Emerson ControlWave Instruction Manual page 44

ControlWave Instruction Manual (CI-ControlWave)
2-28
Pin
3
4
5
6
7
8
Table 2-11. RS-485 COM4 Port (Male DB9) Connector Pin Assignment
RS-485
Pin Signal
1
2 RXD-
3 TXD-
4 TXD+
5 ISOGND
6 RXD+
7
8
9
Since the RS-485 port is intended for network communications, refer to
Table 2-12 for the appropriate connections for wiring the master, first
slave, and nth slave.
Essentially, the master and the first slave transmit and receive data on
opposite lines; all slaves (from the first to the nth) are paralleled (daisy-
chained) across the same lines. Wire the master node to one end of the
RS-485 cable run using a 24-gauge paired conductor cable (such as a
Belden 9843).
: ControlWave only supports half-duplex RS-485 networks.
Note
Table 2-12. RS-485 Network Connections
From Master
TXD+
TXD–
RXD+
RXD–
ISOGND
Installation
RS-485
Signal RS-485 Description
RXD- Receive Data – Input
TXD- Transmit Data – Output
TXD+ Transmit Data + Output
ISOGND Isolated Ground
RS-485 Description
Receive Data - Input
Transmit Data - Output
Transmit Data + Output
Isolated Ground
Receive Data + Input
To First Slave
RXD+
RXD–
TXD+
TXD–
ISOGND
To nth Slave
RXD+
RXD–
TXD+
TXD–
ISOGND
Revised Nov-2010