2-26
2-2-4 Wiring for Noise Resistance
H
Wiring Method
Noise resistance will vary greatly depending on the wiring method used. Resistance to noise can be
increased by paying attention to the items described below.
RE
R
T
U
V
W
CN2
M
MCCB
3.5mm
2
Servomotor
R88M-
U
jjjjjj
Servo Driver
R88D-
U
jjjj
2 mm
2
min.
1
2
3
4
NF
E
X1
TB
TB
AC power supply
Surge
absorber
Noise filter Contactor
Metal duct
Fuse
Class-3 ground
(to 100
Ω
or less) Ground plate
Control board
ground
Controller power supply
Thick power line
(3.5 mm
2
)
Machine
ground
•
Ground the motor’s frame to the machine ground when the motor is on a movable shaft.
•
Use a grounding plate for the frame ground for each Unit, as shown in the illustration, and ground to a
single point.
•
Use ground lines with a minimum thickness of 3.5 mm
2
, and arrange the wiring so that the ground lines
are as short as possible.
•
If no-fuse breakers (MCCB) are installed at the top and the power supply line is wired from the lower
duct, use metal tubes for wiring and make sure that there is adequate distance between the input lines
and the internal wiring. If input and output lines are wired together, noise resistance will decrease.
•
No-fuse breakers (MCCB), surge absorbers, and noise filters (NF) should be positioned near the input
terminal block (ground plate), and I/O lines should be isolated and wired using the shortest means
possible.
•
Wire the noise filter as shown at the left in the following illustration. The noise filter should be installed
at the entrance to the control panel whenever possible.
1
2
3
4
NF
E
1
2
3
4
NF
E
Good:
Separate input and output
AC input
Ground
AC output
NO:
Noise not filtered effectively
AC input
Ground
AC output
System Design and Installation
Chapter 2
