20094

Check the Diagnostics menu (OEM > Diagnosis > Axes/Spindles) and verify the current axis state in the NCK. Look for 'Pulse Enable' status and cross-reference with MD20100 (ENABLE_AXIS_AFTER_RESTART) and MD20101 (ENABLE_AXIS_DURING_OPERATION).

Inspect the safety circuit and servo amplifier Enable Group signals. Verify no fault bits are set in the CNC status display. Check for tripped emergency stops, thermal overloads, or servo amp error codes (consult drive manufacturer documentation).

Do NOT attempt manual axis motion until enable signals are restored and fault conditions cleared.

Reset the system: Clear any active alarms via Reset (Ctrl+Reset), then power-cycle the servo drives and verify Enable Group signal continuity using a multimeter on the control cabinet terminals if hardware interlocks are suspected.

Confirm pulse enable restoration by monitoring the NCK Diagnostics > Servo/Spindle status until the axis shows 'Ready' state before restarting the program.

Access the PLC program via Siemens STEP 7 or via the CNC's PLC menu (Program > PLC > Monitor). Check for any conditional logic that disables DB21.DBX (Channel Ready) or DB21.DBX (Axis Ready) outputs during the active cycle.

Review the current PLC cycle state: In the CNC Diagnosis > PLC menu, confirm the status of system data bits controlling axis enablement. Cross-reference MD20110 (ALARM_REACTION_CHAN_NOREADY) to understand the configured reaction (typically 0=continue, 1=abort, 2=stop with ramp).

Check the PLC program for unintended transitions: Review program logic for unsafe states, mode-switch commands, or DRY-RUN / TEACH mode activations that may suppress axis ready signals. Verify no hardcoded disable logic exists for the target axis.

Restore PLC acknowledgment by re-enabling the channel/axis ready outputs in the PLC, or modify MD20110 to a less critical alarm reaction if the withdrawal is intentional (requires approval from machine builder).

Check the Alarm History: Review recent alarms in the CNC menu (Diagnosis > Alarm List). Identify any preceding faults (thermal, drive errors, limit switches) that may have triggered the NOT READY state. Address root cause alarms first.

Verify the current operating mode and axis state: Check OEM menu > Machine State and confirm the mode selector switch is in AUTO (not MANUAL/JOG). Ensure no active limits (software/hardware) are blocking the axis. Check MD20050 (AXIS_ENABLE_DELAY) and MD20060 (AXIS_DISABLE_DELAY) timings.

Manually reset the axis enable state by cycling the main power OFF for 10 seconds, then ON. This clears latched NOT READY flags in the NCK axis state machine.

Ensure all personnel are clear of the machine before power cycling.