INVT GD270-030-4 - Page 278

Goodrive270 series VFD for fan and pump Communication
-268-
According to the requirements of the RS485 industrial bus standards, all the devices need to be
FRQQHFWHGLQFKU\VDQWKHPXPPRGHZLWKRQHȍWHUPLQDOUHVLVWRURQHDFKHQGDVVKRZQLQFigure
9-2. Figure 9-3 is the simplified wiring diagram, and Figure 9-4 is the practical application diagram.
1 # 2
#
3 # 4 # 32 #
120¡
120¡
Figure 9-2 Onsite chrysanthemum connection diagram
1# 2# 3# 31#Master
A+
B-
A+ B-
Figure 9-3 Simplified chrysanthemum connection diagram
INVT
VFD
Address 1
Earth
485+
485-
485+
485 -
485+
485-
120œ
Terminal resistor
PC
Converter
GND
RS232-RS485
Max. length of the
cable: 15 m
Shielded twisted pair
Address 2 Address N
INVT
VFD
INVT
VFD
Earth Earth
Figure 9-4 Practical application diagram of chrysanthemum connection
Figure 9±5 shows the start connection diagram. When this connection mode is adopted, the two
devices that are farthest away from each other on the line must be connected with a terminal resistor
(the two devices are devices #1 and #15).