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
1750-4xx16.0 - 16.15--RO
2750-4xx17.0 - 17.15--RO
3750-4xx18.0 - 18.15--RO
4750-4xx19.0 - 19.15--RO
5750-4xx20.0 - 20.15--RO
6750-4xx21.0 - 21.15--RO
7750-5xx-4.0 - 4.15516.0 - 516.15RO
8750-5xx-5.0 - 5.15517.0 - 517.15RO
9750-5xx-6.0 - 6.15518.0 - 518.15RO
10750-5xx-7.0 - 7.15519.0 - 519.15RO
11750-5xx-8.0 - 8.7520.0 - 520.7RO
12750-455/000-0000 - 3--RO
13750-455/000-0004 - 7--RO
14750-455/000-0008 - 11--RO
15750-455/000-00012 - 15--RO
16750-555/000-000-0 - 3512 - 515RO

  Modbus Coils [bit addresses]
I/O Module Order Number input (RO) output (WO) output (RW) I/O access
1750-4xx0 - 15--RO
2750-4xx16 - 31--RO
3750-4xx32 - 47--RO
4750-4xx48 - 63--RO
5750-4xx64 - 79--RO
6750-4xx80 - 95--RO
7750-5xx-0 - 15512 - 527RO
8750-5xx-16 - 31528 - 543RO
9750-5xx-32 - 47544 - 559RO
10750-5xx-48 - 63560 - 575RO
11750-5xx-64 - 71576 - 583RO
12750-455/000-000----
13750-455/000-000----
14750-455/000-000----
15750-455/000-000----
16750-555/000-000----
 
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