231-C460

Check maximum speed parameter

Navigate to MOD > Machine Parameters > MP1410 (Maximum spindle speed) and verify the value matches motor specifications.

Compare with motor nameplate data - typical servo motors are rated 3000-6000 RPM

Review velocity loop gains

Check MP1020 (Velocity loop gain) and MP1030 (Velocity loop integration time). Reduce MP1020 by 20-30% if values seem excessive.

Always backup machine parameters before making changes

Verify position loop gain

Examine MP1040 (Position loop gain). High values can cause instability. Start with manufacturer recommended values and tune gradually.

Use TNC's built-in servo trace function to visualize loop response

Test with reduced gains

Temporarily reduce all servo gains by 50% and test axis movement to confirm stability before fine-tuning.

Reduced gains will affect positioning accuracy until properly tuned

Check encoder cable connections

Inspect encoder cable at motor and drive connections. Look for loose connections, damaged shielding, or cable wear at flex points.

Encoder cables should have 360-degree shield connection at both ends

Verify encoder supply voltage

Measure encoder supply voltage at motor connection (typically 5VDC ±5%). Check for voltage drops under load conditions.

Use proper ESD precautions when working with encoder electronics

Monitor encoder signals

Use TNC diagnostic screen MOD > Diagnosis > Encoder signals to check A/B quadrature signals and reference pulse integrity.

Signals should show clean square waves with 90-degree phase relationship

Test encoder mechanically

Manually rotate motor shaft and observe encoder count changes in TNC position display for smooth, consistent counting.

Ensure axis drives are disabled before manual rotation

Perform manual axis movement test

Use TNC manual mode to move axis at slow feed rates (10-50 mm/min) and listen for unusual noises or binding.

Compare movement smoothness between all axes to identify problematic axis

Check mechanical backlash

Use TNC's backlash measurement function or manually check for excessive play in ball screw and coupling connections.

Excessive backlash can cause servo hunting and instability

Inspect lubrication system

Verify proper lubrication of slideways and ball screws. Check automatic lubrication system operation and oil levels.

Insufficient lubrication is a common cause of binding and servo instability

Monitor following error

Check following error values in TNC diagnosis screens during movement. Excessive values indicate mechanical problems.

Following errors exceeding 0.1mm typically indicate mechanical issues

Check drive status LEDs

Examine servo drive front panel LEDs for error indicators. Consult drive manual for LED status interpretation.

Most Heidenhain-compatible drives have standardized LED error codes

Verify drive parameter settings

Compare drive internal parameters with motor nameplate data, especially motor rated current, voltage, and speed parameters.

Incorrect motor parameters can cause drive instability and damage

Test drive with different motor

If possible, swap motor connections with known good axis to isolate drive vs. motor issues.

Ensure motor parameters match before swapping connections

Check drive cooling and temperature

Verify drive cooling fans operation and check for overheating. Clean heat sinks if necessary.

Overheating drives often exhibit intermittent control problems

Verify motor nameplate data

Compare motor nameplate specifications with TNC parameters MP1410 (max speed) and related motor parameters.

Take photos of all motor nameplates for reference during parameter setup

Check gear ratio parameters

Verify MP1420 (gear ratio numerator) and MP1430 (gear ratio denominator) match actual mechanical gear ratios.

Incorrect gear ratios cause speed and position calculation errors

Validate encoder resolution settings

Confirm encoder lines per revolution parameter matches actual encoder specification (typically 1024, 2048, or 4096 lines).

Encoder resolution is usually marked on encoder nameplate or cable tag

Test calculated vs actual movement

Command a known distance movement and measure actual travel to verify parameter accuracy.

Incorrect parameters affect both speed monitoring and positioning accuracy