Siemens SINAMICS G120XA - DC Braking When Falling below a Starting Speed; DC Braking When a Fault Occurs

6.6.4.1 DC braking
Function description
NOTICE
Motor overheating as a result of DC braking
The motor will overheat if you use DC braking too frequently or use it for too long. This may
damage the motor.
● Monitor the motor temperature.
● Allow the motor to adequately cool down between braking operations.
● If necessary, select another motor braking method.
With DC braking, the converter outputs an internal OFF2 command for the time that it takes to
de-energize the motor p0347 - and then impresses the braking current for the duration of the
DC braking.
The DC-braking function is possible only for induction motors.
4 different events initiate DC braking
DC braking when falling below a starting speed
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Precondition:
p1230 = 1 and p1231 = 14
Function:
1. The motor speed has exceeded the
starting speed.
2. The converter activates the DC braking as
soon as the motor speed falls below the
starting speed.
DC braking when a fault occurs
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Precondition:
Fault number and fault response are assigned
via p2100 and p2101.
Function:
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.
Advanced commissioning
6.6 Motor control
SINAMICS G120XA converter
Operating Instructions, 03/2019, FW V1.0, A5E44751205B AB 297