EC&M Tech Talk — Motor Installation

In this episode of Tech Talk, Randy Barnett covers the major topics from Art. 430 Motors, Motor Circuits, and Controllers. The video follows a logical sequence for installing motors:

1. Sizing conductors – how to use the Art. 430 tables and Sec. 310.16 to determine ampacity requirements.
2. The motor and controller disconnect location requirements
3. Sizing short circuit and ground fault protection and the use of time-delay fuses
4. Overload protection for the motor
5. Sizing the motor controller, or motor starter
6. Using Table 250.122 to size the equipment grounding conductor
7. Using Table 110.28 to select the proper type disconnect enclosure Numerous NEC references are found on the screen throughout the video.

Explanations of continuous duty motors and motor starters is also provided. At the beginning of the video reference is made to NEC Informative Annex section D.8. This example of installing a 25 horsepower motor is the basis for this Tech Talk. Viewers can easily refer to D.8 at a later date to refresh themselves on these NEC requirements.