Siemens SINAMICS S120 Commissioning Manual page 367

These attributes for differentiating the alarms are assigned to the appropriate alarm
numbers. The reaction to the existing alarm classes in the alarm is defined by the user
program in the higher-level control.
Explanations of the alarm classes
● Alarm class A: Drive operation currently not limited
– E.g. alarm when measurement systems inactive
– No limitation on current movement
– Prevent possible switching to the defective measuring system
● Alarm class B: Time-limited operation
– E.g. prewarning temperature: Without further action the drive may need to be switched
– After a timer stage -> additional fault
– After exceeding a switch-off threshold -> additional fault
● Alarm class C: Functionally limited operation
– E.g. reduced voltage/current/torque/speed limits (i2t)
– E.g. continue with reduced accuracy / resolution
– E.g. continue without encoder
Commissioning with Startdrive
Commissioning Manual, 11/2017, 6SL3097-4AA10-0BP1
off
Diagnostics
5.4 Fault and alarm messages
367