Siemens SINAMICS G150 Operating Instructions Manual page 453

DC braking as a fault response
Activation via p0491 = 4, p2101 = 6 (armature short-circuit, internal/DC braking)
If DC braking is activated as a fault response, the motor is initially braked in field-oriented
mode along the braking ramp up to the threshold set in p1234 (speed at the start of DC
braking). The slope of the ramp is identical with that of the OFF1 ramp (parameterized using
p1082, p1121). Subsequently, the pulses are disabled for the period in p0347
(demagnetizing time) in order to demagnetize the motor. DC braking will start for the duration
set in p1233 (DC braking duration).
● If an encoder is present, braking will continue until the speed drops to below standstill
● If no encoder is present, only the period in p1233 is effective.
Activation via p1231 = 5 (DC braking for OFF1/OFF3)
DC braking is activated with OFF1 or OFF3
● If the motor speed ≥ p1234, the motor is braked down to p1234. As soon as the motor
● If the motor speed at OFF1/OFF3 is already < p1234, the pulses are immediately
DC braking is activated for the period set in p1233 (DC braking duration), then switched off.
When OFF1/OFF3 is prematurely canceled, then normal operation is resumed.
DC braking as emergency braking of a fault response remains active.
Function diagram
FP 7017
Converter cabinet units
Operating Instructions, 03/2012, A5E03263466A
threshold p1226.
speed is < p1234, the pulses are disabled and the motor is demagnetized.
inhibited and the motor is demagnetized.
Technology functions - DC braking
Functions, Monitoring, and Protective Functions
9.2 Drive Functions
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