Lumel ND25 - Page 8

Note : Number of registers = Number of parameters x 2
Each Query for reading the data must be restricted to 40 parameters or less. Exceeding the 40 parameter
limit will cause a ModBus exception code to be returned.
Device
Address
Function
Code
Start Address
High
Start Address
Low
Number of
Registers Hi
Number of
Registers Lo
CRC
Low
CRC
High
01 (Hex)
04 (Hex)
00 (Hex)
02(Hex) 00 (Hex)
02(Hex) 30 (Hex) 0A (Hex)
Query for 3X read:
3X Response: Voltage 2 (219.254V)
Device
Address
Function
Code
Byte
Count
Data Register1
High Byte
CRC
High
01 (Hex)
04 (Hex)
04 (Hex)
43 (Hex) 5B (Hex)
41 (Hex) 21 (Hex) 6F (Hex)
Data Register1
Low Byte
Data Register2
High Byte
Data Register2
Low Byte
9B (Hex)
CRC
Low
Byte Count : Total number of data bytes received.
Query for 4X read:
Device
Address
Function
Code
Start Address
High
Start Address
Low
Number of
Registers Hi
Number of
Registers Lo
CRC
Low
CRC
High
01 (Hex) 03 (Hex) 00 (Hex) 0E(Hex) 00 (Hex) 02(Hex) E0 (Hex) C9 (Hex)
4X Response: Watt2 (2000 W)
Device
Address
Function
Code
Byte
Count
Data Register1
High Byte
CRC
High
01 (Hex) 03 (Hex) 04 (Hex) 44 (Hex) FA (Hex) 00 (Hex) 00 (Hex) CE (Hex)
Data Register1
Low Byte
Data Register2
High Byte
Data Register2
Low Byte
F2 (Hex)
CRC
Low
Start Address High : Most significant 8 bits of starting address of the parameter requested.
Start Address low : Least significant 8 bits of starting address of the parameter requested.
Number of register Hi : Most significant 8 bits of Number of registers requested.
Number of register Lo : Least significant 8 bits of Number of registers requested.
Data register 1 High Byte : Most significant 8 bits of Data register 1 of the parameter requested.
Data register 1 Low Byte : Least significant 8 bits of Data register 1 of the parameter requested.
Data register 2 High Byte : Most significant 8 bits of Data register 2 of the parameter requested.
Data register 2 Low Byte : Least significant 8 bits of Data register 2 of the parameter requested.
(Note : Two consecutive 16 bit register represent one parameter.)
Byte count : No.of Bytes Demanded by user in querry.
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