Fanuc alarm SV0307: APC ALARM: MOVEMENT EXCESS ERROR
servo APC alarm (absolute pulse coder) · Fanuc 0i-D
What it means
The machine moved excessively around power-up, so the relationship between the absolute detector count and machine position could not be established correctly. Common triggers are axis drift under gravity (vertical or overhanging axes with failed brakes), someone rotating a motor/shaft by hand, or a clutch that slipped while power was off. After correcting the physical cause, perform a reference return to restore the absolute reference.
Likely causes
- Axis sagged or drifted during power-off (worn brake, counterbalance fault)
- Motor or shaft turned manually while power was off
- Loose coupling between motor and ballscrew
- Machine moved by external force
Need the part urgently?
Send us alarm SV0307 with your machine details — typical RFQ turnaround is 24–48h.