INVT GD300-004G-4, Operation Manual

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Goodrive300 inverters Communication protocol
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terminal of the inverter and B to the 485- terminal. It is recommended to use the shield
twisted pairs. When applying RS232-RS485 converter, if the RS232 interface of the
computer is connected to the RS232 interface of the converter, the wire length should be as
short as possible within the length of 15m. It is recommended to connect the RS232-RS485
converter to the computer directly. If using USB-RS485 converter, the wire should be as
short as possible, too.
Select a right interface to the upper monitor of the computer (select the interface of
RS232-RS485 converter, such as COM1) after the wiring and set the basic parameters such
as communication baud rate and digital check bit to the same as the inverter.
Fig 10-1 RS485 physical connection in single application
10.3.1.2 Multi-applicationIn the real multi-application, the chrysanthemum connection and
star connection are commonly used.
Chrysanthemum chain connection is required in the RS485 industrial fieldbus standards.
The two ends are connected to terminal resistors of 120Ω which is shown as figure 2. Figure
3 is the simply connection figure and figure 4 is the real application figure.
Fig 10-2 Chrysanthemum connection