Siemens PM330 Hardware Installation Manual page 134

Appendix
A.3 Application examples for functional safety (STO / SS1-t)
Scenario 4:
● LED 1 DEVICE is OFF
-> group fault
● LED 2 OUT is OFF
-> the safety circuit is not enabled
● LED 3 IN flashes yellow
-> group fault, input circuit
● LED 4 SF is lit red
-> group fault
Possible causes:
● Group fault, cross-circuit fault in the input circuits
Scenario 5:
● LED 1 DEVICE is lit green
-> power supply, power up and configuration are OK
● LED 2 OUT flashes green
-> feedback circuit fault
● LED 3 IN flashes green
-> feedback circuit fault
● LED 4 SF flashes red
-> fault
Possible causes:
● Interruption in the feedback circuit wiring
● Incorrect feedback circuit wiring
● PM330 fault
– PM330 power supply missing -> establish the power supply
– One or two of the STO inputs of the PM330 has a high signal, e.g. as a result of short
– One or two switch-off signal paths of the PM330 is/are defective
– One or two feedback signal paths of the PM330 is/are defective
132
circuit or cross circuit fault in the wiring
Hardware Installation Manual, 12/2018, A5E32844552B AF
Power Module PM330