Mitsubishi A1SD75M3

14 - 37
MELSEC-A
14 TROUBLESHOOTING
Relevant buffer memory
address
Axis 1 Axis 2 Axis 3
Checking method Remedy
1. Check the speed command (pulse train
frequency).
2. Check if the motor speed determined by the
set speed of the AD75 has exceeded the
rated speed of the servomotor.
Set the speed correctly. (600kpps or less)
1. Increase acceleration/deceleration time
constant.
2. Reduce the speed.
Reconsider the acceleration/deceleration time constant.
112 262 412
1. Adjust the servo gain.
2. Check " Pr.112 Load inertia ratio" (load
inertia moment ratio).
3. Increase the acceleration/deceleration time
constant.
4. Reduce the speed.
1. Re-set servo gain to proper value.
2. If setting cannot be made by the servo gain:
1) Reduce " Pr.112 Load inertia ratio" (load inertia
moment ratio); or
2) Reexamine the acceleration/deceleration time
constant.
Motor type
103 253 403
Motor speed
105 255 405
Check the servo parameters " Pr.103 Motor
type" and " Pr.105 Motor speed".
Set correctly.
1. Change the cable.
2. Change the servomotor.
Change the cable.
Change the servomotor.
Check if the U, V, W cables have been
connected using a tester.
Correct the wiring.
Measure the resistance across transistor
module terminals using a tester.
Change the transistor module or unit.
1. Check across terminal block U, V, W
phases and case using a tester.
2. Check across servomotor U, V, W phases
and core using a tester and megger.
Correct the ground fault.
Change the unit or servomotor.
Check if the relay or valve has operated in the
periphery.
Take noise suppression measures.
Check the connection across terminal block C-
P.
Connect correctly.
Check the resistance of the regenerative
power transistor using a tester.
Change the unit.
Measure across terminal block C-P using a
tester (measure about 3 minutes after the
charge lamp goes OFF).
Change the unit.
Measure the input voltage (R, S, T) with a
voltmeter.
Reconsider the power supply capacity.
Check for disconnection of the cable
connector.
Connect correctly.
Check for an open cable, etc. Change the cable.
The relay or valve has operated in the
periphery.
Take noise suppression measures.
Check for disconnection of the terminal
connector.
Connect correctly.
Check if the input pulse is faulty. Change the AD75.
Check if the relay or valve has operated in the
periphery.
Take noise suppression measures.