SV0002

Power off the machine and manually check Y-axis movement. With the machine in emergency stop, attempt to hand-jog the Y-axis slide. Feel for binding, rough spots, or abnormal resistance throughout the entire travel range.

Ensure all power is off and amplifiers are discharged before manual axis movement

Inspect Y-axis ballscrew and way surfaces for crash damage, debris, or inadequate lubrication. Check coupling between motor and ballscrew for looseness or misalignment. Verify gibs are properly adjusted per machine OEM specifications.

Navigate to DIAGNOSIS > SERVO screen and monitor parameter 300 (Servo Load Meter) for Y-axis while jogging slowly. Values consistently above 60-70% indicate excessive mechanical load. Compare to X and Z axes for baseline.

Check diagnosis screen parameter 200 (Current Feedback) for Y-axis during motion. Excessive current spikes or sustained high current relative to commanded motion confirms overload condition. Record values for comparison after mechanical correction.

Navigate to SYSTEM > PARAM and verify Y-axis motor parameters: P1825 (CMX - max current), P1820 (motor type code), P1815 (motor serial encoder selection). Cross-reference against motor nameplate and amplifier specifications to ensure proper match.

Incorrect P1825 CMX settings can cause immediate motor damage if set too high

Check P2000-P2084 (Y-axis servo gain parameters). Verify P2020 (position loop gain), P2021 (velocity loop gain), and P2023 (time constant) are appropriate for the motor/load combination. Excessively high gains increase current draw and oscillation.

Review P2133 (Disturbing observer gain) and P2134 (Torque command acceleration filter). If recently modified or machine restored from backup, these advanced tuning parameters may be causing excessive torque commands during acceleration.

If parameters were recently changed or amplifier replaced, restore known-good parameter backup or reset to OEM default values. Execute Auto-Tuning function (MAINTENANCE > SERVO > AUTO TUNING for applicable systems) and test with light cutting loads.

Check Y-axis amplifier LED indicators. Solid red or flashing red patterns indicate amplifier fault detection. Consult amplifier model-specific LED chart (αi series: 2-digit codes, βi series: multi-color patterns) for specific fault codes.

With machine powered on but not moving, navigate to DIAGNOSIS > SERVO and check parameter 400 (Motor temperature) for Y-axis. Values consistently above 60-70°C at idle indicate motor bearing failure or inadequate motor cooling fan operation.

Perform motor insulation resistance test (megger test) on Y-axis motor with power disconnected at amplifier. Measure between windings U-V-W and between each phase and motor frame ground. Values below 10 MΩ indicate winding insulation breakdown requiring motor replacement.

Disconnect all motor power and encoder cables before performing megger test to prevent amplifier damage

Swap Y-axis amplifier with another axis (if same model) to determine if fault follows amplifier or remains with motor. If alarm transfers to different axis, replace amplifier. If alarm stays with Y-axis, replace motor and verify coupling alignment during installation.