GW-7552-B / GW-7552-M PROFIBUS/MODBUS GATEWAY User Manual
(Version 1.60, May/2017)
PAGE: 10
2.3.2 RS-422 connection
The RS-422 wiring connection is shown in
figure 5
.
The GW-7552-B / GW-7552-M gateway can be a Modbus master or Modbus
slave in a local RS-422 network. Depending on whether the gateway acts as a
Modbus master or as a Modbus slave and on the number of devices connected to
the RS-422 network device the four jumpers provided by the module has to be
set according to
table 5
. The jumpers set the pull high and pull down resistors
for the RS-422 port (
Figure 6, Figure 7
).
Figure 5 RS-422 connection
Table 5 Jumper position for the RS-422 port
Pull high/low resistor
Condition
Enabled
(default)
The GW-7552-B / GW-7552-M is the
master in RS-422 bus or
the number of devices connected to
the RS-422 bus is less than 10
Disabled
The GW-7552-B / GW-7552-M is a
slave in RS-422 bus or
the number of devices connected to
the RS-422 bus exceeds 10
RS-422 port
GW-7552-B/GW-7552-M
RS-422 port
