Toshiba VF-A7 ･ Raise rating of the inverter, ･ Reset the inverter, Stop,  Initial read-error

(Continued from the preceding page)

Indication	Contents	Expected causes	Countermeasures
		･ Input voltage abnormally varied.	･ Try to insert input reactor.
		1 Power capacity is 500 kVA or
		more.
		2 Power-factor improving
	Over-voltage	capacitor was turned on/off.
		3 Some unit using thyrister is
	during fixed	connected with the same	･ Install dynamic braking resistor.
	speed	power supply line.
		･ Motor falls into regeneration status
		because it is rotated fast
		exceeding inverter's output
		frequency by power of loaded
		side.
		･ Rapid acceleration is operated.	･ Extend acceleration time #1 .
		･ DC breaking rate is too high.	･ Decrease values of DC injection
	Inverter	･ V/f parameter is improperly set.	braking current  and DC
		･ Running motor is started during	injection braking time .
	overloaded	momentary power failure status	･ Check V/f parameter.
		or so.	･ Use (Auto-restart) and 
		･ Load is too heavy.	(Regenerative power ride-through control).
			･ Raise rating of the inverter.
		･ V/f parameter is improperly set.	･ Check V/f parameter.
	Motor	･ Motor is locked.	･ Check loading unit.
		･ Continuous operation in low	･ Reset  properly to motor's
	overloaded
		speed range.	overload reduction start-up
		･ Motor is operated with overload.	frequency.
		･ Rapid deceleration is operated.	･ Extend deceleration time #1 .
	Dynamic braking	･ Dynamic braking rate is too high.	･ Increase capacity (wattage) of
	resistor overload	･ Set over-voltage limit operation	dynamic braking resistor and reset
			the PBR capacity parameter .
		revel parameter  too small.	･ Increase the setting value of .
		･ Cooling fan is not actuated.	･ After cooling down inverter, reset it
		･ Ambient temperature is too high.	from failure and try to restart it.
			･ If cooling fan does not work in
	Overheat	･ Vent of cooling fan is shut.	operation, it needs replacement.
			･ Secure spaces in the periphery of the
		･ Some heat generating matter is	inverter.
		located nearby.	･ Don't locate any heat generating thing
		･ Internal thermistor of unit is	near the inverter.
		disconnected.	･ Make a service call.
	Emergency	･ Inverter is stopped by panel operation	･ Reset the inverter.
	stop	during automatic or remote operation.
	EEPROM error	･ Error occurs during writing data.	･Again turn on the inverter. If it is not
			reset, make a service call.
	Initial read-error	･ Something abnormal in internal data.	･ Make a service call.
	Initial read-error	･ Something abnormal in internal data.	･ Make a service call.
	Main RAM fault	･ Something abnormal in control RAM.	･ Make a service call.
	Main ROM fault	･ Something abnormal in control ROM.	･ Make a service call.
	CPU fault	･ Something abnormal in control CPU.	･ Make a service call.
	Interruption	･ Something abnormal occurred	･ Check communication units and their
	communication	during communication operation.	connections.
	fault
	Gate array	･ Main gate array is abnormal.	･ Make a service call.
	fault
	Output current	･ Main output current detector is	･ Make a service call.
	detector error	abnormal.
	Optional unit	･ Something abnormal occurred in	･ Check connection of optional
		some optional unit (including	board(s).
	fault	abnormal communication [optional	･ Refer to instructions of options
		add-on cassettes]).	concerned.
	Flush memory	･ Something abnormal in flush	･ Make a service call.
	fault	memory.
		･ Output current declined to the	･ Check to see if low-current detection
	low-current	low-current detection level during	level is set properly to the system or
(*1)		operation.	not ().
	operation
			･ If low-current detection level is
			properly set, make a service call.

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