Troubleshooting For Encoders - Siemens SINAMICS S120 Commissioning Manual

Explanations of the alarm classes
● Alarm class A: Drive operation currently not limited
● Alarm class B: Time-limited operation
● Alarm class C: Functionally limited operation
3.6

Troubleshooting for encoders

If an encoder fault is present, it can be acknowledged separately according to encoder
channels in a PROFIdrive telegram via the encoder interface (Gn_STW.15) or the drive
interface of the appropriate DO.
Sample configuration: 2-encoder system
● Encoder G1 motor measurement system
● Encoder G2 direct measurement system
Case considered:
All encoders signal encoder faults.
● The errors are entered in the encoder interface - and from there into the encoder channel
● The faults are transferred to the drive DO.
● Motor measuring system faults set the drive DO to fault (ZSW1 bit3), the faults are
● The direct measuring system faults are re-addressed as alarms via the appropriate drive
Commissioning Manual
Commissioning Manual, (IH1), 01/2011, 6SL3097-4AF00-0BP1
– e.g. alarm when measurement systems inactive
– no limitation on current movement
– Prevent possible switching to the defective measuring system
– e.g. prewarning temperature: without further action the drive may need to be switched
off
– After a timer stage -> additional fault
– after exceeding a switch-off threshold -> additional fault
– e.g. reduced voltage/current/torque/speed limits (i2t)
– e.g. continue with reduced accuracy / resolution
– e.g. continue without encoder
n of the PROFIDRIVE telegram. Bit15 of the encoder status word (Gn_ZSW.15 = 1).
additionally signaled via the drive interface. An entry is made in fault buffer p0945. The
parameterized fault reaction is initiated internally.
DO and signaled via the drive interface (ZSW1 bit7). An entry is made in alarm buffer
r2122.
No drive reactions are initiated.
Diagnostics
3.6 Troubleshooting for encoders
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