Crompton Controls 3DPM1CHS/10 - Manual (Page 10)

10
Direct on Line starter with S10 Brake Module
1 phase
NOTE: On braking there is a diode in the brake circuit connected directly across the motor.
Single phase induction motors have capacitors, permanent capacitors can be dc injected
and the diode needs to be rated for the discharge currents of the motor capacitors this
current can also produce a torque pulse on the shaft.
The capacitance in circuit prolongs the decay of electrical energy in the motor so a longer
dwell time is required from pressing the stop button to connecting the brake.
Capacitors can be short time rated and if so it is better to remove them from circuit
during braking.To remove the capacitors during braking use a normally closed auxiliary
contact on the brake contactor.
Aux contacts normally carry a 10 Amp rating and this may not be sufficient for the start
winding current for some single phase motors. The normally closed contact allows the
capacitor energy to discharge through the motor wining as normal otherwise a bleed
resistor would be needed.