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Controller
Problems in the practical application - star-shaped architecture
Although the star-shape connection method is commonly used, it does not satisfy the requirement of the RS-485 industry. This
architecture can lead to problems such as signal reflection, uncontrollable or self-running cameras, and anti-jamming inability with
devices that are far away. In the star-shaped connection, the termination resistors are usually placed in the two devices that are
farthest apart (see figures below).
Signal transmission in the star-shaped architecture can be greatly improved by adding an RS-485 distributor. This product
effectively changes the star-shape connection to one that satisfies the requirement of the RS-485 industry standard. See the
diagram below.
A+
B–
A+
B–
#1
RS-485 Connection 2 diagram
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#1
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Star-shaped connection
APPENDIX B: RS-485 BUS CONNECTION
#2
#3
Controller
#15
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36x PTZ Dome Camera User Manual
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#31
#6
45
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