KEB COMBIVERT F5 Reference Manual page 280

Diagnostics and Troubleshooting
Error/Message Alt. /
(NUM)
Error Overheat EOH
Power Module (8)
280
*Additional information at end of section
Description Cause/Solution/Troubleshoot
The heat sink The heatsink temperature can be viewed in Diagnostics
temperature Screen #7 or DG37. The overheat limit is 90 degrees
rises above the Celsius for most drives (See Technical Data for units
permissible limit. 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
Verify operation of fans.
The fans are thermostatically controlled to come
on at about 45 degrees Celsius. To turn all fans
on high, LX06 Function Test can be set to Fans
On.
Make sure fans are not clogged.
Increase airflow around inverter or add cabinet fans.
Faulty temperature sensor.
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 diagnostics seems
unreasonably high for a heatsink cool to the touch,
then the heatsink temperature sensor may be faulty
and would need to be repaired by KEB.