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Access NCK Diagnosis → Axis [axis name] → Encoder tab or use HMI menu path: Diagnostics → Drive → Motor Encoder. Verify MD 5022 value displays as 0.

Do not proceed with axis motion until this is resolved.

Consult motor nameplate and SSI encoder documentation for increments per revolution specification (typical range: 1024 to 262144 for SSI encoders). Cross-reference with drive parameter sheet.

Enter correct resolution value into MD 5022 via NCK Parameter Editor (Access Level 3 required). Use menu: Machine Data → Axis [axis] → Encoder → MD_ENC_ABS_RESOL_MOTOR.

Incorrect resolution will cause position feedback errors. Verify value matches encoder datasheet exactly.

Save machine data, perform warm restart (Ctrl+Shift+R or power cycle), and trigger axis homing cycle to re-validate encoder offset and resolution.

Physically verify the SSI encoder model number on the motor/spindle. Cross-check part number against maintenance logs or work order to confirm if encoder was recently replaced.

Retrieve encoder datasheet and note the resolution specification (increments per revolution or bits per turn for SSI protocol). Compare against current MD 5022 setting in machine data.

Ensure you have the correct datasheet for the installed encoder, not the previous model.

Update MD 5022 to the new encoder's resolution value. Use Service → Machine Data Editor → Axis [axis] → MD_ENC_ABS_RESOL_MOTOR. Set appropriate access level to allow modification.

Clear alarm via Reset, perform warm restart, and execute full axis referencing (G28.1 or manual homing) to re-establish absolute position zero with new encoder calibration.

Inspect SSI encoder cable (typically M12 connector or DB9) for visible damage, corrosion, or disconnection at motor and drive ends. Reseat connectors firmly with audible click.

Power down axis servo and drive before handling connectors.

Use oscilloscope or diagnostic cable tester to verify SSI signal lines (clock, data, parity) show valid waveforms at drive input. Expected SSI frequency typically 20–200 kHz depending on configuration.

If cable or connector is faulty, replace cable or connector assembly. Verify cable type matches SSI protocol (shielded twisted pair, characteristic impedance ~75Ω for SSI).

After cable repair, confirm MD 5022 is set to correct non-zero value, then power-cycle drive and re-trigger encoder initialization via NCK diagnostics.