Profile: Mawdsleys BER Ltd specializes in the design, manufacture and repair of rotating electrical equipment, including AC and DC motors. We repair all models and brands of motors. Our motor rewinds service encapsulates the rewind, repair and refurbishment of rotating equipment including AC motors, DC motors, alternators and generators. Carbon is a soft metal and brushes are designed to wear out over time, the reason a soft metal is used is to reduce the amount of damage caused to the commutator through friction.