Host Types And Settings - Omron NT31 Operation Manuals

Connecting to the Host's RS-422A/485 Port
Reference: CS1 series CPUs cannot be connected with the 1:1 connection NT link method.
5-2-1

Host Types and Settings

When Using the Host Link Method
114
Note One end of the wire must always be connected to the host (PC), and there must be
no branching. Branching will cause problems such as transmission delays and
communication failures.
PC (At termination)
NT31C NT31
(Not at
(Not at
termination) (Not at
termination)
Example of Good Connection
Use the 1:N connection NT link method instead to make the 1:1 connection. For
details, refer to "Using the NT link (1:N) Method" (page 127)
The types of host that have an RS-422A port and can be connected to the
RS-422A/485 port of the NT31/NT31C, and the settings to be made at the host,
are described here.
S Compatible host units
Some models and series of OMRON PCs have the RS-422A/485 type host link
function built in. In a CS1 series, the host link method can be used by installing a
serial communication board. In addition, some C200HX/HG/HE (–Z) devices
have an integral CPU that can be connected in the host link method by installing
a communication board.
Check the model and series of the PC, the type of the installed serial commu-
nication board, the serial communication unit, and host link unit at the connection
end before making a connection.
The host units featuring the RS-422A/485 type host link function and can be con-
nected to the RS-422A/485 port of the NT31/NT31C are indicated in the table
below.
Relay terminal block
Max. 2 m
NT31 NT31
NT31
(At
termination)
termination)
PC
NT31C NT31 NT31
Examples of Bad Connections
Section 5-2
PC
Relay terminal block
NT31C NT31