A motor control center (MCC) is an assembly to control some or all electric motors in a central location. It consists of multiple enclosed sections having a common power bus and with each section containing a combination starter, which in turn consists of motor starter, fuses or circuit breaker, and power disconnect. A motor control center can also include push buttons, indicator lights, variable-frequency drives, programmable logic controllers, and metering equipment. It may be combined with the electrical service entrance for the building.

MCC's are typically found in large commercial or industrial buildings where there are many electric motors that need to be controlled from a central location, such as a mechanical room or electrical room.

Commissioning procedure for motor control center

• Make sure that all the pre-commissioning verifications are executed effectively.
• The incoming supply of the Motor Control Center shall be measured for current, voltage, frequency & phase sequence
• The outgoing feeders shall be energized one by one and the supply shall be measured for voltages
• Check the metering functions for proper operation and correct readings
• Check the functionality of starters in manual mode
• By keeping the selector switch in AUTO mode check the functionality of starters by simulation
• Check the earth leakage trip facility
• Check incomer trip setting
• Check over load relay setting
• Check timer setting