Mitsubishi Electric FR-CS84-012 Instruction Manual page 218

Operation panel
E.OLT
indication
Stall prevention stop
Name
If the output frequency has fallen to 1 Hz by stall prevention operation and remains for 3 seconds, a fault (E.OLT)
Description
appears and the inverter is shut off. OLC appears while stall prevention is being activated.
• Check if the motor is not used under overload.
Check point
• Reduce the load.
• Change the Pr.22 setting.
Corrective action
• Also check that the stall prevention (overcurrent) warning (OLC) or the stall prevention (overvoltage) warning
(OLV) countermeasure is taken.
Operation panel
indication
Output side earth (ground) fault overcurrent
Name
The inverter output is shut off if an earth (ground) fault overcurrent flows due to an earth (ground) fault that
occurred on the inverter's output side (load side). Whether the protective function is used or not is set with Pr.249
Description
Earth (ground) fault detection at start.
Check for a ground fault in the motor and connection cable.
Check point
• Remedy the earth (ground) fault portion.
Corrective action
• Check the Pr.249 setting.
Operation panel
indication
Output phase loss
Name
The inverter output is shut off if one of the three phases (U, V, W) on the inverter's output side (load side) is lost.
Description
Whether the protective function is used or not is set with Pr.251 Output phase loss protection selection.
• Check the wiring. (Check that the motor is operating normally.)
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 setting.
Operation panel
E.OHT
indication
External thermal relay operation
Name
The inverter output is shut off if the external thermal relay provided for motor overheat protection or the internally
mounted thermal relay in the motor, etc. switches ON (contacts open). This function is available when "7" (OH
Description
signal) is set in any of Pr.178 to Pr.182 (input terminal function selection). This protective function is not
available in the initial status. (OH signal is not assigned.)
• Check for motor overheating.
• Check that the value "7" (OH signal) is set correctly to any of Pr.178 to Pr.182 (input terminal function
Check point
selection).
• Reduce the load and operation duty.
Corrective action
• Even if the relay contacts are reset automatically, the inverter will not restart unless it is reset.
Operation panel
indication
E.PE2
Parameter storage device fault
Name
The inverter output is shut off if a fault occurs in the stored parameters. (EEPROM failure)
Description
Check for too many number of parameter write times.
Check point
Contact your sales representative.
When performing parameter writing frequently for communication purposes, set "1" in Pr.342 Communication
Corrective action
EEPROM write selection to enable RAM write. Note that writing to RAM goes back to the initial status at power
OFF.
E.GF
E.LF
E.PE
FR-LU08 indication Stall Prev STP
FR-LU08 indication Ground Fault
FR-LU08 indication Output phase loss
FR-LU08 indication Ext TH relay oper
Corrupt Memory
FR-LU08 indication
PR storage alarm
6. PROTECTIVE FUNCTIONS
6.5 Causes and corrective actions
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