Hitachi SJ700-4000HFU2

Chapter 4 Explanation of Functions
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The formats of the query and response frames are described below.
Message configuration: Query
Header (silent interval)
Slave address
Function code
Data
Error check code
Trailer (silent interval)
(i) Slave address
The slave address is a number 1 to 32 that is assigned to the inverter (slave) beforehand. (A query is received by
the inverter having the same slave address as that specified in the query.)
The query with the slave address set to "0" is broadcasted to all the connected inverters.
With a broadcast query, the master system can neither read inverter data nor perform a loopback test.
(ii) Data
The data contains a functional instruction.
The SJ700 series inverter supports the following Modbus data format:
Data name
Description
Coil data
1-bit binary data that can be referenced and changed
Register data
16-bit data that can be referenced and changed
(iii) Function code
The function code specifies the function to be executed by the inverter.
The table below lists the function codes supported by the SJ700 series inverter.
Function codes
Function code
Function
Maximum number of data bytes
in a message
Maximum data count in a
message
01h
Reads the coil status.
4
32 coils (in units of bit)
03h
Reads registers.
8
4 registers (in units of byte)
05h
Writes data to a coil.
2
1 coil (in units of bit)
06h
Writes data to a register.
2
1 register (in units of byte)
08h
Performs a loopback test.
-
0Fh
Writes data to multiple coils.
4
32 coils (in units of bit)
10h
Writes data to multiple registers.
8
4 registers (in units of byte)