Hardware reference guide

CPU Modules
35013379 11/2011 139
Rear Panel Switches
Two rotary switches (refer to the illustration and table below) are located on the rear
panel of the CPU. They are used for setting Modbus Plus node and Modbus port
addresses.
NOTE: The highest address that may be set with these switches is 64.
SW1 (the top switch) sets the upper digit (tens) of the address; SW2 (the bottom
switch) sets the lower digit (ones) of the address. The illustration below shows the
correct setting for an example address of 11.
The following figure shows SW1 and SW2.
The following table shows the SW1 and SW2 address settings.
Valid Communication Port Parameters
Baud 19,200 1,200
9,600 600
7,200 300
4,800 150
3,600 134.5
2,400 110
2,000 75
1,800 50
Parity Enable/Disable Odd/Even
Data Bits 7 / 8
Stop Bits 1 / 2
Device Address 1 ... 247
SW1 and SW2 Adress Settings
Node Address SW1 SW2
1 ... 9 0 1 ... 9
10 ... 19 1 0 ... 9
20 ... 29 2 0 ... 9