INVT GD10-0R2G-2-B, Руководство по эксплуатации

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Goodrive10 Series Mini VFD Communication protocol
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uses a twisted pair, in which one wire is defined as A (+), and the other B (-). Generally, if the
positive electrical level between the transmission drives A and B ranges from +2 V to +6 V,
the logic is "1"; and if it ranges from -2 V to -6 V, the logic is "0".
On the VFD terminal block, the 485+ terminal corresponds to A, and 485- corresponds to B.
The communication baud rate (P14.01) indicates the number of bits sent in a second, and
the unit is bit/s (bps). A higher baud rate indicates faster transmission and poorer
anti-interference capability. When a twisted pair of 0.56mm (24 AWG) is used, the maximum
transmission distance varies according to the baud rate, as described in the following table.
Baud
rate
Max.
transmission
distance
Baud
rate
Max.
transmission
distance
Baud
rate
Max.
transmission
distance
Baud
rate
Max.
transmission
distance
2400
BPS
1800m
4800
BPS
1200m
9600
BPS
800m
19200
BPS
600m
When RS485 interfaces are used for long-distance communication, it is recommended that
you use shielded cables, and use the shielding layer as the ground wires.
When there are fewer devices and the transmission distance is short, the whole network
works well without terminal load resistors. The performance, however, degrades as the
distance increases.
Therefore, it is recommended that you use a 120Ω terminal resistor
when the transmission distance is long.I
7.2.1.1 When one VFD is used
Figure 7-1 is the Modbus wiring diagram for the network with one VFD and PC. Generally,
PCs do not provide RS485 interfaces, and therefore you need to convert an RS232 or USB
interface of a PC to an RS485 interface through a converter. Then, connect end A of the
RS485 interface to the 485+ port on the terminal block of the VFD, and connect end B to the
485- port. It is recommended that you use shielded twisted pairs. When an RS232-RS485
converter is used, the cable used to connect the RS232 interface of the PC and the
converter cannot be longer than 15 m. Use a short cable when possible. It is recommended
that you insert the converter directly into the PC. Similarly, when a USB-RS485 converter is
used, use a short cable when possible.
When the wiring is completed, select the correct port (for example, COM1 to connect to the
RS232-RS485 converter) for the upper computer of the PC, and keep the settings of basic
parameters such as communication baud rate and data check bit consistent with those of
the VFD.Select