Readout Examples
Readout Example of a Modbus Register
The table below shows how to read the rms current on phase 1 (I1) in register 12016.
-
The address of register 12016 equals 12016 - 1 = 12015 = 0x2EEF.
-
The Modbus address of the Modbus slave is 47 = 0x2F.
|
Request from the Master |
Response from the Slave |
||
|---|---|---|---|
|
Field Name |
Example |
Field Name |
Example |
|
Modbus slave address |
0x2F |
Modbus slave address |
0x2F |
|
Function code |
0x03 |
Function code |
0x03 |
|
Address of register to be read (MSB) |
0x2E |
Data length in bytes |
0x02 |
|
Address of register to be read (LSB) |
0xEF |
Register value (MSB) |
0x02 |
|
Number of registers (MSB) |
0x00 |
Register value (LSB) |
0x2B |
|
Number of registers (LSB) |
0x01 |
CRC (MSB) |
0xXX |
|
CRC (MSB) |
0xXX |
CRC (LSB) |
0xXX |
|
CRC (LSB) |
0xXX |
– |
– |
The content of register 12016 (address 0x2EEF) is 0x022B = 555.
The rms current on phase 1 (I1) is thus 555 A.
Readout Example of the Table of Legacy Dataset Common Registers
The table below shows how to read the table of legacy dataset common registers. This table starts at register 12000 and consists of 113 registers.
-
The address of register 12000 = 0x2EDF.
-
The table length is 113 registers = 0x71.
-
The number of bytes is 113x2 = 226 bytes = 0xE2.
-
The Modbus address of the slave is 47 = 0x2F.
|
Request from the Master |
Response from the Slave |
||
|---|---|---|---|
|
Field Name |
Example |
Field Name |
Example |
|
Modbus slave address |
0x2F |
Modbus slave address |
0x2F |
|
Function code |
0x03 |
Function code |
0x03 |
|
Address of the first register to be read (MSB) |
0x2E |
Data length in bytes |
0xE2 |
|
Address of the first register to be read (LSB) |
0xDF |
Value of register 12000 (MSB) |
0xXX |
|
Number of registers (MSB) |
0x00 |
Value of register 12000 (LSB) |
0xXX |
|
Number of registers (LSB) |
0x71 |
Value of register 12001 (MSB) |
0xXX |
|
CRC (MSB) |
0xXX |
Value of register 12001 (LSB) |
0xXX |
|
CRC (LSB) |
0xXX |
– |
0xXX |
|
– |
– |
– |
0xXX |
|
– |
– |
Value of register 12112 (MSB) |
0xXX |
|
– |
– |
Value of register 12112 (LSB) |
0xXX |
|
– |
– |
CRC (MSB) |
0xXX |
|
– |
– |
CRC (LSB) |
0xXX |