5.7 Troubleshooting Based on the Operation and Conditions of the Servomotor
5-48
Absolute
Encoder
Position
Deviation
Error (The
position
that was
saved in the
host con-
troller when
the power
was turned
OFF is dif-
ferent from
the posi-
tion when
the power
was next
turned ON.)
The encoder was sub-
jected to excessive
vibration or shock.
Turn OFF the power supply
to the servo system.
Check to see if vibration
from the machine occurred.
Check the Servomotor
installation (mounting sur-
face precision, securing
state, and alignment).
Reduce machine vibra-
tion. Or, improve the
mounting conditions of the
Servomotor.
–
A failure occurred in the
encoder.
–
Turn OFF the power supply
to the servo system.
Replace the Servomotor.
–
A failure occurred in the
SERVOPACK.
–
Turn OFF the power supply
to the servo system.
Replace the SERVOPACK.
–
Host Controller Multi-
turn Data or Absolute
Encoder Position Data
Reading Error
Check the error detection
section of the host control-
ler.
Correct the error detection
section of the host control-
ler.
–
Check to see if the host
controller is executing data
parity checks.
Perform parity checks for
the multiturn data or abso-
lute encoder position data.
–
Check for noise interfer-
ence in the cable between
the SERVOPACK and the
host controller.
Implement countermea-
sures against noise and
then perform parity checks
again for the multiturn data
or absolute encoder posi-
tion data.
–
Overtravel
Occurred
The P-OT/N-OT (For-
ward Drive Prohibit or
Reverse Drive Prohibit)
signal was input.
Check the external power
supply (+24 V) voltage for
the input signals.
Correct the external power
supply (+24 V) voltage for
the input signals.
–
Check the operating condi-
tion of the overtravel limit
switches.
Make sure that the over-
travel limit switches oper-
ate correctly.
–
Check the wiring of the
overtravel limit switches.
Correct the wiring of the
overtravel limit switches.
*
Check the settings of the
overtravel input signal allo-
cations (Pn50A/Pn50B).
Set the parameters to cor-
rect values.
*
The P-OT/N-OT (For-
ward Drive Prohibit or
Reverse Drive Prohibit)
signal malfunctioned.
Check for fluctuation in the
external power supply (+24
V) voltage for the input sig-
nals.
Eliminate fluctuation from
the external power supply
(+24 V) voltage for the
input signals.
–
Check to see if the opera-
tion of the overtravel limit
switches is unstable.
Stabilize the operating
condition of the overtravel
limit switches.
–
Check the wiring of the
overtravel limit switches
(e.g., check for cable dam-
age and loose screws).
Correct the wiring of the
overtravel limit switches.
–
Continued on next page.
Continued from previous page.
Problem
Possible Cause
Confirmation
Correction
Reference