Yaskawa Sigma-5 User Manual: Design and Maintenance - Linear Motors - Manual (Page 283)

8 Troubleshooting
8-32
Abnormal Noise
from Linear
Servomotor
(cont’d)
Noise interference due to incorrect
specifications of cable for connect-
ing serial converter unit.
The specifications of cable for con-
necting 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 specified cable for connect-
ing serial converter unit.
Noise interference because the
cable for connecting serial con-
verter unit is too long
Check the length of the cable for
connecting serial converter unit.
The length of cable for connecting
serial converter unit must be 20 m
max.
Noise interference because the
cable for connecting serial con-
verter unit is damaged
Check the cable for connecting
serial converter unit to see if it is not
damaged or bent.
Replace the cable for connecting
serial converter unit, and recon-
sider the layout of the cable for con-
necting serial converter unit.
Excessive noise to the cable for
connecting serial converter unit
Check if the cable for connecting
serial converter unit is not bundled
with high-current line or not near
the high-current line.
Modify the cable layout so that no
surge from high-current line is
applied to the cable for connecting
serial converter unit.
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 linear scale side FG.
SERVOPACK pulse counting error
due to noise
Check if there is noise interference
on the I/O signal cable from the
serial converter unit.
Take measure against noise for the
serial converter unit wiring.
Excessive vibration and shock to
the serial converter unit
Check if vibration from the machine
occurred or serial converter unit
installation is incorrect.
(Mounting surface accuracy, or fix-
ing.)
Reduce vibration from the machine,
or correct the serial converter unit
installation.
A serial converter unit fault
occurred.
− Replace the serial converter unit.
A linear scale fault occurred. − Replace the linear scale.
Linear
Servomotor
Vibrates at about
200 to 400 Hz
Unbalanced servo gains
Check to see if the servo gains have
been correctly adjusted.
Execute the advanced autotuning.
Speed loop gain value (Pn100) is
too high.
Check the speed loop gain value
(Pn100).
Factory setting: Kv = 40.0 Hz
Reduce the speed loop gain
(Pn100).
Position loop gain value (Pn102) is
too high.
Check the position loop gain value
(Pn102).
Factory setting: Kp = 40.0/s
Reduce the position loop gain
(Pn102).
Incorrect speed loop integral time
constant (Pn101) setting
Check the speed loop integral time
constant (Pn101) setting.
Factory setting: Ti = 20.0 ms
Correct the speed loop integral time
constant (Pn101) setting.
Incorrect mass ratio (Pn103) setting Check the mass ratio (Pn103) set-
ting.
Correct the mass ratio (Pn103) set-
ting.
Problem Probable Cause Investigative Actions Corrective Actions