Electric motors convert electricity into useful energy that keeps much of the world working. From refrigerators in homes to motors operating large machines in manufacturing plants, electric motors provide necessary power. In...
I recently had new air conditioner units and a new swimming pool circulation motor installed at my home. The installer asked if I wanted soft or hard start units installed on these motors for a nominal fee. Not knowing that I...
Jim Dollard has an extensive background in codes and standards. If you have a query about the National Electrical Code (NEC) , Jim will help you solve it. Send questions to codefaqs@gmail.com. Answers are based on the 2017...
Fire and safety issues, wasted energy, unexpected breakdowns, unnecessary wear on equipment, early replacement—these are some of the serious and costly problems that can result from improperly operating electric motors. To...
Jim Dollard has an extensive background in codes and standards. If you have a query about the National Electrical Code (NEC) , Jim will help you solve it. Send questions to codefaqs@gmail.com. Answers are based on the 2017...
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...
As stated in 240.4 in the National Electrical Code (NEC), conductors, other than flexible cords, flexible cables and fixture wires, shall be protected against overcurrent in accordance with their ampacities specified in 310...
Article 430 in the National Electrical Code (NEC) covers motors, motor branch-circuit and feeder conductors and their protection, motor overload protection, motor control circuits, motor controllers, and motor control centers...
Whether performing a load calculation for hundreds of motors in an industrial plant or installing a swimming pool pump in a single-family dwelling, it is important to reference provisions and tables in Article 430 of the...
As the first sentence of the National Electrical Code (NEC) states, the Code’s purpose is the practical safeguarding of people and property from hazards arising from the use of electricity [90.1(A)]. This first section...
Recently, a question came up about applying the National Electrical Code (NEC) to achieve minimum compliant overcurrent protection for a general motor circuit to protect both the motor and conductors. This column reviews the...
Article 430 in the National Electrical Code (NEC) covers motors, motor branch-circuit and feeder conductors and their protection, motor overload protection, motor control circuits, motor controllers, and motor control centers...
Chapter 4 of the National Electrical Code (NEC), Equipment for General Use, contains 22 articles. Some of the articles include provisions pertaining to switches, receptacles, switchboards and panelboards, industrial control...