Siemens A37999 fault code meaning
Siemens / A37999
Series: G120-CU250S-2, S120-S150
HF Damper: Unknown alarm
converter
Meaning: HF An alarm that the control unit firmware cannot recognize has occurred on the damper. This fault may occur if the firmware on this component is newer than the control unit firmware.
Possible causes
Source: SINAMICS G120, Control Unit CU250S-2 P1618; SINAMICS S120_S150 P3216