Miller Electric D-74D manual Diagnostics

7-2.	Diagnostics
	1 LED3 On Right Side Motor
	Control Board PC1
	2 LED3 On Left Side Motor
	Control Board PC101
	3 LED3 On Dual Board PC70
	2
	3
	1
	803 063-A

		Display On	LED3 Sequence			Indicated Error
		Optional Meter
Left Side Motor Control		HELP 11	1 Blink			Communication Error
Board PC101		HELP 12	2 Blinks			Trigger Error
		HELP 13	3 Blinks			Tach Error
		HELP 14	*4 Blinks			Motor Error
Right Side Motor Control		HELP 21	1 Blink			Communication Error
Board PC1		HELP 22	2 Blinks			Trigger Error
		HELP 23	3 Blinks			Tach Error
		HELP 24	*4 Blinks			Motor Error
Dual Board PC70		HELP 31	*4 Blinks			Communication Error
	*Since blink On time and blink Off time are equal in a four-blink
	cycle, the four−blink sequence appears as constant blinking.
• Error Indications		a lower one (if a motor error and a communica-			ride is not enabled), or if the user holds the
Error conditions are indicated by LED3 on		tion error existed, the light would blink four			trigger past the postflow phase in a timed
		times for the motor error).			weld. This error also occurs if the trigger is
PC1, PC101, PC70 or on display if meter op-
					held when the feeder is powered up. The er-
tion is present. To view LED3, turn Off unit, re-		• The communication error occurs 2.5 sec-
					ror may be cleared by releasing the trigger.
move wrapper, and turn unit On. LED3 is most		onds after a loss of communication between
easily observed from the left side of the unit.		the motor and the optional meter board or		• The tach error occurs 2 seconds after the
The LED blinks in a 2.5 second cycle. The		Dual board. The user may continue to weld			loss of tachometer feedback. The user may
number of blinks in this period indicates the		with this error. The error may be cleared by			continue to weld with this error. The motor
type of error.		turning power Off, waiting a minimum of two			speed is regulated through the monitoring of
The priority of the errors is related to the num-		seconds, and turning power On.			voltage and current.
		• The trigger error occurs if the user has the		• The motor error indicates that the motor
ber of blinks indicating the error. The more
blinks, the more severe the error (motor error		trigger held for more than two minutes with-			has been drawing too much current for too
is top priority). A higher priority error overrides		out striking an arc (providing current over-			long.

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