MITSUBISHI ELECTRIC FR-S520E User Manual
Page 173
163
Errors (Alarms)
3
*1. Resetting the inverter initializes the internal thermal integratied data of the
electronic thermal relay function.
Operation Panel Indication
THM
FR-PU04
Motor Overload
Name
Motor overload shut-off (electronic thermal relay function) (* 1)
Description
The electronic thermal relay function in the inverter detects motor
overheat due to overload or reduced cooling capability during low-
speed operation to stop the inverter output. When a multi-pole
motor or two or more motors are run, provide a thermal relay on
the output side of the inverter.
Protection from burning due to motor temperature rise.
Check point
Check the motor for use under overload.
Corrective action
• Reduce the load weight.
• For a constant-torque motor, set the constant-torque motor in Pr.
71 "applied motor".
Operation Panel Indication
THT
FR-PU04
Inv. Overload
Name
Inverter overload shut-off (electronic thermal relay function) (* 1)
Description
If a current of more than 150% of the rated output current flows
and overcurrent shut-off does not occur (150% or less), inverse-
time characteristics cause the electronic thermal relay function to
be activated to stop the inverter output in order to protect the
output transistors.
Output transistor protection from overheat
Check point
Check the motor for use under overload.
Corrective action
Reduce the load weight.
Operation Panel Indication
FIN
FR-PU04
H/Sink O/Temp
Name
Fin overheat
Description
If the heatsink overheats, the temperature sensor is actuated to
stop the inverter output.
Check point
• Check for too high ambient temperature.
• Check for heatsink clogging.
Corrective action
Set the ambient temperature to within the specifications.
Operation Panel Indication
BE
FR-PU04
Br. Cct. Fault
Name
Brake transistor alarm detection (Available for the FR-S520E-0.4K
to 3.7K only.)
Description
This function stops the inverter output if an alarm occurs in the
brake circuit, e.g. damaged brake transistors.
In this case, the inverter must be powered off immediately.
Check point
• Reduce the load inertia.
• Check that the frequency of using the brake is proper.
• Check that the brake resistor selected is correct.
Corrective action
Replace the inverter.