Mitsubishi FREQROL-E700

App.2-4
Function name Description Corrective action Display
Major
fault
Regenerative
overvoltage
trip during
constant
speed
Overvoltage has occurred
during constant speed
operation.
• Keep the load stable.
• Use the regeneration avoidance function (Pr. 882,
Pr. 883, Pr.885, Pr.886).
• Use the brake resistor, brake unit or power
regeneration common converter (FR-CV) as required.
• Set the Pr. 22 Stall prevention operation level correctly.
Regenerative
overvoltage
trip during
deceleration
or stop
Overvoltage has occurred
during deceleration or at a
stop.
• Set the deceleration time longer. (Set the deceleration
time which matches the moment of inertia of the load.)
• Make the brake cycle longer.
• Use the regeneration avoidance function (Pr. 882, Pr.
883, Pr.885, Pr.886).
• Use the brake resistor, brake unit or power
regeneration common converter (FR-CV) as required.
Inverter
overload trip
(electronic
thermal O/L
relay function)*
1
The electronic thermal
relay function for inverter
element protection has
been activated.
• Set the acceleration/deceleration time longer.
• Adjust the Pr. 0 Torque boost setting.
• Set the Pr. 14 Load pattern selection setting according
to the load pattern of the using machine.
• Reduce the load.
• Set the surrounding air temperature to within the
specications.
Motor overload
trip
(electronic
thermal O/L
relay function)*
1
The electronic thermal relay
function for motor protection
has been activated.
• Reduce the load.
• For a constant-torque motor, set the constant-torque
motor in Pr. 71 Applied motor.
• Set the stall prevention operation level accordingly.
Heatsink
overheat
The heatsink has
overheated.
• Set the surrounding air temperature to within the
specications.
• Clean the heatsink.
• Replace the cooling fan.
Input phase
loss*
3
One of the three phases
on the inverter input side
has been lost. It may also
appear if phase-to-phase
voltage of the three-phase
power input has become
largely unbalanced.
• Wire the cables properly.
• Repair a break portion in the cable.
• Check the Pr. 872 Input phase loss protection selection
setting.
• Set Pr. 872 Input phase loss protection selection = "0"
(without input phase loss protection) when three-phase
input voltage is largely unbalanced.
Stall
prevention
stop
The output frequency has
dropped to 1Hz as a result
of deceleration due to the
excess motor load.
Reduce the load. (Check the Pr. 22 Stall prevention
operation level setting.)