Circutor CVM-E3-MINI - MODBUS PROTOCOL

7.2.- MODBUS PROTOCOL
In the Modbus protocol, the CVM-E3-MINI device uses the RTU (Remote Terminal Unit) mode.
The Modbus functions implemented in the device are as follows:
Function 0x03 and 0x04. Reading integer registers.
Function 0x05. Writing a relay.
Function 0x10. Writing multiple registers.
7.2.1.- READING EXAMPLE : Funtion 0x04.
Question: Instantaneous value of the phase voltage of L1
Address Function
Initial
register
No. of
registers
CRC
0A 04 0000 0002 70B0
Address: 0A, Peripheral number: 10 in decimals.
Function: 04, Read function.
Initial Register: 0000, register on which the reading will start.
No. of registers: 0002, number of registers read.
CRC: 70B0, CRC Character.
Response:
Address Function No. of Bytes Register No. 1 Register No. 2 CRC
0A 04 04 0000 084D 8621
Address: 0A, Responding peripheral number: 10 in decimals.
Function: 04, Read function.
No. of bytes: 04, No. of bytes received.
Register: 0000084D, value of the phase voltage of L1: VL1 x 10 : 212.5V
CRC: 8621, CRC Character.
Note: Every Modbus frame has a maximum limit of 20 variables (40 logs).
7.2.2.- WRITING EXAMPLE : Funtion 0x05.
Question: Deleting maximum and minimum values.
Address Function
Initial
Register
Value CRC
0A 05 0834 FF00 CEEF
Address: 0A, Peripheral number: 10 in decimal.
Function: 05, Read function.
Initial register: 0834, register of the parameter for deleting maximum and minimum values.
Value: FF00, we indicate that we want to delete the maximum and minimum values.
CRC: CEEF, CRC character.
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Instruction Manual
CVM-E3-MINI