Mitsubishi Electronics MR-J2S- A instruction manual AL.8A, Computer Personal computer faulty

10. TROUBLESHOOTING

Display	Name	Definition			Cause	Action
AL.51	Overload 2	Machine collision or	1.	Machine struck something.		1. Review operation pattern.
		the like caused max.				2. Install limit switches.
		output current to	2.	Wrong connection of servo motor.		Connect correctly.
		flow successively for		Servo amplifier's output terminals
		several seconds.		U, V, W do not match servo
		Servo motor locked:		motor's input terminals U, V, W.
		1s or more	3.	Servo system is instable and		1. Repeat acceleration/deceleration to
				hunting.		execute auto tuning.
						2. Change auto tuning response setting.
						3. Set auto tuning to OFF and make gain
						adjustment manually.
			4.	Encoder faulty.		Change the servo motor.
					Checking method
				When the servo motor shaft is
				rotated slowly with the servo off,
				the cumulative feedback pulses
				should vary in proportion to the
				rotary angle. If the indication
				skips or returns midway, the
				encoder is faulty.
AL.52	Error excessive	Droop pulse value of	1.	Acceleration/deceleration time		Increase the acceleration/deceleration
		the deviation		constant is too small.		time constant.
		counter exceeded	2.	Torque limit value (parameter		Increase the torque limit value.
		80k pulses.		No.28) is too small.
			3.	Motor cannot be started due to		1. Review the power supply capacity.
				torque shortage caused by power		2. Use servo motor which provides larger
				supply voltage drop.		output.
			4.	Position control gain 1 (parameter		Increase set value and adjust to ensure
				No.6) value is small.		proper operation.
			5.	Servo motor shaft was rotated by		1. When torque is limited, increase the
				external force.		limit value.
						2. Reduce load.
						3. Use servo motor that provides larger
						output.
			6.	Machine struck something.		1. Review operation pattern.
						2. Install limit switches.
			7.	Encoder faulty		Change the servo motor.
			8.	Wrong connection of servo motor.		Connect correctly.
				Servo amplifier's output terminals
				U, V, W do not match servo
				motor's input terminals U, V, W.
AL.8A	Serial	RS-232C or RS-422	1.	Communication cable breakage.		Repair or change communication cable
	communication	communication	2.	Communication cycle longer than		Set correct value in parameter.
	time-out	stopped for longer		parameter No. 56 setting.
		than the time set in	3.	Wrong protocol.		Correct protocol.
		parameter No.56.
AL.8E	Serial	Serial	1.	Communication connector is		Connect correctly.
	communication	communication		disconnected.
	error	error occurred
			2.	Communication cable fault		Repair or change the cable.
		between servo
				(Open cable or short circuit)
		amplifier and
		communication
			3.	Communication device (e.g.		Change the communication device (e.g.
		device (e.g. personal
		computer).		personal computer) faulty		personal computer).

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