Circutor RGU-10 - MODBUS PROTOCOL; READ EXAMPLE: Function 0 x04.

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Instruction Manual
RGU-10, RGU-10C
6.2.- MODBUS PROTOCOL
In the Modbus protocol, the RGU-10C uses the RTU (Remote Terminal Unit) mode.
The Modbus functions implemented in the device are as follows:
Function 0x04: Reading integer registers.
Function 0x10: Writing multiple registers.
6�2�1� READ EXAMPLE: Function 0x04�
Query:
Address Function
Initial
Register
No� of
registers
CRC
0A 04 0000 000A 7176
Address: 0A, Peripheral number: 10 in decimal.
Function: 04, Read function.
Initial Register:0000, register from which to start reading.
No� of Registers: 000A, number of registers to be read: 10 in decimal.
CRC: 7176, CRC character.
Response:
Address Function
No� of
Bytes
Registers
CRC
nº 1 nº 2 nº 3 nº 4 nº 5 nº 6 nº 7 nº 8 nº 9 nº 10
0A 04 14 000A 0002 0000 0032 0000 0001 0000 0001 0014 0000 7EC9
Address: 0A, Responding peripheral number: 10 in decimal.
Function: 04, Read function.
No� of bytes: 14, No. of bytes received: 20 in decimal.
Registers: 000A, Address 0000h: Peripheral number : 10
0002, Address 00001h: Baud rate : 2 = 9600 bds
0000, Address 00002h: Type of parity : 0 = None
0032, Address 00003h: Operating frequency : 50 Hz
0000, Address 00004h: Trip current : 0 = 30 mA
0001, Address 00005h: Time for trip delay : 1 = INS
0000, Address 00006h: Relay output trip polarity : 0 = Standard
0001, Address00007h:%I∆ntripbypre-alarm.:1=50%
0014, Address 00008h: Time for pre-alarm delay: 1 = 20ms
0000, Address 00009h: Pre-alarm output relay polarity : 0 = Standard
CRC: 7EC9, CRC character.
Note : Each Modbus frame has a maximum limit of 26 registers.