EOH fault in KEB COMBIVERT F5 Drive indicates an Overheat Power Module. This means the inverter’s heatsink temperature rose above the safe operating limit due to poor ventilation or fan failure.
Cause:
The heatsink temperature can be viewed in ru.38. The overheat limit is 90 degrees Celsius for most drives (see Technical Data for units 175HP and larger). Under normal operation, the heatsink temperature should usually be below 65 degrees Celsius.
Causes of inverter heatsink overheat include:
- Insufficient cooling or ambient temperature too high.
- Faulty temperature sensor.
Remedy:
- Verify operation of fans: The fans are thermostatically controlled to come on at about 45 degrees Celsius. To turn all fans on high, US.37 Function Test can be set to “Fans On”.
- Make sure fans are not clogged.
- Increase airflow around the inverter or add cabinet fans.
- Check sensor integrity: Power down the inverter or let it stand idle to allow for the heatsink temperature to cool. If the heatsink temperature read by the drive for diagnostics seems unreasonably high for a heatsink cool to the touch, the heatsink temperature sensor may be faulty and would need to be repaired by KEB.
