230-04D6

Power down TNC system safely

Execute emergency stop, allow spindle to stop completely, then power off main disconnect. Wait 10 minutes for components to cool.

Never open electrical cabinet while system is energized

Inspect cabinet air filters

Remove filter pads from intake and exhaust vents on electrical cabinet. Check for dust, oil mist, or debris accumulation blocking airflow.

Use compressed air at 30 PSI maximum to clean filters - higher pressure can damage filter media

Clean or replace filter elements

Clean reusable filters with degreaser and compressed air, or install new filter pads. Ensure proper sealing when reinstalling to prevent bypass airflow.

Verify airflow restoration

Power up system and monitor cabinet temperature. Check that cooling fans are drawing air through clean filters with no obstruction.

Check fan operation status

Access MOD function, navigate to DIAGNOSIS menu, select HARDWARE INFO to view fan status and RPM readings for all cabinet cooling fans.

Fan RPM should typically be 2000-3000 RPM depending on model - significantly lower values indicate bearing wear

Perform visual fan inspection

With power off, manually rotate each fan blade assembly. Check for binding, excessive play in bearings, or damaged blades that reduce airflow efficiency.

Test fan electrical connections

Verify 24VDC supply voltage at fan connectors using multimeter. Check connector pins for corrosion or loose connections that cause intermittent operation.

Replace defective fan units

Install replacement fans with identical specifications (voltage, current, CFM rating). Ensure proper wire routing to prevent interference with cabinet doors.

Use only Heidenhain approved replacement fans to maintain UL/CE compliance

Measure cabinet ambient temperature

Use calibrated thermometer to check air temperature at cabinet intake vents. TNC specifications require ambient below 40°C (104°F) for proper operation.

Check temperature during hottest part of production day - afternoon shifts often see highest ambient temperatures

Evaluate cabinet location and ventilation

Ensure minimum 6-inch clearance around cabinet vents. Check that cabinet is not located near heat sources like furnaces, welding stations, or in direct sunlight.

Assess facility cooling requirements

Calculate heat load from all electrical cabinets and machinery. Verify HVAC system capacity meets total cooling requirements for the production area.

Implement additional cooling measures

Install auxiliary cooling fans, relocate cabinet to cooler area, or upgrade facility HVAC system to maintain proper ambient temperature range.

Access temperature monitoring data

Navigate to MOD > DIAGNOSIS > TEMPERATURE to view real-time temperature readings from all sensors in the TNC system including CC unit sensor values.

Compare sensor readings with infrared measurement

Use infrared thermometer to measure actual CC unit surface temperature and compare with TNC displayed values. Significant variance indicates sensor failure.

Measure at multiple points on CC heat sink - temperature should be relatively uniform across the surface

Check sensor wiring and connections

Inspect temperature sensor cable for damage, loose connections at terminal blocks, or corrosion that could cause erratic readings.

Replace temperature sensor assembly

Install new temperature sensor with proper thermal compound application. Verify correct sensor type and resistance values per Heidenhain specifications.

Sensor replacement requires partial disassembly of CC unit - contact Heidenhain service if unfamiliar with procedure

Monitor servo drive loading

Access MOD > DIAGNOSIS > SERVO to view real-time current consumption and power levels for all axis drives. Compare values to nameplate ratings.

Check both RMS and peak current values - sustained high currents indicate mechanical binding or improper servo tuning

Review servo parameter settings

Check machine parameters MP1020-MP1099 for servo tuning values. Verify current limits, velocity feedforward, and position loop gains are properly configured.

Inspect mechanical drive systems

Check for binding in linear guides, worn ball screws, or inadequate lubrication causing excessive servo loading and heat generation.

Optimize servo tuning parameters

Use Heidenhain servo optimization procedures to reduce unnecessary current consumption while maintaining positioning accuracy and dynamic performance.