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Check Overload Status

Navigate to CURRENT COMMANDS > DIAGNOSTICS > INPUTS and verify conveyor overload input status. Look for overload relay physical position on motor starter.

Ensure main power is locked out before accessing electrical panels

Clear Physical Obstruction

Manually inspect conveyor chain/belt for chip jams, broken links, or foreign objects. Remove accumulated chips from conveyor housing and discharge chute.

Use compressed air to blow out packed chips from tight spaces

Reset Overload and Test

Press overload relay reset button on motor starter. Clear alarm with RESET key and test conveyor operation through CURRENT COMMANDS > COOLANT/CHIP CONVEYOR menu.

Monitor motor current draw during startup - should be consistent with nameplate values

Verify Contactor Operation

With power off, manually check contactor main and auxiliary contact alignment. Navigate to CURRENT COMMANDS > DIAGNOSTICS > INPUTS to monitor conveyor run feedback signal.

Use proper lockout/tagout procedures before electrical work

Test Contact Continuity

Using multimeter, test auxiliary contact continuity with contactor energized and de-energized. Check wiring connections at terminal blocks for looseness or corrosion.

Auxiliary contacts often fail before main contacts due to lower current rating

Replace or Adjust Contacts

Replace faulty auxiliary contact block or adjust contact alignment per manufacturer specifications. Verify proper feedback signal in NGC diagnostics before returning to service.

Keep spare auxiliary contact blocks in maintenance inventory

Check Control Circuit Fuses

Locate conveyor control circuit fuses in main electrical panel. Test fuse continuity and check for proper voltage at motor starter coil terminals.

Verify proper voltage rating before fuse replacement

Inspect Wiring Connections

Check all terminal connections from NGC I/O cards to motor starter, including control voltage, start signal, and feedback wiring. Look for loose, corroded, or damaged connections.

Use thermal imaging camera to identify hot spots indicating loose connections

Verify I/O Card Function

Test NGC output card function by monitoring output status in CURRENT COMMANDS > DIAGNOSTICS > OUTPUTS while commanding conveyor on/off. Check input card for proper feedback signal reception.

Swap I/O cards with known good channels to isolate card failures

Test Motor Isolation

Disconnect motor from conveyor drive mechanism and attempt manual rotation. Check for bearing roughness, binding, or excessive play in motor shaft.

Ensure motor is electrically isolated before mechanical testing

Measure Motor Parameters

Using megohmmeter, test motor winding insulation resistance. Measure winding resistance and compare to motor nameplate specifications or previous readings.

Document baseline motor parameters when new for future comparison

Evaluate Motor Replacement

If motor tests indicate failure, source replacement motor with identical specifications. Update maintenance records and consider upgrading to more efficient motor if available.

Consider keeping rebuilt spare motor in inventory for critical production machines

Review Conveyor Parameters

Access SETTING > PARAMETERS and review conveyor-related parameters including I/O assignments, timing delays, and fault detection settings. Compare with machine documentation.

Always backup parameters before making changes

Verify I/O Configuration

Check parameter settings for conveyor start output and run feedback input assignments. Ensure proper signal polarity and timing parameters are configured correctly.

Incorrect I/O assignments can damage equipment or create safety hazards

Test Parameter Changes

After parameter corrections, test conveyor operation through manual commands and automatic cycle. Monitor system response and verify alarm condition is resolved.

Document all parameter changes in machine maintenance log