Yaskawa Sigma-5 User Manual: Design and Maintenance - Linear Motors - Manual (Page 285)

8 Troubleshooting
8-34
Position Error
(without alarm)
Noise interference due to improper
specifications of the cable for con-
necting serial converter unit.
The specifications of the cable for
connecting serial converter unit
must be:
Twisted-pair or twisted-pair
shielded wire with core
0.12 mm
2 min. and tinned annealed
copper twisted wire.
Use the cable for connecting serial
converter unit with the specified
specifications.
Noise interference because the
length of the cable for connecting
serial converter unit is too long.
Check the length of the cable for
connecting serial converter unit.
The length of the cable for connect-
ing serial converter unit must be 20
m max.
Noise influence due to damaged
cable for connecting serial con-
verter unit
Check the cable for connecting
serial converter unit to see if it is
bent or its sheath is damaged.
If the cable is damaged, replace the
cable for connecting serial con-
verter unit, and correct the cable
layout.
Excessive noise interference to the
cable for connecting serial con-
verter unit
Check if the cable for connecting
serial converter unit is bundled with
a high-current line or near high-cur-
rent line.
Change the layout of the cable for
connecting serial converter unit so
that no surge voltage is applied.
FG electrical potential varies by
influence of such machines on the
linear servomotor side as welders.
Check if the machine is correctly
grounded.
Ground the machine separately
from encoder side FG.
SERVOPACK pulse count error due
to noise
Check if the I/O signal cable from
the serial converter unit is influ-
enced by noise.
Take a measure against noise for the
serial converter unit wiring.
Excessive vibration and shock to
the serial converter unit
Check if machine vibration
occurred or serial converter unit
mounting such as mounting surface
precision, fixing is incorrect.
Reduce the machine vibration or
mount the serial converter unit
securely.
Noise interference due to improper
I/O signal cable specifications
The specifications of the I/O signal
cable must be:
Twisted-pair or twisted-pair
shielded wire with core
0.12 mm
2
min. and tinned annealed
copper twisted wire.
Use I/O signal cable with the speci-
fied 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
less than 3 m.
A linear scale fault occurred.
(The pulse count does not change.)
− Replace the linear servomotor.
A SERVOPACK fault occurred. − Replace the SERVOPACK.
Servomotor
Overheated
Ambient operating temperature is
too high. Measure the linear servomotor
ambient operating temperature. Reduce the ambient operating tem-
perature to 40
°C max.
Linear servomotor surface is dirty. Check visually.
Clean dust and oil from linear ser-
vomotor surface.
Linear servomotor overloaded Check the load status with monitor.
If overloaded, reduce load or
replace with larger capacity SER-
VOPACK and linear servomotor.
Polarity detection is not performed
correctly.
Check if the value of Un004 (Elec-
tric Angle 2) at an arbitrary position
is between
±10 degrees.
Correct the settings for the polarity
detection related parameter.
Problem Probable Cause Investigative Actions Corrective Actions