Internal Voltage Protection - Siemens SINAMICS S120 Function Manual

7.12.3

Internal voltage protection

With the integrated voltage protection is active, after the pulses have been canceled, all the
motor terminals are at half of the DC link potential (without integrated voltage protection the
motor terminals have a no voltage condition)!
● Only short-circuit proof motors must be used (p0320 < p0323).
● The Motor Module must be able to withstand the 1.8-fold short-circuit current (r0320) of
the motor (r0209).
● The internal voltage protection function cannot be interrupted due to a fault response. If
an overcurrent occurs while internal voltage protection is active, the Motor Module and/or
the motor might sustain irreparable damage.
● If the Motor Module does not support the autonomous, integrated voltage protection
mechanism (r0192.10 = 0), an external 24 V supply (UPS) must be provided for the
components to ensure reliable operation in the event of mains power failure.
● If the Motor Module supports the autonomous, integrated voltage protection mechanism
(r0192.10 = 1), the 24 V supply for the components must be implemented via a Control
Supply Module to ensure reliable operation in the event of mains power failure.
● When the internal voltage protection function is active, the motor must not be powered by
an external source for an extended period of time (e.g. by loads that move the motor or
another coupled motor).
Setting
The internal voltage protection is set with p1231 = 3.
Activation
The function is activated and initiated if the signal source of p1230 is set to a "1" signal.
Deactivation
The function is deactivated if the signal source of p1230 is set to a "0" signal. When triggered
by a fault, the fault must have been removed and acknowledged.
Drive functions
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
7.12 Armature short-circuit, DC braking
Basic functions
347