as protection from electronic problems such as short circuits and overloads.

How do you size A motor overload?

You must size the overloads no more than 115% to 125% of the motor nameplate current rating, depending on the conditions [430.32(A)(1)]. You must size the short-circuit ground-fault protection device from 150% to 300% of the motor FLC [Table 430.52].

How do you determine engine breaker size?

Circuit Breaker Size Calculation for Continuous & Non-contentious Load

= 125% Continuous Load + 100% Non-continuous load.
= (1.25 x 28A ) + (30A)
= 75A.

What size motor needs overload protection?

Motors with a nameplate service factor (SF) rating of 1.15 or more must have an overload protection device sized no more than 125% of the motor nameplate current rating.

What is Article 100 in the NEC?

Article 100 defines a Grounded Conductor as – A system or circuit conductor that is intentionally grounded. This definition is undoubtedly correct, but as previously stated, a Grounding Conductor (aka Equipment Grounding Conductor) is ALSO grounded.