330-0027

Access Machine Parameters

Navigate to MOD function, enter machine parameters with MP7500 password, go to axis-specific parameters for the affected axis.

Always backup current parameters before making changes using the parameter export function

Verify Encoder Parameters

Check MP4110 (position encoder line count), MP4010 (speed encoder line count), and MP1020 (screw pitch) match actual hardware specifications.

Incorrect encoder parameters can cause severe positioning errors and potential crashes

Validate Gear Ratio Settings

Confirm MP1030 (gear ratio numerator) and MP1040 (gear ratio denominator) are correctly set for any gearing between motor and ballscrew.

Check Safety Parameters

Review CfgAxisSafety->positionDiffRef and CfgAxisSafety->positionDiffRun values in the configuration files to ensure appropriate tolerance settings.

Manual Backlash Test

Use TNC manual mode (MDI) to move axis in small increments (0.001mm) and observe position feedback consistency on the position display.

Ensure machine is properly referenced before performing manual movements

Inspect Mechanical Couplings

Check motor-to-ballscrew coupling for wear, looseness, or damage. Look for play between motor shaft and ballscrew input.

Use dial indicator on ballscrew while manually rotating motor shaft to measure coupling backlash

Evaluate Ballscrew Condition

Inspect ballscrew and nut assembly for wear, contamination, or damage that could cause position variation during direction changes.

Test with Backlash Compensation

Temporarily increase MP1050 (backlash compensation) value and test if alarm frequency decreases, indicating mechanical backlash issue.

Check Encoder Status

Access diagnostic screen via DIAG key, select encoder diagnostics to view position encoder signal quality and error counters.

Look for intermittent signal loss or amplitude variations in the encoder diagnostics

Inspect Linear Scale Installation

Verify linear scale mounting, reading head gap (typically 0.5-1.0mm), and cleanliness of scale surface and reading head.

Never touch linear scale surface with bare hands - use lint-free cloth and appropriate cleaner

Test Encoder Cables

Check encoder cable routing for damage, proper shielding connection, and secure connections at both encoder and TNC ends.

Monitor Position Values

Use TNC's position monitoring function to observe real-time position encoder values during slow axis movement for irregularities.

Monitor Speed Encoder Signals

Access servo diagnostics through DIAG menu to view speed encoder signal amplitude, frequency, and phase relationships.

Compare signal patterns between working and problematic axes to identify anomalies

Check Motor Encoder Connection

Inspect motor encoder cable connections, verify proper shielding, and test continuity of encoder power and signal lines.

Evaluate Motor Mechanical Condition

Listen for unusual motor bearing noise, check for excessive motor vibration, and verify smooth motor shaft rotation when uncoupled.

Test Encoder Functionality

Use oscilloscope to verify clean encoder A/B quadrature signals and proper index pulse if accessible at motor junction box.

Check Power Supply Stability

Monitor DC bus voltage and motor supply voltages in servo diagnostics for fluctuations or irregularities during axis movement.

Inspect Electrical Connections

Verify all power and signal connections are tight, properly torqued, and free from corrosion at servo drive and motor terminals.

Evaluate EMI Sources

Check for electromagnetic interference sources near encoder cables, ensure proper cable separation from power lines, and verify shielding integrity.

Temporary rerouting of encoder cables away from suspected EMI sources can help isolate interference issues