Siemens 3RK1308‑0 00‑0CP0 Series Equipment Manual page 49

The switching on and off routines must be run through without errors. This means:
● Current must flow.
● The motor starter must not display any errors.
● The supply voltage must be stable.
The switching on or off routine is canceled as soon as an error is detected. The motor starter
assumes the safe OFF state. Observe to the diagnostic messages in DS72 logbook - Read
device error (Page 180). Depending on the error message, you can reset the error by
switching off the 24 V supply voltage and then switching it on again.
If you switch on when the line voltage is interrupted or a load is missing, the following
messages are generated:
● Residual current detected
● Residual current disconnection
This message can be acknowledged by the Trip Reset / Reset pushbutton.
If the supply voltage is interrupted during switching on or off, this may lead to a device fault
(entry 308 in data set 92 (Page 186)). In addition, the following entries in DS72 logbook -
Read device error (Page 180) are possible:
● 20017 "Residual current detection during switching on/off routine or bypass element does
not close"
● 20018 "Error in switching element diagnostics in the switching off process"
You can reset these faults and subsequently continue operating the motor starter following a
fault-free test cycle as described above. If the faults recur, this indicates that the motor
starter is defective in spite of the fact that the supply voltage conditions are stable. Replace
the motor starter in this case.
Replacing the fail-safe motor starter
When replacing a fail-safe motor starter, pay attention to the commissioning specifications
for fail-safe systems.
Motor starter (3RK1308‑0**00‑0CP0)
Equipment Manual, 11/2019, A5E34821005002A/RS-AC/003
Product features
5.8 Operating motor starters
49