DRV-28 inverter
s Communication protocol
-271-
"Wake-up-from-sleep delay" of the inverter 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:
Inverter
address
Write
command
Parameter
address
Parameter
data
CRC
01
06
01 14 00 32
49 E7
After receiving the command, the inverter 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 inverter:
Inverter
address
Read
command
Parameter
data
CRC
2-byte
data
01
03
02
00 32
39 91
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.
9.4.7 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 inverter returns an error message
response.
Error message responses are transmitted by the inverter to the master. The following table describes
the codes and definitions of the error message responses.
Code
Name
Definition
01H
Invalid
command
The command code received by the upper computer is not allowed
to be executed. The possible causes are as follows:
• The function code is applicable only on new devices and is not
implemented on this device.
• The slave is in the faulty state when processing this request.
02H
Invalid data
address
For the inverter, the data address in the request of the upper
computer is not allowed. In particular, the combination of the
register address and the number of the to-be-transmitted bytes is
invalid.
03H
Invalid data bit
The received data domain contains a value that is not allowed. The
value indicates the error of the remaining structure in the combined
request.
Note:
It does not mean that the data item submitted for storage in
