22002

Check software travel limits

Navigate to HMI → Commissioning → Machine → Axis → Travel Range and verify MD36100 $MA_POS_LIMIT_PLUS values are correctly set below hardware limit positions.

Leave at least 2-5mm safety margin between software limits and hardware switches

Verify working area settings

Check active G25/G26 working area limitations in HMI → Program → Current Values → G Functions and ensure they don't exceed MD36100 values.

Never set software limits beyond hardware switch positions

Reset and test movement

Clear alarm with RESET key, manually jog axis in negative direction using HMI → Machine → Manual → JOG mode until clear of limit switch.

Use incremental jog mode (INC) with small steps initially

Recalibrate reference point

Perform reference point approach via HMI → Machine → Reference Point to re-establish coordinate system if needed.

Check limit switch status

Navigate to HMI → Diagnostics → PLC → Inputs/Outputs and monitor the hardware limit input signal (typically DB31.DBX0.x for axis-specific HWLS+) while manually actuating switch.

Signal should toggle cleanly between 0 and 1 when switch is actuated

Verify switch wiring

Check electrical connections at limit switch and drive module X122/X132 terminals, verify 24VDC supply and proper NC/NO configuration per machine data MD30240 $MA_SAFE_POS_LIMIT.

Power down machine before checking electrical connections

Test switch mechanically

Manually actuate limit switch and verify proper mechanical operation - should have distinct click and spring return action.

Replace switch if contacts are pitted or mechanism feels loose

Temporary bypass for testing

If switch confirmed faulty, temporarily set MD30240 $MA_SAFE_POS_LIMIT bit for affected axis to 0 to disable hardware monitoring while replacing switch.

Only bypass temporarily - machine safety is compromised without hardware limits

Verify limit switch polarity

Check MD30240 $MA_SAFE_POS_LIMIT bit settings match actual switch wiring (NC vs NO configuration) in HMI → Commissioning → Machine → Axis → Monitoring.

Bit=1 for NO switches, Bit=0 for NC switches

Check axis direction configuration

Verify MD30300 $MA_IS_ROT_AX and MD30310 $MA_ROT_IS_MODULO settings are correct for linear vs rotary axes, and MD32000 $MA_DISPLAY_IS_METRIC matches machine units.

Validate coordinate system

Check MD34100 $MA_REFP_SET_POS reference point offset values and ensure coordinate system orientation matches physical machine layout.

Incorrect reference point settings can cause coordinate system inversion

Perform axis commissioning check

Run commissioning function HMI → Commissioning → Axis → Test → Limit Switch Test to verify all limit switches respond correctly to axis movement.

Inspect axis travel path

Visually examine entire axis travel range for obstructions, debris, damaged way covers, or improperly clamped workpieces that could block movement.

Ensure machine is powered down and locked out before manual inspection

Check for mechanical binding

Manually move axis (with drives disabled) to feel for binding, excessive friction, or mechanical resistance that could prevent proper deceleration.

Movement should be smooth and consistent throughout travel range

Verify collision detection settings

Check MD36650 $MA_COLLISION_TOL and related collision monitoring parameters in HMI → Commissioning → Machine → Axis → Monitoring to ensure proper sensitivity.

Collision detection should trigger before reaching hardware limits

Clear obstruction and test

Remove any identified obstructions, clear alarm, and perform slow manual jog test to verify normal axis operation before resuming automatic mode.

Check drive status

Navigate to HMI → Diagnostics → Drive → Status and examine drive fault history and current status for axis-specific drive module.

Look for preceding alarms like following errors, encoder faults, or drive overloads

Verify encoder feedback

Check encoder signals in HMI → Diagnostics → Drive → Encoder and verify position feedback is stable and tracking properly during manual movement.

Intermittent encoder signals can cause sudden position jumps

Test following error limits

Review MD36410 $MA_CONTOUR_TOL and MD36400 $MA_POS_TOL settings, perform slow jog movements while monitoring actual vs commanded position in real-time diagnostics.

Following errors should remain well within tolerance during normal movement

Drive parameter verification

Use STARTER software to verify drive parameters match motor specifications and perform drive optimization if position control appears unstable.