Advanced commissioning
7.8 Application-specific functions
Converter with control units CU250D-2
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Operating Instructions, 04/2015, FW V4.7.3, A5E34261542B AB
7.8.4
Motor holding brake
The motor holding brake holds the motor in position when it is switched off. If the setting is
correct, the motor will produce an electrical holding torque before the inverter opens the
brake. The inverter does not close the motor holding brake until the motor is at a standstill.
Function
Figure 7-50 Motor holding brake function
Function after an ON command:
1.
With the ON command, the inverter switches the motor on.
2.
At the end of the "motor excitation build-up time" (p0346), the inverter issues the
command to open the brake.
3.
The inverter keeps the motor at a standstill until the "motor holding brake opening time"
p1216 has ended.
The motor holding brake must be opened within time p1216.
4.
The inverter accelerates the motor to the speed setpoint.
Function after an OFF1 or OFF3 command:
1.
The inverter brakes the motor down to a standstill and switches it off using the OFF1 or
OFF3 command.
2.
When braking, the inverter compares the speed setpoint and the actual speed with the
"standstill detection speed threshold" p1226:
–
Speed setpoint < p1226: The "standstill detection monitoring time" p1227 starts
–
Current speed < p1226: The "pulse cancellation deceleration time" p1228 starts
