CHINT NVF2G-S Series - Page 75

Table 9.1 Modbus command code and usage
command code
use
0x03
Read inverter parameters, including function code parameters, control parameters and status
parameters
0x04
Read the drive parameter attribute value.
0x06
Rewrite a single 16 -bit inverter function code parameter or control parameter.
0x10
Rewrite multiple inverter function codes or control parameters.
9.5.2 Inverter function parameter address mapping rules
The group number of the inverter function parameter is mapped to the high byte of the Modbus register
address ( 0~F corresponds to the value 0x00~0x0F ), and the group index (that is, the serial number of the
parameter in the group) is mapped to the low byte of the Modbus register address (00 ~99 corresponds to
0x00~0x63) , when the data only needs to be saved in RAM (that is, the data will not be saved after power
failure), set the highest bit of the address to "1" . For example: modifying the frequency value by communication
can be realized by modifying the function parameter F0.05 .
The register address corresponding to the function parameter " F0.05 " (digital setting frequency value) is
" 0x0005 ":
1) When the data is only stored in RAM , the corresponding address is "0x8005" .
2) When the data needs to be saved to EEPROM (save data after power failure), the corresponding address
is " 0x0005 ".
Remark:
When the set frequency needs to be modified frequently and the parameter does not need to be saved
after power-off, it is recommended to use the first method, that is, only save to RAM, which can prolong the
service life of EEPROM.
9.5.3 Get the parameter attribute of the inverter function code
The parameter attribute corresponding to the function code parameter of the inverter can be obtained
through the 0x04 command code, and the attribute definition format is shown in Table 9.2 .
Table 9.2 Data format definition when reading parameter properties
Table 9.3 Definition of parameter attribute value bit ( bit )
data byte sequence number
meaning
1
Maximum value ( high byte )
2
Maximum value ( low byte )
3
Minimum value ( high byte )
4
Minimum value ( low byte )
5
Current value ( high byte )
6
Current value value ( low byte )
7
Parameter attribute value (high byte), refer to Table 9.3
8
Parameter attribute value (low byte), refer to Table 9.3
bit definition
bit value decimal value
meaning
15~14bit: display type
00 0
decimal
01
1
hexadecimal display
10
2
binary display
13~11bit: Modify attributes
000 0
read and write anytime
001
1
Can only be modified in the shutdown state
010
2
read-only parameter
011
3
Enterprise password is required to read and write
100
4
Requires corporate password to read
101
5
Requires user password to read and write
067
NVF2G-S Series Inverter User's Guide