Invt CHV190-045G-4 [151/242] Protocol function

CHV190 series special inverter for crane

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Node adds.

Command Data adds. Read No. CRC

0x01 0x03 0x00

0x02

0x00

0x01

0x25 0xCA

The table below shows the reply frame from slave node address 1.

Node adds.

Command Bytes No. Data CRC

0x01 0x03 0x02 0x00

0x00

0xB8 0x44

ASCII mode

In ASCII mode, the frame head is “0x3A”, and default frame tail is “0x0D” or “0x0A”. The

frame tail can also be configured by users. Except frame head and tail, other bytes will be

sent as two ASCII characters, first sending higher nibble and then lower nibble. The data

have 7/8 bits. “A”~“F” corresponds to the ASCII code of respective capital letter. LRC

check is used. LRC is calculated by adding all the successive bytes of the message

except the head and tail, discarding any carriers, and then two’s complementing the result.

Example of Modbus data frame in ASCII mode:

The command frame of writing 0x0003 into address “0x1000” of slave node address 1 is

shown in the table below:

LRC checksum = the complement of (01+06+10+00+0x00+0x03) = 0xE5.

Frame head

Node adds.

Command Data adds.

Code 0 1 0 6 1 0 0 0

ASCII 3A 30 31 30 36 31

Data to write LRC Frame tail

0 0 0 3 E 5 CR LF

30 30 30 33 45 35 0D 0A

10.4 Protocol Function

Different respond delay can be set through drive’s parameters to adapt to different needs.

For RTU mode, the respond delay should be no less than 3.5 bytes interval, and for ASCII

mode, no less than 1ms.

The main function of Modbus is to read and write parameters. The Modbus protocol

supports the following commands:

0x03 Read inverter’s function parameter and status parameters

0x06 Write single function parameter or command parameter to inverter

All drive’s function parameters, control and status parameters are mapped to Modbus R/W

data address.