Maintaining you motor control centre (MCC) for dust, pests, and insects can make the service life greatly increased. A regularly scheduled vacuum and cleaning can reduce problems when you can’t afford them.
Included in cleaning is checking for hot spots, both in the bus and contractors, heat is an early indication of a failure about to happen. In most cases re-tightening the bolts and screws is enough to mitigate the issue, but sometimes a disassembly is needed to determine the reason for the hot spots.
As the MCC’s age, handle function starts to fail, the reset levers no longer reach, and contactors and overloads reach their life’s end. It also a good thing in critical systems to replace these control hardware before they fail and leave the plant down. It can take quite to planning to choose when to replace the parts, but if one type of control is failing with some consistence, it probably time to change all the similar components in the system.