Configuration Units; Maximum Number Of Units; Models Of Configuration Units - Omron CJ2 CPU UNIT User Manual

2 Basic System Configuration and Devices
2-1-4

Configuration Units

Maximum Number of Units

A maximum of 10 Units can be connected to the CPU Rack for a CJ2 CPU Unit or to an Expansion
Rack. There are no restrictions in the number of each model of Unit based on location.
Note A fatal error will occur and the CPU Unit will not operate if more than the allowable number of Units is con-
nected to a CJ2 CPU Rack or to an Expansion Rack.

Models of Configuration Units

The Configuration Units with which the CJ2 CPU Unit can exchange data are classified into three
groups. The number of Units that can be mounted depends on the type of Unit.
Units
Basic I/O Units
Special I/O Units
CPU Bus Unit
2-14
Description
Basic I/O Units are used for discrete inputs and
outputs.
Special I/O Units are more advanced than Basic
I/O Units. They support functions other than dis-
crete inputs and outputs.
Examples:
Analog I/O Units and High-speed Counter Units
Special I/O Units have a smaller area for
exchanging data with the CPU Unit than CPU
Bus Units (including Network Communications
Units).
CPU Units are advanced units that exchange
data with the CPU Unit via the CPU bus.
Examples:
Network Communications Units and Serial Com-
munications Units
CPU Bus Units have a larger area for exchang-
ing data with the CPU Unit than Special I/O
Units.
Unit identifica- Number of
tion method mountable Units
Identified by the Up to 40 Basic I/O
CPU Unit accord- Units can be
ing to mounting mounted.
position.
Identified by the Up to 40 Special
CPU Unit using I/O Units can be
unit numbers 0 to mounted.
95 set with the (Depending on the
rotary switches on model, more than
the front panel of one unit number is
the Unit. used for one Unit.)
Identified by the Up to 16 CPU Bus
CPU Unit using Units can be
unit number 0 to F mounted.
set with the rotary
switch on the front
panel of the Unit.
CJ2 CPU Unit Hardware User's Manual