VTS Medical Systems VTS2000 Series, User Manual

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VTS2000 Series frequency inverter
- 80 -
selection After the asynchronous motor is loaded, it
will cause the speed to drop. The use of slip
compensation can make the motor speed
close to its synchronous speed, so that the
motor speed control accuracy is higher.
7 Communication Protocol
(The following data are all hexadecimal)
1
、
RTU mode and format
When the controller communicates on the Modbus bus in RTU mode, each 8-bit byte in the information is divided into
two 4-bit hexadecimal characters. The main advantage of this mode is that the density of characters transmitted is higher
than that of ASCII mode at the same baud rate, each message must be transmitted continuously.
（
1
）
The format of each byte in RTU mode
Coding system: 8-bit binary, hex 0-9, A-F.
Data bits: 1 start bit, 8 bits of data (lowest bit sent first), 1 stop bit, parity bit can be selected. (Refer to RTU data
frame bit sequence diagram)
Error check area: cyclic redundancy check (CRC).
（
2
）
RTU data frame bit sequence diagram