Wiring Examples For Connecting The Sdm-Sio1A; Rs-485/Rs-422 Full-Duplex, One-To-One Connection Example - Campbell SDM-SIO1A Instruction Manual

SDM-SIO1A Serial Input/Output Module
NOTE

6.2.1 Wiring Examples for Connecting the SDM-SIO1A

6.2.1.1 RS-485/RS-422 Full-Duplex, One-to-One Connection Example

10
The connection of the wires to the remote serial device will vary with type of
device and method of communication. It is necessary to work out the best
mode of operation of the serial device, taking into consideration issues such as
power consumption, cable lengths (RS-485 being better than RS-232 for long
cables), synchronization of data collection, etc.
If possible, use screened cable for connecting the SDM-SIO1A to
remote sensors or devices. Check the manual of the device for
details on where to connect the screen for maximum effectiveness.
RS-422 mode is functionally the same as RS-485 mode except the connection
is limited to a point-to-point system. Connections and programming for
RS-422 are otherwise identical to full-duplex RS-485.
When operating in RS-232 mode, the SDM-SIO1A also supports hardware
handshaking.
Section 6.2.1, Wiring Examples for Connecting the SDM-SIO1A
examples of different connection schemes for the serial devices. Further
discussion of different modes of operation is given in Section 7, Operation
The exact method of wiring the SDM-SIO1A varies with the type of device it
is going to exchange data with. The variables include the type of interface used
(RS-232, RS-485, or RS-422), whether handshaking is used, whether the
connection is full or half duplex, and whether termination resistors are used
(RS-485 and RS-422 only).
Typical wiring for the most common configurations are given as examples in
the following subsections.
, provides
(p. 10)
.
(p. 22)