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Energy Box AC-Α, AC
37
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3. Physical Connection
Communication
network is showed below. Control board can be connected to RS485 on
which is connected more than one unit.Address conflicts on this line should be removed and
necessary software settings should be done for data communication.
DI
D
D
DI
DI
DE
DE
DE
DI
RO
RO
RO
D
D
R
R
RR
A
B
BB
B
A
AA
DE
RO
MAX4
8
1
MAX483
MAX485
MAX487
MAX1487
RE
RE
RE
RE
Fig. 2,1 RS485 Wiring Example
If the line is too long or if any communication problem occurs, 120 Ohm resistance should
be added at the beginning and end of the line as shown on schema.
4. Modbus Functions
Communication package
(Table 3,1)
is the same for each function. First address
information of relevant module is sent on package.
Table 3,1
Modbus package type
Address Information
Function Code
Data
Failure Control (CRC16)
Control board supports only two of standard functions of Modbus. These codes are 03 register
reading
(Table 3,2)
and 06 register writing
(Table 3,3)
. In the example below
(Table 3,2)
, master
wants to know the 16 bit data on 2nd register. Corresponding response value of control board is
shown on the table below. In the second example
(Table 3,3)
, master wants to write the 16 bit data
on 2nd register and it is reported to control board that the data was written.
Summary of Contents for ENERGY BOX AC
Page 43: ......
