GW-7552-B / GW-7552-M PROFIBUS/MODBUS GATEWAY User Manual
(Version 1.60, May/2017)
PAGE: 12
slave in a local RS-485 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-485 network device the four jumpers provided by the module has to be
set according to
Table 6
. The jumpers set the pull high and pull down resistors
for the RS-485 port (
Figure 9
).
Figure 8 RS-485 connection
Table 6 Jumper position for the RS-485 port
Pull high/low resistor
Condition
Enabled
(default)
The GW-7552-B / GW-7552-M is
the master in RS-485 bus or
the number of devices connected
to the RS-485 bus is less than 10
Disabled
The GW-7552-B / GW-7552-M is
a slave in RS-485 bus or
the number of devices connected
to the RS-485 bus exceeds 10
GW-7552-B/GW-7552-M
RS-485 Port
RS-485