10203

Check the HMI diagnostic screen to identify which specific axes are missing reference point status (typically indicated by red or unmarked indicators next to axis names).

Select JOG mode on the machine control panel and verify that the machine area is clear of obstructions and personnel before proceeding.

Ensure all safety guards are closed and emergency stop is released before attempting reference point approach.

Execute the reference point approach by pressing the REF button or selecting 'Reference Point' function, then activate each axis individually or use 'All Axes' function to home all axes simultaneously.

Monitor axis movement carefully during homing. Be ready to press emergency stop if unexpected motion occurs.

Verify all axes show green reference point indicators on the HMI, then attempt NC program start again in AUTO mode.

Access the alarm history (Diagnostics > Alarms) and review any preceding alarms related to position monitoring, encoder signals, or servo errors that may have caused reference point loss.

Check encoder connections and cable integrity for the affected axis. Verify encoder signals in Diagnostics > Drive > Encoder menu for proper square wave patterns and lack of error flags.

Do not disconnect encoder cables while control power is on as this may damage encoder electronics.

If encoder signals are valid, acknowledge all alarms, then perform reference point approach for all axes following the standard homing procedure.

If reference point is repeatedly lost, check machine data MD30200 (reference point monitoring) and MD36300 (position monitoring) settings, and inspect mechanical components for binding or excessive friction on the affected axis.

Navigate to Commissioning mode (access level: service/manufacturer) and check MD34100 $MA_REFP_CAM_IS_ACTIVE for each axis to ensure reference point switches are properly enabled.

Changes to machine data require manufacturer authorization and improper settings can cause machine damage or safety hazards.

Verify MD30240 $MA_ENC_REFP_STATE to confirm the axis is configured to require reference point before NC start (value should be 0 for standard operation).

Check for any active NC program commands such as G710 or DISPLOF that may affect reference point status, and ensure proper program structure with G74X commands as required.

Perform a controlled power cycle of the NCU, then execute complete reference point approach for all axes and verify alarm is cleared before production restart.

Coordinate power cycle with production schedule as all NC programs and offsets in volatile memory may be lost if not backed up.