Siemens SINAMICS G120 Operating Instructions Manual page 259

Table 10- 4
LED BF display for CANopen
In addition to the signal states "on" and "off" there are three different flashing frequencies:
Table 10- 5
GREEN - single flash Bus state "Stopped"
RED - single flash
RED - double flash
SINAMICS G120C Inverter
Operating Instructions, 01/2011, FW 4.4, A5E02999804A AB
Diagnostics of the safety functions
SAFE LED Meaning
YELLOW - on One or more safety functions are enabled, but not active.
YELLOW - slow One or more safety functions are active; no safety function faults have
occurred.
YELLOW - rapid The converter has detected a safety function fault and initiated a STOP
response.
Communication diagnostics via CANopen
BF LED Explanation
GREEN - on Bus state "Operational"
GREEN - fast Bus state "Pre-Operational"
RED - on No bus
Alarm - limit reached
Error event in control (Error Control Event)
Alarms, faults and system messages
10.1 Operating states indicated on LEDs
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