Hitachi SJ700-2 Series service manual Cpu

Name	Description		Display on		Display on	Troubleshooting and corrective action
		digital operator		remote operator
	If the inverter input voltage drops, the					Check whether the power supply voltage has
	control circuit of the inverter cannot
	function normally. Therefore, the inverter					dropped.
	shuts off its output when the input					(Check the power supply.)
Undervoltage	voltage falls below a specified level.				Under.V	Check whether the power supply capacity is
	The inverter will trip if the DC voltage					sufficient.
	across the P and N terminals exceeds					(Check the power supply.)
	about 175 VDC (in case of the 200 V					Check whether the thyristor has been damaged.
	class models) or about 345 VDC (in case					(Check the thyristor.)
	of the 400 V class models).
	If an error occurs in the internal current
	detector (CT), the inverter will shut off its					Check whether the inverter has failed.
CT error	output and display the error code shown				CT
	on the right. The inverter will trip when					(Repair the inverter.)
	the CT outputs about 0.6 V or more at
	power-on.
	If the internal CPU malfunctions or an					Check for the noise sources located near the
	error occurs in it, the inverter will shut off
						inverter.
CPU error	its output and display the error code				CPU	(Remove noise sources.)
(*3)	shown on the right.
						Check whether the inverter has failed.
	Note: Reading an abnormal data from
						(Repair the inverter.)
	the EEPROM may result in a CPU error.
	If an error occurs in the external					Check whether an error has occurred in the
	equipment or device connected to the					external equipment (when the external trip
External trip	inverter, the inverter will fetch the error				EXTERNAL	function has been enabled).
	signal and shut off its output. (This					(Recover the external equipment from the error.)
	protective function is enabled when the
	external trip function is enabled.)
	A USP error is indicated when the					Check whether the inverter power has been
	inverter power is turned on with an input					turned on with an input operation signal remaining
USP error	operation signal remaining in the				USP	in the inverter (when the USP function has been
	inverter. (This protective function is					enabled).
	enabled when the USP function is					(Reset the operation command, and then turn on
	enabled.)					the inverter power.)
	When the inverter power is turned on,					Check for the ground fault.
	this protective function detects the					(Check the output cables and motor.)
Ground-fault	ground fault between the inverter output					Check the inverter itself for abnormality.
protection	circuit and the motor to protect the				GND.Flt	(Remove the output cables from the inverter, and
	inverter. (This function does not operate					then check the inverter.)
(*3)
	when a residual voltage remains in the					Check the main circuit for abnormality.
	motor.)					(Check the main circuit with reference to
						Chapter 6.) (Repair the inverter.)
	This protective function determines an					Check whether the input voltage is high while the
	error if the input voltage is kept above					inverter is stopped.
Input	the specification level for 100 seconds					(Lower the input voltage, suppress the power
	while the inverter is stopped.					voltage fluctuation, or connect an AC reactor
					OV.SRC
overvoltage	The inverter will trip if the DC voltage of					between the power supply and the inverter input.)
protection	the main circuit is kept above about 390
	VDC (in case of the 200 V class models)
	or about 780 VDC (in case of the 400 V
	class models).
	If an instantaneous power failure lasts 15					Check whether the power supply voltage has
	ms or more, the inverter will shut off its					dropped.
Instanta-	output.					(Recover the power supply.)
	When the power failure duration is long,					Check the MCB and magnetic contactors for poor
neous power	the inverter assumes a normal power-off.				Inst.P-F	contacts.
failure	If a restart mode has been selected and					(Replace the MCB and the magnetic contactor.)
protection
	an operation command remains in the
	inverter, the inverter will restart after the
	power is recovered.
Temperature	The inverter will display the error code					Check whether the cooling efficiency has been
error due to	shown on the right if the lowering of					lowered.
low	cooling-fan speed is detected at the				OH.stFAN	(Replace the cooling fan.)
cooling-fan	occurrence of the temperature error					Check the heat sink for clogging.
speed	described below.					(Clean the heat sink.)
Temperature	If the main circuit temperature rises					Check whether the inverter is installed vertically.
	because of a high ambient temperature				OH.fin	(Check the installation.)
error	or for other reasons, the inverter will shut					Check whether the ambient temperature is high.
	off its output.					(Lower the ambient temperature.)

*3 The inverter will not accept reset commands input via the RS terminal or entered by the STOP/RESET key. Therefore, turn off the inverter power.

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