Goodrive350 IP55 High-ingress Protection Series VFD
Communication protocol
-286-
Code
Name
Definition
08H
Parameter
cannot be
modified in
running
The parameter to be modified in the write operation of the upper
computer cannot be modified during the running of the VFD.
09H
Password
protection
A user password is set, and the upper computer does not provide the
password to unlock the system when performing a read or write
operation. The error of "system locked" is reported.
When returning a response, the device uses a function code domain and fault address to
indicate whether it is a normal response (no error) or exception response (some errors occur).
In a normal response, the device returns the corresponding function code and data address or
sub-function code. In an exception response, the device returns a code that is equal to a
normal code, but the first bit is logic 1.
For example, if the master device transmits a request message to a slave device for reading a
group of function code address data, the code is generated as follows:
0 0 0 0 0 0 1 1 (03H in the hexadecimal form)
For a normal response, the same code is returned.
For an exception response, the following code is returned:
1 0 0 0 0 0 1 1 (83H in the hexadecimal form)
In addition to the modification of the code, the slave returns a byte of exception code that
describes the cause of the exception. After receiving the exception response, the typical
processing of the master device is to transmit the request message again or modify the
command based on the fault information.
For example, to set the "Running command channel" (P00.01, the parameter address is
0001H) of the VFD whose address is 01H to 03, the command is as follows:
VFD
address
Write
command
Parameter
address
Parameter
data
CRC
01
06
00 01
00 03
98 0B
But the setting range of the "Running command channel" is 0 to 2. The value 3 exceeds the
setting range. In this case, the VFD returns an error message response as shown in the
following:
VFD
address
CRC
Error code
Exception
response code
01
86
04
43 A3
The exception response code 86H (generated based on the MSB "1" of the write command
06H) indicates that it is an exception response to the write command (06H). The error code is
04H. From the preceding table, we can see that it indicates the error "Operation failure", which
means "The parameter is set to an invalid value in the write operation".
9.4.8 Read/Write operation example
For the formats of the read and write commands, see sections 9.4.1 and 9.4.2.
