Sifam Tinsley Theta 30P, Руководство по эксплуатации

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4.1 Accessing 3 X register for reading measured values:
Two consecutive 16 bit registers represent one parameter. Refer
table 2 for the addresses of 3X registers (Parameters measured by
the instruments).
Each parameter is held in the 3X registers. Modbus Code 04 is used
to access all parameters.
Example :
To read parameter,
Active power sum : Start address= 34 (Hex) Number of registers = 02
Note : Number of registers = Number of parameters x 2
Each Query for reading the data must be restricted to 20
parameters or less. Exceeding the 20 parameter limit will cause a
Modbus exception code to be returned.
Query :
Device
Address Function
Code
Start Address
High Start Address
Low
Number of
Registers Hi Number of
Registers Lo
01 (Hex) 04 (Hex) 00 (Hex) 34(Hex) 00 (Hex) 02(Hex) 30 (Hex)
CRC
Low CRC
High
05 (Hex)
Response: Active Power Sum (4331 W)
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.
(Note : Two consecutive 16 bit register represent one parameter. )
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