WR-90 Point to Multi-Point Wireless Instruction Manual
28
Modbus RTU
Each field unit is capable of transmitting Modbus
®
RTU serial communications. Enter the Modbus network
settings on the Modbus tab in order to communicate with the Modbus network. The Modbus address must
be unique in order to ensure field unit/base station connectivity.
Once you have modified the settings, click the
Save Configuration
button to save these settings to the
field unit.
Modbus Register Address vs Modbus Register Number
In order to address the wireless units’ Modbus registers, depending on the type of Modbus device, it may
be necessary to provide either the
register address
or the
register number
. WR Manager shows the
register address
of input and output devices in the section labeled
Modbus Access
, as shown below:
In this example, if the Modbus device requires a
register
address
, use the value 2112 to access the long int value.
If the Modbus device requires a
register number
, add 40,001
to the
register address
(in this case: 42,113) to access the
long int value. The table at right shows additional
register
address
to
register number
conversions
Register Address Register Number
0
40,001
256
40,257
2048
42,049
3328
43,329
