Mitsubishi Electric FR-D720-0.1K Instruction Manual page 263

Operation panel
E.THT
indication
Name
Inverter overload trip (electronic thermal O/L relay function)
If the temperature of the output transistor element exceeds the protection level under the condition that a current not
Description less than the rated inverter current flows and overcurrent trip does not occur (200% or less), the electronic thermal
relay activates to stop the inverter output. (Overload capacity 150% 60s, 200% 0.5s)
Check that acceleration/deceleration time is not too short.
Check that torque boost setting is not too large (small).
Check point Check that load pattern selection setting is appropriate for the load pattern of the using machine.
Check the motor for use under overload.
Check for too high surrounding air temperature.
Increase acceleration/deceleration time.
Adjust the torque boost setting.
Corrective action
Set the load pattern selection setting according to the load pattern of the using machine.
Reduce the load weight.
Set the surrounding air temperature to within the specifications.
Operation panel
E.THM
indication
Motor overload trip (electronic thermal O/L relay function) ∗1
Name
The electronic thermal relay function in the inverter detects motor overheat due to overload or reduced cooling
capability during constant-speed operation, and pre-alarm (TH display) is output when the integrated value reaches
85% of the Pr. 9 Electronic thermal O/L relay setting, and the protection circuit is activated to stop the inverter output
Description
when the integrated value reaches the specified value. When running a special motor such as a multi-pole motor or
multiple motors, provide a thermal relay on the inverter output side since such motor(s) cannot be protected by the
electronic thermal relay function.
Check the motor for use under overload.
Check point Check that the setting of Pr. 71 Applied motor for motor selection is correct. (Refer to page 104).
Check that stall prevention operation setting is correct.
Reduce the load weight.
Corrective action For a constant-torque motor, set the constant-torque motor in Pr. 71 Applied motor.
Check that stall prevention operation setting is correct. (Refer to page 80).
∗1
Resetting the inverter initializes the internal thermal integrated data of the electronic thermal relay function.
Operation panel
E.FIN
indication
Name Heatsink overheat
If the heatsink overheats, the temperature sensor is actuated and the inverter trips.
The FIN signal can be output when the temperature becomes approximately 85% of the heatsink overheat protection
Description
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, Pr. 192 or Pr. 197 (output terminal function selection). (Refer to page 120).
Check for too high surrounding air temperature.
Check for heatsink clogging.
Check point
Check that the cooling fan is not stopped (Check that
Set the surrounding air temperature to within the specifications.
Corrective action Clean the heatsink.
Replace the cooling fan.
Causes and corrective actions
FR-PU04
Inv. Overload
FR-PU07
FR-PU04
Motor Ovrload
FR-PU07
FR-PU04
H/Sink O/Temp
FR-PU07
is not displayed on the operation panel).
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