Mitsubishi Electric FR-D700 Series Instruction Manual page 42

List of fault displays
Function Name
Overcurrent trip during
Overcurrent has occurred during acceleration.
acceleration
Overcurrent has occurred during constant speed
Overcurrent trip during
constant speed
operation.
Overcurrent has occurred during deceleration or
Overcurrent trip during
deceleration or stop at a stop.
Regenerative
overvoltage trip during Overvoltage has occurred during acceleration.
acceleration
Regenerative
Overvoltage has occurred during constant speed
overvoltage trip during
operation.
constant speed
Regenerative
Overvoltage has occurred during deceleration or
overvoltage trip during
at a stop.
deceleration or stop
Inverter overload trip
The electronic thermal relay function for inverter
(electronic thermal O/L
element protection has been activated.
relay function) 
Motor overload trip
The electronic thermal relay function for motor
(electronic thermal O/L
protection has been activated.
relay function) 
Heatsink overheat The heatsink has overheated.
One of the three phases on the inverter input side
has been lost. It may also appear if phase-to-
Input phase loss 
phase voltage of the three-phase power input
has become largely unbalanced.
The output frequency has dropped to 1Hz as a
Stall prevention stop result of deceleration due to the excess motor
load.
A fault has occurred in the brake circuit, such as
Brake transistor alarm
a brake transistor breakage. (In this case, the
detection
inverter must be powered off immediately.)
Output side earth
An earth (ground) fault has occurred on the
(ground) fault
inverter's output side (detected only at a start).
overcurrent at start
One of the three phases (U, V, W) on the
Output phase loss inverter's output side (load side) has been lost
during inverter operation.
38
Description
 Set the acceleration time longer. (Shorten the downward
 If "E.OC1" always appears at start, disconnect the motor once
 Check the wiring for output short circuit and ground fault.
 When the rated motor frequency is 50Hz, set the Pr. 3 Base
 Lower the stall prevention operation level.
 Activate the stall prevention operation and the fast-response
 For the operation with frequent regenerative driving, set the
 Keep the load stable.
 Check the wiring to avoid output short circuit or ground fault.
 Lower the stall prevention operation level.
 Activate the stall prevention operation and the fast-response
 Set the deceleration time longer.
 Check the wiring to avoid output short circuit or ground fault.
 Check if the mechanical brake is set to be activated too early.
 Lower the stall prevention operation level.
 Activate the stall prevention operation and the fast-response
 Set the acceleration time shorter.
 Use the regeneration avoidance function (Pr. 882, Pr. 883,
 Set the Pr.22 Stall prevention operation level correctly.
 Set Pr.154 Voltage reduction selection during stall prevention
 Keep the load stable.
 Use the regeneration avoidance function (Pr. 882, Pr. 883,
 Use the brake resistor, brake unit or power regeneration
 Set the Pr.22 Stall prevention operation level correctly.
 Set Pr.154 Voltage reduction selection during stall prevention
 Set the deceleration time longer. (Set the deceleration time
 Make the brake cycle longer.
 Use the regeneration avoidance function (Pr. 882, Pr. 883,
 Use the brake resistor, brake unit or power regeneration
 Set Pr.154 Voltage reduction selection during stall prevention
 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
 Reduce the load.
 Set the surrounding air temperature to within the specifications.
 Reduce the load.
 For a constant-torque motor, set the constant-torque motor in
 Set the stall prevention operation level accordingly.
 Set the surrounding air temperature to within the specifications.
 Clean the heatsink.
 Replace the cooling fan.
 Wire the cables properly.
 Repair a break portion in the cable.
 Check the Pr. 872 Input phase loss protection selection setting.
 Set Pr. 872 = "0" (without input phase loss protection) when
Reduce the load. (Check the Pr. 22 Stall prevention operation level
setting.)
Replace the inverter.
Remedy the ground fault portion.
 Wire the cables properly.
 If the motor capacity is smaller than the inverter capacity,
Corrective action
acceleration time in vertical lift application.)
and restart the inverter. If "E.OC1" still appears, the inverter
may be faulty. Contact your sales representative.
frequency to 50Hz.
current limit operation. (Pr.156)
base voltage (rated motor voltage, etc.) in Pr. 19 Base frequency
voltage.
current limit operation. (Pr.156)
current limit operation. (Pr.156)
Pr. 885, Pr. 886).
operation = "11".
Pr. 885, Pr. 886).
common converter (FR-CV) as required.
operation = "11".
which matches the moment of inertia of the load)
Pr. 885, Pr. 886).
common converter (FR-CV) as required.
operation = "11".
pattern of the using machine.
Pr. 71 Applied motor.
three-phase input voltage is largely unbalanced.
choose the inverter and motor capacities that match.
Display