6. Appendix
6.1 Transmission distance
：
When a 0.56mm (24AWG) twisted pair cable is used as the communication cable, the theoretical value of the
maximum transmission distance varies with different baud rate settings:
2400bps: 5900ft (1800m)
19200bps: 1960ft (600m)
When using a thinner communication cable, or when the product is used in an environment with strong
electromagnetic interference, or when too many devices are connected to the same controller, the maximum
transmission distance will be shortened accordingly.
6.2 Connection method and terminating resistor
RS485 industrial bus standard requires daisy chain connections between devices. The two ends must be connected
with a 120Ω termination resistor, and the balance distance must be within22ft (7m).
6.3 Applications
A star link is in most real cases used when there is a switcher/router, requiring a terminating resistor to be used on
the two devices on both ends. However, it does not meet the RS485 industry standards. When the distance between
each device are too long, signal reflection and anti-interference ability is like to reduce, and will decrease the
reliability of the control signal. It means the camera will not be responsive as expected. In this case, RS485 is
recommended, so that you may convert the star link mode to RS485 industry standard. It will help avoid connection
issues and improve the communication reliability.
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