Siemens SINAMICS S150 NEMA, Operating Instructions Manual, Page: 544 / 862

Functions, monitoring and protective functions
9.3 Drive functions
Enclosed Drives
542
Operating Instructions, 12/2018, A5E36652151A
Function diagram
FP 7016 Technology functions - Internal armature short circuit
Parameters
•
p0300:
Mot type selection
•
p1230
BI: Armature short-circuit/DC braking activation
•
p1231
Armature short-circuit/DC braking configuration
• 4: Internal armature short-circuit/DC braking
• r1239
CO/BO: Armature short-circuit/DC braking status word
9.3.10.4 DC braking
Description
DC braking is only available for induction motors. It is used preferably when braking in a
hazardous situation, if controlled braking via the drive is no longer possible (for example, in
the event of a power failure, an EMERGENCY OFF, etc.) or if no regenerative infeed is
used.
DC braking is activated via p1231 = 4 or via p1231 = 14. It can be initiated via an input signal
p1230 (signal = 1) or a fault response.
WARNING
Motor accelerates uncontrollably for pulling loads
For pulling loads, when DC braking is used, during the demagnetization time, the motor can
accelerate uncontrollably. This can result in severe injury or death. An additional supporting
mechanical brake is only closed after the demagnetization time – when the motor is already
rotating – and therefore does not prevent the motor from accelerating uncontrollably.
• Do not use DC braking for pulling loads.
Activation of DC braking via input signal
p1231 = 4 (internal armature short-circuit/DC braking)
If DC braking is activated by the digital input signal, the first step is that the pulses are
blocked for the duration of the demagnetization time (p0347) of the motor in order to
demagnetize the motor – the parameter p1234 (speed at the start of DC braking) is ignored.
Then the braking current (p1232) is applied as long as the input is initiated in order to brake
the motor or hold it at standstill.