[SM-P00049-A]
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28
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INSTALLATION
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2) Wiring of twist pair cable
When connecting a twist pair cable to this slave station unit, connect the DA (blue), DB
(white), and DG (yellow) wires in the cable to the DA, DB, and DG terminals respec-
tively, and connect the shield jacket to the SLD terminal. Ground the FG terminal
without fail (grounding resistance 100 ohms or less).
An example of cable connections is given below.
Twist pair cable with shield.
Note :
This slave station unit (OPP3-1G) does not use two-piece type terminal blocks. The data links, therefore, have
to be shut down when you replace the slave station unit.
If you wish to replace a slave station unit that constitutes the end station and a terminal resistor is connected
with it, you will have to connect the terminal resistor to the station positioned before the end station before you
disconnect the end station for replacement.
3) Wiring the source of power
The power circuit for the slave station unit (OPP3-1G) can be isolated from the power
circuit for the solenoid valve system. Moreover, two separate power sources can be used
to supply power independently to the slave station unit and the solenoid valve system.
The illustrations below are examples of power supply to two or more slave stations (re-
mote I/O units) from power source(s) at a single location. You may try other variations
as required.
NOTE : When designing the system to supply power to duplex number of slave stations and remote I/O stations, choose
and wire the source of power cord with a consideration of voltage drop. Secure ample voltage within rating by
providing dual wiring, if necessary, to keep as small voltage loss of single system as possible or installing source
of power near-by solenoid.
Fore station
DA
DB
DG
SLD
(FG)
D
A
D
B
F
G
D
G
S
L
D
SLD
DG
DB
DA
(FG)
Aft station
Slave station
0V 24V
Unit
power
0V
24V
Valve
power
①
Common connection of Unit
power and Valve power
0V 24V
Unit
power
0V
24V
Valve
power
②
Wiring to enable Valve power
to be turned On
･
Off.
0V
24V
Unit
power
0V
24V
Valve
power
③
Seperate connection Unit
power with Valve power
aft
station
Source of
Power DC
Unit
power
Valve power
Switch for Valve power
Source of
Power DC
aft
station
aft
station
