Goodrive20-UL Series VFD
Communication protocol
-130-
Code
Name
Meaning
structure in the combined request.
Note:
It does not mean that the data item submitted for
storage in the register includes a value unexpected by the
program.
04H
Operation
failure
The parameter is set to an invalid value in the write
operation. For example, a function input terminal cannot be
set repeatedly.
05H
Password
error
The password entered in the password verification address
is different from that set in P07.00.
06H
Data frame
error
The length of the data frame transmitted by the upper
computer is incorrect, or in the RTU format, the value of the
CRC check bit is inconsistent with the CRC value calculated
by the lower computer.
07H
Parameter
read-only
The parameter to be modified in the write operation of the
upper computer is a read-only parameter.
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.
The slave uses functional code fields and fault addresses to indicate it is a normal response or
some error occurs (named as objection response). For normal responses, the slave shows
corresponding function codes, digital address or sub-function codes as the response. For
objection responses, the slave returns a code which equals the normal code, but the first byte
is logic 1.
For example: when the master sends a message to the slave, requiring it to read a group of
address data of the VFD function codes, there will be following function codes:
0 0 0 0 0 0 1 1 (Hex 03H)
For normal responses, the slave responds the same codes, while for objection responses, it
will return:
1 0 0 0 0 0 1 1 (Hex 83H)
Besides the function codes modification for the objection fault, the slave will respond a byte of
abnormal code which defines the error reason.
Summary of Contents for GD20-0R4G-2-UL
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