Various Cause of the Motor Noise
When a motor runs, the commutator switches the direction of the electricity that flows in the
windings. Though the system keeps the motor running, occasional spark occurs between brushes
and commutator at the timing of the commutation. The spark is one of the causes of the
electrical noise.
Especially when the motor starts from its stalled position, comparably higher current, or a
stall current, flows into the windings. Higher current usually causes higher noise.
Also the similar noise happens when (1) brushes stays unstable on the surface of the
commutator, (2) the input to the motor is much higher than expected (3) and so on.
Other factor may be an insulation created on the commutator surface, which results in unstable
flow of the electricity. Visit us for more information www.ttmotor.com thanks.