OPERATION MANUAL CompoBus/S

Supplying Power to the Slaves Section 2-3
2. If multiple CompoBus/S Systems are used, provide a separate communications
power supply for each CompoBus/S System to prevent unstable
operation due to unwanted noise paths in the power supplies of the CompoBus/S
Systems.
CompoBus/S
System 1
CompoBus/S
System 2
Master
Master
Communications
power supply (See note.)
Main line
Main line
3. When using CJ-series Master Units, use 6-pin communications connectors
that allow simultaneous connection of communications and power
supply cables. Power can be supplied to the Slaves easily by connecting
the communications power supply to the Master Unit without preparing the
communications cables, as shown in the following diagram.
The BS+ and BS– terminals of the CJ-series Master Unit’s communications
connector are connected internally. (The Master Unit does not use
the BS+ or BS– terminals.)
2-3-3 Limitations of Communications Cable Power Supply
Slave
Check the following points when using 4-conductor VCTF or Special Flat
Cable to supply power to Slaves.
The 4-conductor VCTF or Special Flat Cable’s allowable current
The Extension Connector’s allowable current
(when using an Extension Connector)
The allowable current of the CJ-series Master Unit’s communications connector
(when using CJ-series Master Units)
Cable length limit due to voltage drop
1. 4-conductor VCTF or Special Flat Cable’s Allowable Current
The allowable current through the 4-conductor VCTF or Special Flat Cable
depends on the ambient temperature, as shown in the following tables.
Slave
Slave Slave
Note: Use a separate communications power supply for each line.
Communications
Power
supply
Communications
power supply (See note.)
CJ-series
Master Unit
BS+
BDH
BDL
BS−
BS+
BS−
Power
supply
+
H
L
−
+
−
+
−
Special Flat Cable or
4-conductor VCTF
cable (Wiring Special
Flat Cable is easy as
it is connected to the
communications
connector in the
same order.)
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