06161H DCN7969
Teledyne API Model 465H O
3
Monitor User Manual
41
8.3.
RS-232 Configuration
The RS-232 configuration is usually used when making a one-to-one connection between
the instrument and a single computer or PLC. The communications protocol used for the
RS-232 configuration is MODBUS
®
RTU. For details on the MODBUS
®
RTU
specification, please see
http://www.modbus.org/
.
With the instrument configured for RS-232, connection can be made to the DB-9
connector, labeled “RS232/485”, or to the three “COM” pins on the “General I/O”
connector. Only one of these connections should be used, the other must be left un-
connected. Table 8-1 below details the pinouts of these two connectors:
Table 8-1: RS-232 Connector Details
Function
DB-9
Connector Pin
(SW2 – DTE)
DB-9
Connector Pin
(SW2 – DCE)
General I/O
Connector
Transmit (Tx)
3
2
‘T’
Receive (Rx)
2
3
‘R’
Ground
5
5
‘G’
The serial port setup for RS-232 configuration is shown in Table 8-2 below:
Table 8-2: RS-232 Port Setup
Property
Value
Baud Rate
57600
Data Bits
8
Parity
None
Stop Bits
1
Flow Control
None
NOTE
A DTE-DCE switch is provided so that the instrument can be
connected to another device using either a straight-through or
crossover (Null-Modem) cable. See Section 8.2 for details on
changing this configuration.
Summary of Contents for 465H
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