INVT GD20-004G-2-EU, Руководство по эксплуатации

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Goodrive20-EU series VFD Communication protocol
115
Twisted pairs with shied screen
Earth
Earth
Computer
RS485 Rout
Convert from
RS232 to RS485
485- 485+
VFD
Figure 7-1 RS485 physical connection in single application
7.2.1.2 Multi-applications
In real multi-applications, 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 120
Ω which is shown as figure 2.
VFD VFD VFD
Address 1
Address n
Earth
485
+
485
-
Earth
485
+
485
-
Earth
485
+
485
-
120 Ohm
Terminal resistor
Computer
Conv
ertor
GND
RS232-485
Max length of
RS: 15m
.
Twisted pair cables with shield screen
Address 2
Figure 7-2 Chrysanthemum connection applications
Figure 3 is the star connection. Terminal resistor should be connected to the two devices
which have the longest distance. (1# and 15#device)
1
#
15
#
32
#
6
#
Main control
devices
Figure 7-3 Star connection