MCC Buckets

New, Used, and Obsolete Motor Control Center Buckets

Motor Control Center (MCC) buckets are an integral part of all industrial power control and distribution systems. A typical motor control center for operating machines in a factory is housed within a Nema 12 enclosure, or higher Nema rating depending upon environmental conditions, with rows and columns of small doors on the front of the cabinet. Behind each of these doors resides an MCC bucket which connects the electrical components in the cabinet to the bus bars behind it.


The components contained within each MCC bucket can vary depending upon the various needs of factory. A common electrical configuration in the U.S. would be a line-up of three bus bars carrying 3-phase, 480 volt, 60 Hz electrical power. The buckets for this typical arrangement need to contain a circuit breaker, motor starter, and a control power transformer. All circuit breakers contained in MCC buckets will have a handle attached through the door allowing power to be shut off without opening the cabinet.

MCC buckets are modular in nature to fit in columns within the control cabinet. The average size bucket is 18 inches wide and 12 inches tall and will house the typical circuit breaker, motor starter, and power transformer combination. Taller enclosures are available for housing soft starters and variable frequency drives. Motor control center buckets are designed to be removable for ease of work outside the motor control center cabinet.

OSHA requires that the bucket door have a handle attached to the circuit breaker inside and a latch to secure the breaker in the off position. Power and function indicators may be set on the bucket door or a reset button for the motor starter. Bay Breakers is also home to a great selection of motor controls, and other electrical components for a host of demanding jobs.

The way MCC buckets are being used in industrial electrical control is changing rapidly. The contents of the unit are dependent upon the industrial application at hand. Many years ago the motor control centers housed every control for motors in the industrial setting. The current trend is using the centers only as points for power distribution to electrical panels. In these situations, the MCC bucket will contain only a circuit breaker and a handle for power shut down.