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maximum theoretical transmitting distances are as follows according to different baud rate:
If user selects thinner cables, or installs the dome in an environment with strong
electromagnetic interference, or connects lots of equipment to the RS 485 Bus, the maximum
transmitting distance will be decreased. To increase the maxim um transmitting distance, do
the contrary
Baud Rate
Maximum Distance
2400 bps
1800m
4800 bps
1200m
9600bps 800m
19200bps 600m
* Connection and terminal resistance
The RS485 standards require a daisy-chain connection between the equipment. There
must be termination resistance wit h 120
Ω
at both ends of the connection (refer to picture
4-1.1).
Please refer to picture4-1.2 for simple connection. And “D” should not exceed 7m.
Picture4-1.1
