User`s manual

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3 DESIGN
3.2.1 Power supply circuit design
This section describes the protective coordination and noise suppression techniques of
the power supply circuit.
(1) Separation and protective coordination (leakage current protection,
over current protection) of power supply lines
Separate the lines for Multiple CPU system power supplies from the lines for I/O
devices and servo amplifiers as shown below.
When there is much noise, connect an insulation transformer.
Multiple CPU
system
PLC power
supply
Main power
supply
I/O power
supply
Main circuit
power supply
I/O devices
Main circuit device
Insulation
transformer
100/200VAC
T1
NFB
CP
CP
CP
200VAC
NFB
Servo amplifier
Servo amplifier
power supply
(2) Grounding
The Motion system may malfunction as it is affected by various noises such as
electric path noises from the power supply systems, radiated and induced noises
from other equipment, servo amplifiers and their cables, and electromagnetic
noises from conductors. To avoid such troubles, connect the earthing ground of
each equipment and the shield grounds of the shielded cables to the earth.
For grounding, use the exclusive ground terminal wire of each equipment or a
single-point earth method to avoid grounding by common wiring, where possible,
since noises may sneak from other equipment due to common impedances.
Line noise filter
Multiple CPU system
100/200VAC
SSCNET
Servo amplifier
Servo-
motor
(Note): Be sure to ground the line noise filter, Multiple CPU system, servo amplifier and
servomotor. (Ground resistance : 100
or less
)