Mitsubishi Electric F700 Instruction Manual page 251

Operation Panel
Indication
Name
Input phase failure
This alarm is output when function valid setting (=1) is set in Pr. 872 Input phase failure protection selection and
Description
one phase of the three phase power input opens. (Refer to
Check point
Check for a break in the cable for the three-phase power supply input.
· Wire the cables properly.
Corrective action
· Repair a brake portion in the cable.
· Check the Pr. 872 Input phase failure protection selection setting.
Operation Panel
Indication
Name
Stall prevention
If the frequency has fallen to 0.5Hz by stall prevention operation and remains for 3s, an alarm (E.OLT)
Description
appears to shutoff the inverter output. OL appears while stall prevention is being activated.
Check point
· Check the motor for use under overload. (Refer to
Corrective action · Reduce the load weight.
Operation Panel
Indication
Name
Output side earth (ground) fault overcurrent
This function stops the inverter output if an earth (ground) fault overcurrent flows due to an earth
Description
(ground) fault that occurred on the inverter's output (load) side.
Check point Check for an earth (ground) fault in the motor and connection cable.
Corrective action
Remedy the earth (ground) fault portion.
Operation Panel
Indication
Name Output phase failure
This function stops the inverter output if one of the three phases (U, V, W) on the inverter's output side
Description
(load side) opens.
· Check the wiring (Check that the motor is normal.)
Check point
· Check that the capacity of the motor used is not smaller than that of the inverter.
· Wire the cables properly.
Corrective action
· Check the Pr. 251 Output phase failure protection selection setting.
Operation Panel
Indication
Name External thermal relay operation
If the external thermal relay provided for motor overheat protection, or the internally mounted
Description
temperature relay in the motor, etc. switches on (contacts open), the inverter output is stopped.
· Check for motor overheating.
Check point
· Check that the value of 7 (OH signal) is set correctly in any of Pr. 178 to Pr. 189 (input terminal function
· Reduce the load and operating duty.
Corrective action
· Even if the relay contacts are reset automatically, the inverter will not restart unless it is reset.
*2 Functions only when any of Pr. 178 to Pr. 189 (input terminal function selection) is set to OH.
Operation Panel
Indication
Name
PTC thermistor operation
Appears when the motor overheat status is detected for 10s or more by the external PTC thermistor
Description
input connected to the terminal AU.
· Check the connection between the PTC thermistor switch and thermal relay protector.
· Check the motor for operation under overload.
Check point
· Is valid setting ( = 63) selected in Pr. 184 AU terminal function selection ? (Refer to
Corrective action
Reduce the load weight.
E.ILF
E.OLT
E.GF
E.LF
E.OHT
selection).
E.PTC
Causes and corrective actions
FR-PU04 Fault 14
FR-PU07 Input phase loss
page 135.)
FR-PU04
Stll Prev STP ( OL shown during stall
prevention operation)
FR-PU07
page 74.)
FR-PU04
Ground Fault
FR-PU07

FR-PU04
FR-PU07 E. LF
FR-PU04
OH Fault
FR-PU07
*2
FR-PU04 Fault 14
FR-PU07 PTC activated
5
page 96, 101.)
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