Mitsubishi Electric FR-E700 Instruction Manual page 539

Troubleshooting
Operation panel
indication
Name
Description
Check point
Corrective action
Resetting the inverter initializes the internal thermal integrated data of the electronic thermal
relay function.
Operation panel
indication
Name
Description
Check point
Corrective action
Resetting the inverter initializes the internal thermal integrated data of the electronic thermal
relay function.
FR-E700 SC EC/ENE
E.THT
Inverter overload shut-off (electronic thermal relay function)
If the temperature of the output transistor element exceeds the protection level under the condi-
tion that a current not less than the rated inverter current flows and overcurrent trip does not
occur (230% or less), the electronic thermal relay activates to stop the inverter output. (Overload
capacity 150% for 60 s, 200% for 3s)
Check that acceleration/deceleration time is not too short.
Check that torque boost setting is not too large (small).
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 ambient temperature.
Increase acceleration/deceleration time.
Adjust the torque boost setting.
Set the load pattern selection setting according to the load pattern of the using machine.
Reduce the load weight.
Set the ambient temperature to within the specifications.
E.THM
Motor overload shut-off (electronic thermal relay function)
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 I²t value reaches 85% of the Pr. 9 "Electronic thermal O/L relay" setting and the protec-
tion circuit is activated to stop the inverter output when the I²t 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 ther-
mal relay function.
1) Check the motor for use under overload.
2) Check that the setting of Pr. 71 "Applied motor" for motor selection is correct.
(Refer to section 6.8.2.)
3) Check that the setting of Pr. 71 "Applied motor" for motor selection is correct.
(Refer to section 6.3.5.)
1) Reduce the load weight.
2) For a constant-torque motor, set the constant-torque motor in Pr. 71 "Applied motor".
3) Check that stall prevention operation setting is correct. (Refer to section 6.3.5.)
Causes and corrective actions
FR-PU04
Inv. Overload
FR-PU07
FR-PU04
Motor Overload
FR-PU07
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