FOTEK GD20-004G-2, Руководство по эксплуатации

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Goodrive20 Series VFD Communication protocol
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times into 5012, so hex 1394H can be used to express 50.12.
A non-integer can be timed by a multiple to get an integer and the integer can be called
fieldbus ratio values.
The fieldbus ratio values are referred to the radix point of the setting range or default value in
the function parameter list. If there are figures behind the radix point (n=1), then the fieldbus
ratio value m is 10
n
. Take the table as the example:
Function
code
Name Description Default Modify
P01.20
Wake-up-from-slee
p delay
0.0
–3600.0s (valid when P01.19
is
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
Parameters
address
Data number CRC check
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 command, the master receives the following response from the VFD:
VFD
address
Read
command
Parameters
data
CRC check 2-byte
data
The parameter data is 0032H, that is, 50, so 5.0 is obtained based on the fieldbus scale
(50/10=5.0). In this case, the master identifies that the "Wake-up-from-sleep delay" is 5.0s.
7.4.4 Error message response
Operation errors may occur in communication-based control. For example, some parameters
can only be read, but a write command is transmitted. In this case, the VFD returns an error
message response. Error message responses are sent from the VFD to the master. The
following table describes the codes and definitions of the error message responses.