Mitsubishi Electric FR-CC2-P, Instruction Manual

Page: 146 / 184

Causes and corrective actions
PROTECTIVE FUNCTIONS
145
6
 Alarm
The inverter output is not shut off when a protective function is activated. An alarm can also be output with a parameter
setting.
(Set "98" in
Pr.190 to Pr.195 (Output terminal function selection). (Refer to page 105 .)
 Fault
When a protective function activates, the inverter output is not shut off and a fault signal is output.

Resetting the converter unit initializes the internal cumulative heat value of the electronic thermal O/L relay function.
Operation panel
indication
FN
Name
Fan alarm
Description
FN appears on the operation panel when the cooling fan of the converter unit stops due to a fault or when the
speed decreases.
Check point
Check the cooling fan for a failure.
Corrective action
Check for fan failure. Contact your sales representative.
Operation panel
indication
E.OVT
Name
Overvoltage trip
Description
If the converter unit's internal main circuit DC voltage reaches or exceeds the specified value, the protective
circuit is activated to stop the inverter output. The circuit may also be activated by a surge voltage produced
in the power supply system.
Check point
• Check for sudden load change or excessive regeneration.
• Check for power fault.
Corrective action
• Keep the load stable.
• Check the power supply.
Operation panel
indication
E.THC
Name
Converter overload trip (electronic thermal relay function)

Description
For the protection of converter unit diode, the electronic thermal O/L relay is activated in inverse-time
characteristics against the converter unit input current to shut off the inverter output.
Check point
• Check the motor for the use under overload.
• Check that the capacity of the inverter used is not larger than that of the converter unit.
Corrective action
• Reduce the load.
• Check the configuration of the inverter and the converter unit again.
Operation panel
indication
E.FIN
Name
Heat sink overheat
Description
When the heat sink overheats, the temperature sensor activates, and the inverter output is stopped.
The FIN signal can be output when the temperature reaches approximately 85% of the heat sink overheat
protection operation temperature.
For the terminal used for the FIN signal output, assign the function by setting "26 (positive logic) or 126
(negative logic)" in any of
Pr.190 to Pr.195 (Output terminal function selection) . (Refer to page 105 .)
Check point
• Check for too high surrounding air temperature.
• Check for heat sink clogging.
• Check that the cooling fan is not stopped. (Check that FN is not displayed on the operation panel.)
Corrective action
• Set the surrounding air temperature to within the specifications.
• Clean the heat sink.
• Replace the cooling fan.