Unitronics UMI-B1 UL Series Operation Manual page 132

UMI-B1 UL Series Inverter Communication protocol
Continuous Parameters
Inverter Byte
Data 10s 20s
CRC check
writing
address
address number
number
command
If the response message is as below:
Inverter Continuous
Parameters
Data
CRC check
writing
address
address
number
command
Note: The space between above commands is for instruction and there is no space
between the commands during actual applications.
Common communication fault
Common communication faults: no response to the communication or the inverter
returns abnormal fault.
The possible reason for no response to the communication:
A wrong serial interface is selected, for example, the converter is COM1, but COM2 is
selected during the communication.
The baud rate, digital bit, end bit and check bit are not the same with the inverter + and -
of RS485 are connected in reverse.
The 485 wire cap on the terminal board of the inverter is not plug in. the wire cap in
behind the terminal arrangement.
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