Mitsubishi Electric FR-F700 Series Instruction Manual page 75

Causes and corrective actions
Operation Panel
Indication
Name
Description
Check point
Corrective action
Operation Panel
Indication
Name
Description
Check point
Corrective action
Operation Panel
Indication
Name
Description
Check point
Corrective action
Operation Panel
Indication
Name
Description
Check point
Corrective action
*4 Functions only when any of Pr. 178 to Pr. 189 (input terminal function selection) is set to OH.
Operation Panel
Indication
Name
Description
Check point
Corrective action
Operation Panel
Indication
Name
Description
Check point
Corrective action
70
E.OLT
Stall prevention
If the frequency has fallen to 0.5Hz by stall prevention operation and remains for 3s, an alarm
(E.OLT) appears to shutoff the inverter output. OL appears while stall prevention is being activated.
· Check the motor for use under overload. (Refer to the Instruction Manual (applied).)
· Reduce the load weight.
E.GF
Output side ground fault overcurrent protection
This function stops the inverter output if a ground fault overcurrent flows due to an ground fault that
occurred on the inverter's output (load) side.
Check for a ground fault in the motor and connection cable.
Remedy the ground fault portion.
E.LF
Output phase failure protection
This function stops the inverter output if one of the three phases (U, V, W) on the inverter's output
side (load side) opens.
· Check the wiring (Check that the motor is normal.)
· Check that the capacity of the motor used is not smaller than that of the inverter.
· Wire the cables properly.
· Check the Pr. 251 Output phase failure protection selection setting.
E.OHT
External thermal relay operation
If the external thermal relay provided for motor overheat protection, or the internally mounted
temperature relay in the motor, etc. switches on (contacts open), the inverter output is stopped.
· Check for motor overheating.
· Check that the value of 7 (OH signal) is set correctly in any of Pr. 178 to Pr. 189 (input terminal
function selection).
· Reduce the load and operating duty.
· Even if the relay contacts are reset automatically, the inverter will not restart unless it is reset.
E.PTC
PTC thermistor operation
Appears when the motor overheat status is detected for 10s or more by the external PTC
thermistor input connected to the terminal AU.
· Check the connection between the PTC thermistor switch and thermal protector.
· Check the motor for operation under overload.
· Is valid setting (=63) selected in Pr. 184 AU terminal function selection ? (Refer to the Instruction
Manual (applied).)
Reduce the load weight.
E.OPT
Option alarm
Appears when the AC power supply is connected to the terminal R/L1, S/L2, T/L3 accidentally
when a high power factor converter is connected.
· Check that the AC power supply is not connected to the terminal R/L1, S/L2, T/L3 when a high power
factor converter (FR-HC, MT-HC) or power regenerative common converter (FR-CV) is connected.
· Check the parameter (Pr. 30) setting and wiring.
· The inverter may be damaged if the AC power supply is connected to the terminal R/L1, S/L2, T/
L3 when a high power factor converter is connected. Please contact your sales representative.
Still Prev STP ( OL shown during stall
FR-PU04
prevention operation)
FR-PU04 Ground Fault

FR-PU04
FR-PU04 OH Fault
*4
FR-PU04 Fault 14
FR-PU04 Option Fault