Code Quiz of Day

Motor Controller Functions

May 8, 2015

Article 430 covers motors, motor circuits and controllers.

A motor controller shall open all conductors to the motor where not used as a disconnecting means.

a) True
b) False

See answer and applicable Code reference

The correct answer is: b) False

Article 430 covers motors, motor circuits and controllers. Part VI of this Article focuses on motor control circuits. As per Sec. 430.84, "The controller shall not be required to open all conductors to the motor." An Exception notes: "Where the controller serves also as a disconnecting means, it shall open all ungrounded conductors to the motor as provided in 430.111."

About the Author

Mike Holt

Mike Holt is the owner of Mike Holt Enterprises (www.MikeHolt.com), one of the largest electrical publishers in the United States. He earned a master's degree in the Business Administration Program (MBA) from the University of Miami. He earned his reputation as a National Electrical Code (NEC) expert by working his way up through the electrical trade. Formally a construction editor for two different trade publications, Mike started his career as an apprentice electrician and eventually became a master electrician, an electrical inspector, a contractor, and an educator. Mike has taught more than 1,000 classes on 30 different electrical-related subjects — ranging from alarm installations to exam preparation and voltage drop calculations. He continues to produce seminars, videos, books, and online training for the trade as well as contribute monthly Code content to EC&M magazine.