These are provided over the windings
of the motor .The main function of heaters, is to heat the windings when motor
is in idle condition or kept in storage , in order to prevent moisture or dew settling
over the windings and thereby reducing the insulation resistance CAUTION-Supply
to the heaters must be switched off before switching on the motor. The motors
are provided with space heaters of ratings 25w, 40w, 50w, or 60w 240 V single
phase depending on the frame size. Like thermistors the space heater leads are
also brought in the main terminal box or in a separate
auxiliary terminal box.
