Motors, Motor Circuits, and Controllers

There must be an individual disconnecting device for each controller. A disconnecting means must be located within sight, visible, and within 50 feet of the controller location.

If the controller is marked with a warning label that gives the location and identification of the disconnecting means that is to be locked in the open position, then the controller disconnection means for motor branch circuits over 600 volts, nominal, can be out of sight of the controller.

The disconnecting device must disconnect the motor and the controller from all ungrounded supply conductors and be designed such that no pole can be operated independently.

An individual disconnecting means must be provided for each motor, but a single disconnecting means can be used for a group of motors if any of the following conditions are met:

• If a number of motors drive special parts of a single machine or piece of apparatus, such as a metal or woodworking machine, crane, or hoist
• If a group of motors is under the protection of one set of branch-circuit protective devices
• If a group of motors is in a single room in sight from the location of the disconnecting means

Specific requirements apply to groups of motors in a single room and are outlined in 29 CFR 1926.405.

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