Mitsubishi Electronics FR-V500 OH Fault, Stll Prev STP OL shown during stall, Option Fault

Errors (Alarms)

Operation Panel	E.OHT	FR-PU04V	OH Fault
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. If
	the relay contacts are reset automatically, the inverter will not restart unless it is reset.
Check point	• Check for motor overheating.
Corrective action	Reduce the load and operating duty.

Operation Panel	E.OLT	FR-PU04V	Stll Prev STP (OL shown during stall
Indication			prevention operation)
Name	Motor overload
	For V/F control, the stall prevention function is activated if the current flow in the motor exceeds
	150% (factory setting) of the inverter rated current, an alarm stop is made if the status that the
	output frequency is lowered at 0Hz persists for 3 seconds.
Description	For speed/position control, if the torque restriction is activated under high load, the motor stalls to
	the speed less than the low speed detection (Pr. 865) value, and an alarm stop is made if the status
	that the output torque is more than the OLT level setting (Pr. 874) value persists for 3 seconds.
	This function is not activated for torque control.
	• Check the motor for use under overload.
Check point	• Check that the low speed detection (Pr. 865) and OLT level setting (Pr. 874) values are correct.
	(Check the stall prevention operation level (Pr. 22) setting if V/F control is exercised.)
	• Reduce the load weight.
Corrective action	• Change the low speed detection (Pr. 865) and OLT level setting (Pr. 874) values.
	(Check the stall prevention operation level (Pr. 22) setting if V/F control is exercised.)
Operation Panel	E.OPT	FR-PU04V	Option Fault
Indication
Name	Option alarm
	Stops the inverter output when two or more communication options are mounted. (*5)
Description	When the high power factor converter (FR-HC) or power regeneration common converter (FR-CV)
	is connected, this alarm appears if an AC power supply is connected to the R, S, T terminals
	accidentally.
	• Check that the number of communication options mounted is one.
Check point	• When the high power factor converter (FR-HC) or power regeneration common converter (FR-
	CV) is connected, check that an AC power supply is not connected to the R, S, T terminals.
	• When the parameter set is for the option use, the option is not fitted nor connected securely.
	• Mount only one communication option.
	• Check the Pr. 30 setting and wiring.
Corrective action	• Check the Pr. 419 and Pr. 804 settings.
	• When the high power factor converter (FR-HC) or power regeneration common converter (FR-
	CV) is connected, connecting an AC power supply to the R, S, T terminals may damage the
	inverter. Please contact your sales representative.

*5:The FR-A5NR (relay output/co(Check the stall prevention operation level (Pr. 22) setting if V/F control is exer-

cised.)mputer link) allows one more communication option to be fitted. In this case, only relay output is usable and computer link is unusable.

Operation Panel	E.OP1 to	to	FR-PU04V	Option slot alarm 1 to 3
Indication	OP3
Name	Option slot alarm (1 to 3 indicate the option slot numbers.)
	Stops the inverter output if a functional alarm (e.g. communication line error of the communication
Description	option or contact fault of the plug-in option other than the communication option) occurs in the plug-
	in option fitted to the corresponding slot.
	• Check for a wrong option function setting and operation.
	• Check that the plug-in option is plugged into the connector securely.
Check point	• Check for an open communication cable.
	• Check that the termination resistor is fitted properly.
	• Check that the option card is normal.
Corrective action	• Check the option function setting, etc.
	• Connect the plug-in option securely.

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