244
Causes and corrective actions
Operation panel
indication
E.ILF
FR-PU07 Input phase loss
Name
Input phase loss
Description
Drive unit trips when function valid setting (=1) is selected in Pr. 872 Input phase loss protection selection and one phase
of the three phase power input is lost. (Refer to page 128).
It may function if phase-to-phase voltage of the three-phase power input becomes largely unbalanced.
When the setting of Pr. 872 Input phase loss protection selection is the initial value (Pr. 872 ="0"), this warning does not
occur.
Check point
Check for a break in the cable for the three-phase power supply input.
Check that phase-to-phase voltage of the three-phase power input is not largely unbalanced.
Corrective action
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 three-phase input voltage is largely unbalanced.
Operation panel
indication
E.OLT
FR-PU07 Stll Prev STP
Name
Stall prevention stop
Description
If the rotation speed has fallen to 15r/min by stall prevention operation and remains for 3s, a fault (E.OLT) appears
and the drive unit trips. OL appears while stall prevention is being activated.
E.OLT may not occur if stall prevention (OL) is activated during output phase loss.
Check point
Check the motor for use under overload. (Refer to page 75).
Check that a motor is connected.
Corrective action
Reduce the load weight. (Check the Pr. 22 Stall prevention operation level setting.)
Check the connection of the motor.
Set the PM motor test operation. (Refer to page 69)
Operation Panel
Indication
E.SOT FR-PU07 Motor step out
Name
Loss of synchronism detection
Description
Stops the output when the operation is not synchronized.
Check point
Check that the PM motor is not driven overloaded.
Check if a start command is given to the drive unit while the PM motor is coasting.
Check if a motor other than the PM motor (S-PM series) is driven.
Corrective
action
Set the acceleration time longer.
Reduce the load.
Input a start command after the motor stops.
Drive the PM motor (S-PM series).
Operation panel
indication
E.BE FR-PU07 Br. Cct. Fault
Name
Brake transistor alarm detection
Description
When a brake transistor alarm has occurred due to the large regenerative energy from the motor etc., the brake
transistor alarm is detected and the drive unit trips.
In this case, the drive unit 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 drive unit.
Operation panel
indication
E.GF
FR-PU07 Ground Fault
Name
Output side earth (ground) fault overcurrent at start
Description
The drive unit trips if an earth (ground) fault overcurrent flows at start due to an earth (ground) fault that occurred on
the drive unit's output side (load side). Whether this protective function is used or not is set with Pr. 249 Earth (ground)
fault detection at start. When the setting of Pr. 249 Earth (ground) fault detection at start is the initial value (Pr. 249 ="0"),
this warning does not occur.
Check point
Check for a ground fault in the motor and connection cable.
Corrective action
Remedy the ground fault portion.
