F878Fault · MotionUsually repairable
Indramat DKC F878: Velocity Loop Error
What F878 means
The velocity loop is not following: the drive is at full current but the motor speed is far from the command.
Symptoms
Fault during acceleration or right after enable; the axis may jump.
Is it repairable?
Yes: encoder alignment and drive control repairs.
Common causes
- Motor power cable phases swapped
- Encoder fault or wrong commutation
- Failed drive control section
- Mechanical jam
Safe checks
- 1Check the motor phase order
- 2Check the encoder cable
- 3Check the axis moves freely with power off
Drives hold dangerous voltage after power-off. Checks should only be done by qualified personnel, with power isolated and the DC link discharged.
Reviewed by AutomIQ repair technicians. Code and name from the ECODRIVE DKC and ECODRIVE03 diagnostic descriptions.
Related Indramat DKC faults
- F218Amplifier overtemp. shutdown
- F219Motor overtemp. shutdown
- F226Undervoltage in power section
- F281Mains fault
- F822Encoder 1 failure: signal too small
- F860Overcurrent: short in power stage