Yaskawa Sigma-5 User Manual: Design and Maintenance - Linear Motors MECHATROLINK-III Communications Reference - Manual (Page 298)

8.4 Troubleshooting Malfunction Based on Operation and Conditions of the Servomotor
8-37
8
Trou
blesh
ooting
Position Error
(Without Alarm)
Noise interference due to incorrect
linear scale connection cable speci-
fications
The linear scale connection cable
must be tinned annealed copper
shielded twisted-pair or screened
unshielded twisted-pair cable with a
core of 0.12 mm
2
min.
Use the specified linear scale con-
nection cable.
Noise interference due to length of
linear scale connection cables. Check the length of the linear scale
connection cables.
The length of each cable must be
equal to or shorter than the maxi-
mum wiring length listed here.
• Connection cables for serial con-
verter unit: 20 m
• Connection cables for linear
scale: 15 m
• Connection cables for hall sensor:
15 m
Noise influence due to damaged lin-
ear scale connection cables.
Check if the linear scale connection
cables are bent and the sheaths are
damaged.
Replace the linear scale connection
cables and modify the cable layout.
Excessive noise to linear scale con-
nection cables.
Check if the linear scale connection
cables are bundled with a high-cur-
rent line or near a high-current line.
Change the cable layout so that no
surge is applied.
The FG potential varies because of
influence from machines on the ser-
vomotor side such as the welder.
Check if the machines are correctly
grounded. Properly ground the machines linear
scale FG.
SERVOPACK pulse count error due
to noise
Check if the I/O signal line from the
serial converter unit is influenced
by noise.
Take measures against noise in the
serial converter unit wiring.
Excessive vibration and shock to
the linear scale
Check if vibration from the machine
occurred or linear scale installation
is incorrect (mounting surface accu-
racy and fixing method).
Reduce the machine vibration or
mount the linear scale securely.
Noise interference due to improper
I/O signal cable specifications
The I/O signal cable must be tinned
annealed copper shielded twisted-
pair or screened unshielded twisted-
pair cable with a core of 0.12 mm
2
min.
Use input signal cable with the
specified specifications.
Noise interference due to length of
I/O signal cable
Check the I/O signal cable length.
The I/O signal cable length must be
no more than 3 m.
A linear scale fault occurred. (The
pulse count does not change.)
− Replace the linear scale.
A SERVOPACK fault occurred. − Replace the SERVOPACK.
Servomotor
Overheated
Ambient operating temperature too
high Measure the servomotor ambient
operating temperature. Reduce the ambient operating tem-
perature 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.
Polarity detection is not performed
correctly.
Check if the value of Un004 (elec-
trical angle 2 from polarity origin)
at an arbitrary position is between
±10 degrees.
Correct the settings for the polarity
detection related parameter.
(cont’d)
Problem Probable Cause Investigative Actions Corrective Actions