65-2660XL-XX-04 M2A-XL Transmitter
Chapter 8: RS-485 Modbus Output
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47
Termination Jumper
The M2A-XL includes a 2-pin termination header (see Figure 3 on page 11) that is used when the
M2A-XL is used in a Modbus system. Every M2A-XL is supplied with a termination jumper (a
jumper block) installed onto this header. If the M2A-XL is not used in a Modbus system, this
jumper has no function. When the M2A-XL is installed in a Modbus system, this jumper must be
installed in an M2A-XL that is at the end of a Modbus line. Any M2A-XL in a Modbus system
that is not at the end of a line must have the termination jumper removed (see Figure 11 & Figure
12 below).
Figure 11: Multiple M2A-XLs in a Daisy Chain Configuration
Figure 12: Multiple M2A-XLs in a Two Branch Configuration
Modbus
Master
Up to 128 M2As can be connected without a repeater
RS-485
RS-485
ID = 126
ID = 127
M2A
Termination
Jumper
Not Installed
M2A
Termination
Jumper
Not Installed
ID = 128
M2A
Termination
Jumper
Installed
ID = 125
ID = 1
M2A
Termination
Jumper
Not Installed
M2A
Termination
Jumper
Not Installed
ID = 128
RS-485
M2A
Termination
Jumper
Installed
Modbus
Master
Up to 128 M2As can be connected without a repeater
M2A
Termination
Jumper
Not Installed
M2A
Termination
Jumper
Not Installed
M2A
Termination
Jumper
Not Installed
M2A
Termination
Jumper
Not Installed
ID = 2
ID = 3
RS-485
ID = 1
M2A
Termination
Jumper
Installed
ID = 127
ID = 4