Goodrive600 series high-performance multifunction VFD
Communication networking
-128-
The Read/Write (R/W) characteristics indicate whether a function can be read and written. For example,
"Communication-based control command" can be written, and therefore the command code 06H is used to control the
VFD. The R characteristic indicates that a function can only be read, and W indicates that a function can only be written.
Note:
Some parameters in the preceding table are valid only after they are enabled. Take the running and stop
operations as examples, you need to set "Running command channel" (P00.01) to "Communication", and set
"Communication running command channel" (P00.02) to the Modbus communication channel. For another
example, when modifying "PID setting", you need to set "PID reference source" (P09.00) to Modbus
communication.
The following table describes the encoding rules of device codes (corresponding to the identification code 2103H of the
VFD).
Eight
high-order bits
of code
Meaning
Eight low-order
bits of code
Meaning
01
GD
0x01B1
GD600 rectifier unit
0x01B2
GD600 inverter unit
6.3.5 Fieldbus scale
In practical applications, communication data is represented in the hexadecimal form, but hexadecimal values cannot
represent decimals. For example, 50.12 Hz cannot be represented in the hexadecimal form. In such cases, we can
multiply 50.12 by 100 to obtain an integer 5012, and then 50.12 can be represented as 1394H (5012 in the decimal form)
in the hexadecimal form.
In the process of multiplying a non-integer by a multiple to obtain an integer, the multiple is referred to as a fieldbus scale.
The fieldbus scale depends on the number of decimals in the value specified in "Setting range" or "Default". If there are
n
decimals in the value, the fieldbus scale m is the
n
th
-power of 10. Take the following table as an example, m is 10.
Function
code
Name
Description
Default
P01.20
Wake-up-from-sleep delay
0.0
–3600.0s (Valid when P01.19=2)
0.0s
P01.21
Power-off restart selection
0: Disable
1: Enable
0
The value specified in "Setting range" or "Default" contains one decimal, so the fieldbus scale is 10. If the value received
by the upper computer is 50, the value of "Wake-up-from-sleep delay" of the VFD is 5.0 (5.0=50/10).
To set the "Wake-up-from-sleep delay" to 5.0s through Modbus communication, you need first to multiply 5.0 by 10
according to the scale to obtain an integer 50, that is, 32H in the hexadecimal form, and then transmit the following write
command:
VFD
address
Write
command
Parameter
address
Parameter
data
CRC
01
06
01 14 00 32
49 E7
After receiving the command, the VFD converts 50 into 5.0 based on the fieldbus scale, and then sets
"Wake-up-from-sleep delay" to 5.0s.
For another example, after the upper computer transmits the "Wake-up-from-sleep delay" parameter read command, the
master receives the following response from the VFD:
