Power Supply Circuit Design - Mitsubishi Q172CPU User Manual

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 systems
When wiring, separate the lines of Multiple CPU system power supplies from
those of the I/O equipment and servo amplifier as shown below.
When there is much noise, connect an insulation transformer.
Main power
supply
100/200VAC
NFB
200VAC
(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.
Also use ferrite cores (ex., ZCAT3035-1330(TDK make)) to prevent the sneak
noises from the SSCNET.
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.
100/200VAC
Line noise filter
(Note): Be sure to ground the line noise filter, Multiple CPU system, servo
amplifier and servomotor. (Ground resistance : 100
Insulation
PLC power
transformer
supply
CP
I/O power
T1
supply
CP
Main circuit
power supply
CP
Servo amplifier
power supply
NFB
Multiple CPU
system
Ferrite cores
SSCNET
Servo amplifier
3 - 12
Multiple CPU
system
I/O devices
Main circuit device
Servo amplifier
Panel personal
computer
Servo-
motor
or less )