Modbus Configuration
This page contains information on how the I/O modules are currently mapped in the Modbus process image and how the general Modbus register assignment is structured.
 
I/O Mapping
  Modbus Register [word addresses]
I/O Module Order Number input (RO) output (WO) output (RW) I/O access
1750-4xx20.0 - 20.7--RO
2750-4xx20.8 - 20.15--RO
3750-4xx21.0 - 21.7--RO
4750-4xx21.8 - 21.15--RO
5750-4xx22.0 - 22.7--RO
6750-559/000-000-0 - 3512 - 515RO
7750-559/000-000-4 - 7516 - 519RO
8750-559/000-000-8 - 11520 - 523RO
9750-497/000-0000 - 7--RO
10750-497/000-0008 - 15--RO
11750-5xx-12.0 - 12.7524.0 - 524.7RO
12750-5xx-12.8 - 12.15524.8 - 524.15RO
13750-5xx-13.0 - 13.7525.0 - 525.7RO
14750-5xx-13.8 - 13.15525.8 - 525.15RO
15750-460/000-00316 - 19--RO

  Modbus Coils [bit addresses]
I/O Module Order Number input (RO) output (WO) output (RW) I/O access
1750-4xx0 - 7--RO
2750-4xx8 - 15--RO
3750-4xx16 - 23--RO
4750-4xx24 - 31--RO
5750-4xx32 - 39--RO
6750-559/000-000----
7750-559/000-000----
8750-559/000-000----
9750-497/000-000----
10750-497/000-000----
11750-5xx-0 - 7512 - 519RO
12750-5xx-8 - 15520 - 527RO
13750-5xx-16 - 23528 - 535RO
14750-5xx-24 - 31536 - 543RO
15750-460/000-003----
 
General Modbus Mapping
  Input Register (FC3, FC4, FC23)
Modbus address Description
0x0000 - 0x00FFphysical input data
0x0100 - 0x01FFplc output variables data
0x0200 - 0x02FFphysical output data
0x0300 - 0x03FFplc input variables data
0x1000 - 0x2FFFspecial register data
0x3000 - 0x5FFFretain data
0x6000 - 0x62FBphysical input data
0x7000 - 0x72FBphysical output data
0x8000 - 0x8FFFretain data

  Output Register (FC6, FC16, FC22, FC23)
Modbus address Description
0x0000 - 0x00FFphysical output data
0x0100 - 0x01FFplc input variables data
0x0200 - 0x02FFphysical output data
0x0300 - 0x03FFplc input variables data
0x1000 - 0x2FFFspecial register data
0x3000 - 0x5FFFretain data
0x6000 - 0x62FBphysical output data
0x7000 - 0x72FBphysical output data
0x8000 - 0x8FFFretain data

  Digital Input (FC1, FC2)
Modbus address Description
0x0000 - 0x01FFphysical input data
0x0200 - 0x03FFphysical output data
0x1000 - 0x1FFFplc output variables data
0x2000 - 0x2FFFplc input variables data
0x3000 - 0x7FFFretain data
0x8000 - 0x85F7physical input data
0x9000 - 0x95F7physical output data

  Digital Output (FC5, FC15)
Modbus address Description
0x0000 - 0x01FFphysical output data
0x0200 - 0x03FFphysical output data
0x1000 - 0x1FFFplc input variables data
0x2000 - 0x2FFFplc input variables data
0x3000 - 0x7FFFretain data
0x8000 - 0x85F7physical output data
0x9000 - 0x95F7physical output data