Wiring Rs-485 Interface; Figure 3.1 Db9 And Rs-232 Wiring; Figure 3.2 Db25 And Rs-232 Wiring; Table 3.2 Wiring Rs-232 Interface - Omega i-SERIES User Manual

Figures 3.1 and 3.2 show the three-wire RS-232 connections between the host computer
using a 9-pin or 25-pin "D" connector and the i–Series device.
DB-9 CONNECTOR
6
1 2
Figure 3.1 Wiring between DB9 computer connector and RS-232 controller interface
14 15 16 17 18 17 20 21 21 23 24 25
1 2 3 4 5
Figure 3.2 Wiring between DB25 computer connector
Table 3.2 shows the pin connection assignments between the RS-232 connector on the
meter and the 9-pin or 25-pin "D" connectors of your computer.

Table 3.2 Wiring RS-232 Interface

PIN FUNCTION
Receive (Rx)
Transmit (Tx)
Common ground

3.3 Wiring RS-485 Interface

RS-485 interface uses a two wire communication system (one for transmitting and one
for receiving) plus a common wire to connect to the shield of a cable. It is recommended
to use a shielded cable with one twisted pair.
Use of twisted pair and shield will significantly improve noise immunity.
7 8 9
3 4 5
DB-25 CONNECTOR
6 7 8 9 10 11 12 13
and RS-232 controller interface
COMPUTER
DB9 DB25
2
3
5
6
i-SERIES
i-SERIES
i-SERIES
FUNCTION/
3 Transmit (Tx)
2 Receive (Rx)
7
LABEL
RTN