Siemens CU240B-2 - Page 286

Advanced commissioning
6.7 Application-specific functions
Converter with the CU240B-2 and CU240E-2 Control Units
286 Operating Instructions, 01/2016, FW V4.7 SP6, A5E34259001B AC
DC braking initiated using a control command
Precondition: p1231 = 4 and p1230 = control
command, e.g. p1230 = 722.3 (control command
via DI 3)
DC braking when switching off the motor
Precondition: p1231 = 5 or p1230 = 1 and p1231
= 14
DC braking when falling below a starting speed
1. The motor speed has exceeded the starting speed.
2. The inverter activates the DC braking as soon as the motor speed falls below the starting
speed.
DC braking when a fault occurs
1. A fault occurs, which initiates DC braking as response.
2. The motor brakes along the down ramp to the speed for the start of DC braking.
3. DC braking starts.
DC braking initiated by a control command
1. The higher-level control issues the command for DC braking, e.g. using DI3: p1230 =
722.3.
2. DC braking starts.
If the higher-level control withdraws the command during DC braking, the inverter interrupts
DC braking and the motor accelerates to its setpoint.
DC braking when the motor is switched off
1. The higher-level control switches off the motor (OFF1 or OFF3).
2. The motor brakes along the down ramp to the speed for the start of DC braking.
3. DC braking starts.