0891

Common Causes

• Incorrect sensor zero offset (codes 1, 3)
• Faulty servo data file (code 4)
• Loose motor coupling (codes 5, 6)
• Faulty motor encoder, shaft-mounted encoder or absolute scale
• Control PCB of the inverter unit

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code 1 = Linear axis division stroke over; sensor zero offset often incorrect.; code 2 = Semi-closed loop position [pr] to [pf] conversion overflow.; code 3 = Underflow in composition; sensor zero offset often incorrect.; code 4 = Overflow in composition; servo data file often faulty.; code 5 = Hybrid control input overflow; motor coupling often loose.; code 6 = Overflow in hybrid control initialization; motor coupling often loose.
2. 2Read the code: 1 linear axis division stroke over; 2 semi-closed loop position conversion overflow; 3 underflow in composition; 4 overflow in composition; 5 hybrid control input overflow; 6 overflow in hybrid control initialization.
3. 3For codes 1 or 3, suspect an incorrect sensor zero offset: check and re-set the encoder/scale zero offset for the named axis.
4. 4For code 4, the servo data file is often faulty: reload the correct servo data file for the axis.
5. 5For codes 5 or 6, check the motor coupling for looseness: a slipping coupling corrupts the position calculation, so tighten or replace the coupling.
6. 6If these checks do not clear it, inspect the motor encoder, shaft-mounted encoder or absolute scale and the inverter unit control PCB, then re-home the axis and verify position calculation.