Specifications

Example
To obtain all 3 line powers in a 4 wire system on Node 23h
Packet from master :
A sample write packet will look like this:-
[Node][1E][start address][No. of Double Registers][Data
length in bytes] [REGISTERS][CRC(2 bytes)]
It is important to remember that each register in the
packet’s data field contains two references to the registers
to be reordered.
e.g. To set the 41 Modbus registers to their default order in
node 23h:-
[23h][1Eh][23h][1Eh][0000h][002Ah][0102h][0304h][0506h][0708h]
[090Ah][0B0Ch][0D0Eh][0F10h][1112h][1314h][1516h][1718h][191Ah]
[1B1Ch][1D1Eh][1F20h][2122h][2324h][2526h][2728h][29XX]
[CRC(2bytes)]
N.B. XX = don’t care.
To read the order of the registers use code 1F (31)
eg. [23h][1F][0000][0018h][CRC(2bytes)]
40
Start at Power L1 (0020), request 3 regs (0006 words)
[23][04][0020][0006][CRC(2bytes)]
Response from slave format :
[23][04][12 bytes of data(3 regs x 4 bytes)][CRC(2 bytes)]
Function 3 (03 hex) - Reading registers (4X)
These registers contain the system setting and controls.
Register addresses in the instrument start at 0, but in
keeping with Modicon Modbus codes, are designated
addresses starting at 40001.
M550MAN.PM5 01/08/101, 12:4840