Viewse VC-EX861, Инструкция по установке и эксплуатации

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The maximum load capacity is 32 unit loads (including main
controller and controlled equipment).
2. Transmission distances of RS485 Bus
When user selects the 0.56mm (24AWG) twisted pair wires as data
transmission cable, the maximum theoretical transmitting distances
are as follows:
Baud Rate Maximum Transmitting
Distance
2400 Bps 1800m
4800 Bps 1200m
9600Bps 800m
Table 7
If user selects thinner cables, or installs the dome in an
environment with strong electromagnetic interference, or connects
lots of equipment to the RS485 Bus, the maximum transmitting
distance will be decreased. To increase the maximum transmitting
distance, do the contrary.
3. Connection and termination resistor
The RS485 standards require a daisy-chain connection between
the equipment. There must be termination resistors with
120
Ω
impedance at both ends of the connection (refer to Picture
32). Please refer to Picture 33 for simple connection. “D” should
not exceed 7m.
120 Ω 120 Ω
1# 2# 3# 4# 32#
. . . . .
Figure 32
-32323232 32