Mitsubishi Electronics FR-S500 FR-PU04, OV During Acc, Stedy Spd OV, OV During Dec, Errors Alarms

Errors (Alarms)

Operation Panel Indication	OV1		FR-PU04	OV During Acc
Name	Regenerative	overvoltage shut-off during		acceleration
	When the main circuit DC voltage in the inverter rises to or above
Description	the specified value due to excessive regenerative energy during
	acceleration, the protective circuit is activated to stop the inverter
	output. The circuit may also be activated by a surge voltage
	produced in the power supply system.
Check point	Check for too slow acceleration. (e.g. during downward
	acceleration in vertical lift load)
Corrective action	• Decrease the acceleration time.
	• Install a power factor improving reactor.

Operation Panel Indication	OV2		FR-PU04	Stedy Spd OV
Name	Regenerative	overvoltage shut-off during constant speed
	When the main circuit DC voltage in the inverter rises to or above
Description	the specified value due to excessive regenerative energy during
	constant speed, the protective circuit is activated to stop the inverter
	output. The circuit may also be activated by a surge voltage
	produced in the power supply system.
Check point	Check for sudden load change.
Corrective action	• Keep load stable.
	• Install a power factor improving reactor.

Operation Panel Indication	OV3		FR-PU04		OV During Dec
Name	Regenerative	overvoltage shut-off during		deceleration or stop
	When the main circuit DC voltage in the inverter rises to or above
Description	the specified value due to excessive regenerative energy during
	deceleration or stop, the protective circuit is activated to stop the
	inverter output. The circuit may also be activated by a surge
	voltage produced in the power supply system.
Check point	Check for sudden speed reduction.
	• Increase the deceleration time. (Set the deceleration time which
Corrective action	matches the moment of inertia of the load)
	• Decrease the braking duty.
	• Install a power factor improving reactor.

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