1) noise filter, 2) correct grounding, Grounding the motor frame – Yaskawa Sigma-5 User Manual: Design and Maintenance - Linear Motors User Manual
Page 87: Noise on the i/o signal line

3.8 Noise Control and Measures for Harmonic Suppression
3-41
3
Wiring and Connection
(1) Noise Filter
The SERVOPACK has a built-in microprocessor (CPU), so protect it from external noise as much as possible
by installing a noise filter in the appropriate place.
The following is an example of wiring for noise control.
∗1. For ground wires connected to the ground plate, use a thick wire with a thickness
of at least 2.0 mm
2
(preferably, plain stitch cooper wire).
∗2.
should be twisted-pair wires.
∗3. When using a noise filter, follow the precautions in 3.8.2 Precautions on Con-
necting Noise Filter.
(2) Correct Grounding
Take the following grounding measures to prevent the malfunction due to noise.
Grounding the Motor Frame
Always connect linear servomotor frame terminal FG to the SERVOPACK ground terminal . Also be sure
to ground the ground terminal .
If the linear servomotor is grounded via the machine, a switching noise current will flow from the SERVO-
PACK main circuit through linear servomotor stray capacitance. The above grounding is required to prevent
the adverse effects of switching noise.
Noise on the I/O Signal Line
If the I/O signal lines are affected by noise, ground the 0 V (SG) terminal of I/O signal. If the main circuit wir-
ing for the motor is in a metal conduit, ground the conduit and its junction box. For all grounding, ground at
one point only.
U
W
V
L2
L1
L3
L2C
L1C
CN2
CN1
ENC
(FG)
M
SERVOPACK
Operation relay
sequence
Signal generation
circuit (not included)
Noise
Filter
DC
power
(Ground plate)
2.0 mm
min.
2
200 VAC
Noise filter *3
*1
*3
*2
2.0 mm
2
min .
Ground: Ground to an independent ground
2.0 mm min.
2
*1
Linear servomotor