OPERATION MANUAL CompoBus/S

CompoBus/S System Configuration Section 1-2
Flat Cable is used, the communications power supply can be supplied through
the cable. The system shown in the preceding diagram uses 4-conductor
VCTF or Special Flat Cable. When 2-conductor VCTF cable is used, power
must be supplied to the Slaves through a separate cable.
Connection Methods Two methods can be used to connect CompoBus/S Slaves: the T-branch
method and the multidrop method. With the T-branch method, the Slave is
connected to a branch line which branches off from the main line. With the
multidrop method, the Slave is connected directly to the main line.
These two connection methods can both be used in the same system,
although it is not possible to make a secondary branch from a branch line.
Use OMRON’s Branch Connector, a T-joint for a shielded connector, or a commercially
available terminal block to create a branch from the main line.
Terminator A terminator must be connected to the end of the main line opposite the Master
in order to stabilize communications. There are three kinds of terminating
resistors available, a connector for use with Special Flat Cable, a terminal
block, and a shielded connector.
System with No Distinction between Main and Branch Lines
The diagram below shows a CompoBus/S System in which it is not necessary
to distinguish between the main line and branch lines. This applies to the following
conditions.
The system operates in Long-distance Communications Mode with 4-conductor
VCTF cable.
The system operates in Long-distance Communications Mode with Special
Flat Cable.
(The maximum length of cable is 200 m regardless of the type of communications
cable.)
Slave
Slave
Communications
Power
Supply
Slave
Slave
Master
Slave
Slave
Communications cable
Power supply cable
T: T-branch connection
M: Multidrop connection
Terminator
Master The Master administers the CompoBus/S System and manages the external
I/O of the Slaves. There is only one Master in a CompoBus/S System and the
Master can be connected anywhere.
Slaves The external I/O connected to the Slaves is processed by communicating with
the Master through the CompoBus/S System.
Slave
Slave
Slave
Slave
Slave
Slave Slave Slave
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