250-1397

Check Emergency Stop Status

Verify all emergency stop buttons are released and check the status display in the TNC control for any active stop conditions.

Ensure machine safety before releasing any emergency stops

Clear Alarm and Reset Reference

Press the CE key to clear the alarm, then navigate to Manual Operation mode and restart the reference run using the REF key for the affected axis.

Check machine parameter MP1010 to verify reference run sequence settings

Monitor Reference Run Completion

Observe the axis movement during reference run to ensure it completes without interruption and reaches the reference mark successfully.

Check Limit Switch Status

Navigate to the diagnostic screen (CTRL + DIAG) and check the status of limit switches for the affected axis in the digital inputs display.

Machine parameters MP1020-MP1029 define limit switch assignments

Manually Move Axis Away from Limit

Use the handwheel or manual jog keys to carefully move the axis away from the activated limit switch position.

Move slowly and monitor for mechanical obstructions

Verify Reference Run Direction

Check machine parameter MP1030 (reference direction) to ensure the axis is homing in the correct direction away from limit switches.

Restart Reference Sequence

Clear the alarm and initiate a new reference run, monitoring that the axis moves in the proper direction toward the reference mark.

Check Encoder Diagnostics

Access the encoder diagnostic screen through CTRL + DIAG and verify the encoder signals and reference mark detection for the affected axis.

Look for consistent sine/cosine signals and proper reference mark pulse

Inspect Encoder Connections

Check the encoder cable connections at both the motor and drive amplifier, ensuring secure connections and no visible damage to cables.

Verify Machine Parameters

Check MP6010-MP6019 (encoder monitoring parameters) and MP1040 (reference mark search speed) to ensure proper encoder configuration.

Test Reference Mark Detection

Manually jog the axis slowly across the reference mark area while monitoring the encoder diagnostics to verify reference mark signal detection.

Inspect Axis Mechanically

Visually inspect the axis travel path for chips, tooling, fixtures, or other obstructions that could prevent free movement.

Ensure spindle is stopped and machine is in safe state before inspection

Check Servo Drive Status

Monitor the servo drive LEDs and check for following error or overload conditions in the drive diagnostic display.

Machine parameter MP1050 sets the maximum following error threshold

Test Manual Movement

Attempt to manually jog the axis at low feed rate to identify any binding or excessive resistance in the mechanical system.

Clear Obstruction and Retry

Remove any identified obstructions, ensure proper lubrication, and restart the reference run sequence.

Check Drive Status LEDs

Examine the servo drive amplifier status LEDs for fault indications (typically red LED patterns) and note any error codes displayed.

Consult the drive manufacturer's manual for specific LED fault code meanings

Verify Power Supply Voltages

Check the main power supply voltages to the servo drives and ensure stable 24VDC control voltage is present.

Reset Drive Amplifier

Power cycle the servo drive or use the drive reset function through the TNC diagnostic menu to clear any latched fault conditions.

Monitor Drive Parameters

Check drive temperature, current levels, and other operational parameters to identify potential issues before restarting reference run.