230-041A

Access machine parameters

Press MOD key, enter access code, navigate to Machine Parameters > Axis-specific parameters > Select the affected axis

Document original parameter values before making any changes

Check MP1010 current value

Locate MP1010 (Maximum permissible position error) and note the current value in millimeters or degrees. Typical values range from 0.5mm to 2.0mm for linear axes depending on machine type

Compare this value against similar machines in your facility - consistent values indicate proper baseline

Monitor actual position error during operation

Navigate to Test > Position display or use MOD > Position menu to display real-time following error (Schleppfehler). Run typical part program and observe peak following error values

Peak following error should be 50-70% of MP1010 value during normal operation - if consistently higher, either MP1010 is too tight or servo tuning needs optimization

Adjust MP1010 if appropriate

If mechanical and encoder systems are verified good and peak following errors approach or exceed MP1010 during normal operation, incrementally increase MP1010 by 0.2-0.5mm. Test thoroughly and ensure position accuracy remains acceptable

Increasing MP1010 reduces protection against mechanical failures - only adjust after ruling out mechanical and servo tuning issues

Disable axis drive for manual test

Navigate to Test > Axis ON/OFF menu, deselect the affected axis to disable the drive. Acknowledge safety warnings and ensure machine is in safe state

Axis will be free to move under gravity or external forces when drive is disabled - secure heavy components

Manually check axis movement

Move the axis by hand through full travel range. Feel for tight spots, grinding, irregular resistance, or abnormal sounds. Movement should be smooth and consistent throughout entire travel

Note the specific position where binding occurs - this helps identify specific mechanical components (way covers, cable carriers, ballscrew sections)

Inspect mechanical components

Check ballscrew/linear motor for damage, verify way lubrication system operation, inspect cable carrier for binding, check coupling alignment, and verify preload adjustments on bearings and ballnut

Temperature variation can affect preload - check if alarm occurs after machine warmup indicating thermal expansion issues

Review axis load monitoring

Enable drive and navigate to Test > Drive diagnosis. Monitor motor current during slow programmed moves. Compare current values at different positions - significant variations indicate mechanical issues

Current should be relatively constant during constant velocity moves - spikes indicate mechanical resistance points

Record current servo parameters

Access Machine Parameters for affected axis and document current values: MP1310 (Kv factor/position loop gain), MP1320 (velocity feedforward), MP1330 (acceleration feedforward), and MP1340 (jerk filter time constant)

Take screenshots or write down all MP1300 series parameters - you'll need baseline values if tuning doesn't improve situation

Analyze following error characteristics

Run test program with various feed rates while monitoring position error in Position display menu. Note whether error is constant (indicates Kv too low), increases with acceleration (indicates accel feedforward too low), or oscillates (indicates overtuning)

Following error proportional to velocity indicates insufficient velocity feedforward MP1320 - following error during acceleration/deceleration indicates insufficient acceleration feedforward MP1330

Optimize Kv factor (MP1310)

If following error is consistently high during constant velocity, incrementally increase MP1310 by 10-15%. Test after each change. Typical values range from 0.5 to 2.5 depending on axis mass and drive configuration

Excessive Kv factor causes oscillation and instability - increase gradually and test thoroughly. Never exceed machine builder's maximum recommended value