IMO SD1 Series - Page 141

SD1 Series Inverters Communication Protocol
-136-
Code
Name
Meaning
cannot be
modified in
running
upper computer cannot be modified during the running of the
inverter.
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 inverter 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.
When the master receives the response for the objection, in a typical processing, it will send
the message again or modify the corresponding order.
For example, set the "running command channel" of the inverter (P00.01, parameter address
is 0001H) with the address of 01H to 03, the command is as following:
VFD
address
Write
command
Parameters
address
Parameters
data
CRC check
But the setting range of "running command channel" is 0~2, if it is set to 3, because the
number is beyond the range, the inverter will return fault response message as below:
VFD
address
CRC check Fault code
Abnormal
response code
Abnormal response code 86H means the abnormal response to writing command 06H; the
fault code is 04H. In the table above, its name is operation failed and its meaning is that the
parameter setting in parameter writing is invalid. For example, the function input terminal
cannot be set repeatedly.