CIRCUTOR CVM-C10 Series - Manual (Page 62)

4�10�2� PROTOCOL
In the Modbus protocol, the CVM-C10 unit uses the RTU (Remote Terminal Unit) mode.
The Modbus functions implemented in the unit are as follows:
0x03 and 0x04 function. Reading integer logs.
0x05 function. Writing a relay.
0x10 function. Writing multiple logs.
4�10�2�1 Ejemplo de lectura : Función 0x04�
Question: Instantaneous value of the phase voltage of L1
Address Function Initial log No� of logs CRC
0A 04 0000 0002 70B0
Address: 0A, Peripheral number: 10 in decimals.
Function: 04, Read function.
Initial Log: 0000, log on which the reading will start.
No� of logs: 0002, number of logs read.
CRC: 70B0, CRC Character.
Response:
Address
Func-
tion
No� of
Bytes
Log No� 1 Log 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.
Log: 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).
4�10�2�2� Writing example: 0x05 function.
Question: Deleting maximum and minimum values.
Address Function Initial log Value CRC
0A 05 0834 FF00 CEEF
Address: 0A, Peripheral number: 10 in decimal.
Function: 05, Read function.
Initial Log: 0834, log 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.
62
CVM-C10
Instruction Manual