12.2 Troubleshooting
Alarm Code
(Alarm/warning History)
Status When Lit
Cause
Remedy
"DO"
O v e r f l o w i n g
No feedback pulse after mov-
reference input
Servomotor wiring incorrect.
Encoder wiring incorrect.
• Check and correct Servo-
motor wiring.
• Check to see if the Phase-A,
-B and -C pulses are correct
at 2CN, and repair (discon-
nection, short, no power
supply, defective circuit
board.) if necessary.
Control board
(1PWB)
defective.
Replace SERVOPACK.
Overflow during high-speed
running
Servomotor wiring incorrect.
Encoder wiring incorrect.
• Check and correct Servo-
motor wiring.
• Check to see if the Phase-A,
-B and -C pulses are correct
at 2CN, and repair (discon-
nection, short, no power
supply, defective circuit
board.) if necessary.
User constant setting incorrect.
Set the correct user constant.
Control board (IPWB) defective.
Replace SERVOPACK.
Normal running by overflow
with large move reference
input
SERVOPACK adjustment incorrect. Increase speed loop gain
(Cn-0004).
Load capacity too large.
Review the load. (overload or
load inertia)
Feed speed too large.
Decrease the feed speed.
"71"
Instantaneous overload
Lit during driving
Operation resumes after
turning power OFF and ON.
Load greatly exceeds the rated torque
from several seconds to tens second.
Review the load. (overload)
"72"
Continuous overload
Lit during operation
Operation resumes after
turning power OFF and ON.
Load greatly exceeds the rated torque
from ten seconds to hundreds
second.
Review the load. (overload)
"80"
Absolute encoder error
(only if an
absolute
encoder is used)
At control power supply ON
Faulty absolute encoder wiring (PA,
PB, PC).
Check absolute encoder
con-
nections.
Absolute encoder malfunction.
Send the SENS_OFF com-
mand and resend the
SENS_ON command.
Control board (1PWB) defective.
Replace SERVOPACK.
During Servomotor driving
Absolute encoder
error occurred.
Send the SENS_OFF com-
mand and resend the
SENS_ON command.
SERVOPACK miscounted pulses
(incorrect position) or malfunctioned
due to
noise.
Separate encoder wiring from
main circuits, transfer the
SENS_OFF command (servo
OFF if driving) and resend the
SENS_ON command.
Number of encoder pulses set incor-
rectly.
Reset the correct number of en-
coder pulses.
12 -7