User`s manual

9.3 Troubleshooting Malfunction Based on Operation and Conditions
9-23
9
Troubleshooting
Position Error
(Without Alarm)
Noise interference due to improper
encoder cable specifications
The encoder cable must be tinned
annealed copper shielded twisted-
pair or shielded multi-core twisted-
pair cable with a core of 0.12 mm
2
min.
Use the specified encoder cable.
Noise interference due to length of
encoder cable
Check the encoder cable length.
The encoder cable must be no
longer than 20 m.
Noise influence due to damaged
encoder cable
Check if the encoder cable is bent or
if its sheath is damaged.
Replace the encoder cable and cor-
rect the encoder cable layout.
Excessive noise interference to
encoder cable
Check if the encoder cable is bun-
dled with a high-current line or near
a high-current line.
Correct the encoder cable layout so
that no surge from high-current
lines is applied.
FG potential varies because of
influence of machines such as weld-
ers at the servomotor.
Check if the machines are correctly
grounded.
Ground machines correctly, and
prevent diversion to the FG at the
PG side.
SERVOPACK pulse counting error
due to noise interference
Check if there is noise interference
on the I/O signal line from the
encoder.
Take measures against noise in the
encoder wiring.
Excessive vibration and shock to
the encoder
Check if vibration from the machine
occurred or servomotor installation
is incorrect (mounting surface accu-
racy, fixing, alignment, etc.).
Reduce vibration from the machine,
or secure the servomotor installa-
tion.
Unsecured coupling between
machine and servomotor
Check if a position error occurs at
the coupling between machine and
servomotor.
Secure the coupling between the
machine and servomotor.
Noise interference due to improper
I/O signal cable specifications
The I/O signal cable must be tinned
annealed copper shielded twisted-
pair or shielded multi-core twisted-
pair cables with a core of 0.12 mm
2
min.
Use the specified I/O signal cable.
Noise interference due to length of
I/O signal cable
Check the I/O signal cable length.
The I/O signal cable must be no
longer than 3 m.
An encoder fault occurred. (The
pulse count does not change.)
– Replace the servomotor.
A SERVOPACK fault occurred. – Replace the SERVOPACK.
Servomotor
Overheated
Ambient temperature too high
Measure the servomotor ambient
temperature.
Lower the ambient temperature to
40°C or less.
Servomotor surface dirty Visually check the surface. Clean dust and oil from the surface.
Servomotor overloaded Check the load status with monitor.
If overloaded, reduce load or
replace with larger capacity SER-
VOPACK and servomotor.
(cont’d)
Problem Probable Cause Investigative Actions Corrective Actions