Safety Input - Siemens sinamics G120 Operating Instructions Manual

Installing
4.6 Installing Control Unit
4.6.7

Safety input

Which devices are you allowed to connect?
The safety-related input is designed for the following devices:
● Connection of safety sensors, e.g. emergency stop command devices or light curtains.
● Connection of pre-processing devices, e.g. fail-safe control systems and safety relays.
Signal state
The inverter expects signals with the same state at its safety-related input:
● High signal: The safety function is deselected.
● Low signal: The safety function is selected.
Connect P/P and P/M-switching safe outputs
PP-switching output
Fault detection
The inverter evaluates deviations in the two signals of the safety-related input. The inverter
thus detects, for example the following faults:
● Cable break
● Defective sensor
The inverter cannot detect the following faults:
● Cross-circuit of the two cables
● Short-circuit between signal cable and 24 V power supply
Special measures to prevent cross-circuits and short-circuits
The routing of cables over longer distances, e.g. between remote control cabinets, increases
the risk of damaging cables. Damaged cables raise the risk of an undetected cross-circuit
with power-conducting cables laid in parallel. A cross-circuit can cause interruption to the
transfer of safety-related signals.
To reduce the risk of cable damage, you need to lay signal lines in steel pipes.
102
It is permissible to connect PP and PM-
switching safe outputs to a safe input.
PM-switching output
Operating Instructions, 01/2016, FW V4.7 SP6, A5E31759476B AE
Converter with CU250S-2 Control Unit