Description Of Communication Protocol 217
V560 Series High Performance Closed-Loop Vector Inverter User manual
11. DESCRIPTION OF COMMUNICATION
PROTOCOL
11.1 MODBUS PROTOCOL DESCRIPTION
11.1.1 PROTOCOL OVERVIEW
Modbus protocol is a universal protocol used in the industrial control unit. Because this protocol can be
conveniently applied, this protocol has been considered as the general industry standard and is widely
applied to the integrated system of master controllers and slave units. By applying this protocol, units of
various brands can be connected together and functioning as an industrial network.
Modbus defines three types of transmission modes: ASCII, RTU and TCP. V560 Frequency inverter only
supports RTU mode.
11.1.2 INTERFACE AND TRANSMISSION METHOD
V560 utilizes RS485 (RS232, optional, which has to be converted by a level) as the physical interface for
Modbus, and one host can control one or more (maximum 247 units) frequency inverters.
Terminal Identifier Terminal Usage Function
RS+
Data Transceiving
Terminal(+)
When connected to PC/PLC via RS 485 communication
interface, connect to (+) signal
RS-
Data Transceiving
Terminal(-)
When connected to PC/PLC via RS 485 communication
interface, connect to (-) signal
By applying the asynchronous serial half-duplex transmission method, only master unit or slave unit can
transmit data at one particular moment, and the other unit can only receive data.
11.1.3 DATA STRUCTURE
1) 4 Optional Data Transmission Formats
1 start bit, 8 data bits, 1 stop bit, without parity bit (factory setting)
1 start bit, 8 data bits, 1 stop bit, even parity
1 start bit, 8 data bits, 1 stop bit, odd parity
1 start bit, 8 data bits, 2 stop bit, without parity bit
2) Baud rate
Seven optional baud rates: 1200bps, 2400 bps, 4800 bps, 9600 bps, 19200 bps, 38400bps, 79600 bps
3) Communication rules
Starting interval between data frames is longer than 3.5 byte transmission cycle (standard), but the
minimum interval should not be shorter than 0.5 ms.
11.1.4 PARAMETER CONFIGURATION FOR FREQUENCY INVERTERS
FA.0.00 is a read-only parameter, and is used to display the status of the communication card connection
and bus;
FA.0.01 = 00XX, unit digit is used to choose baud rate, and tens digit is used to choose data format;
FA.0.02 = X, choose the address of this station;
FA.0.03~FA.0.06, configure supporting communication parameters; refer to functional parameter table for
detailed functions.
¾ X indicates that this digit can be any value in the allowed range.
To Next Page
Loading...
Need help?
General
