COP-USA CD55-H-SDI - Manual (Page 27)

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Appendix : The Cleaning of Clear Down Cover
To obtain constant clear videos, user should clean the down cover periodically.

Be cautious when cleaning. Hold the down cover ring only to avoid direct touch to the
acrylic down cover. The acid sweat mark of fingerprint will corrode the coating of
down cover and scratch on down cover will cause vague images.
 Use soft dry cloth or the substitute to clean the inner and outer surfaces.
 For hard contamination, use neutral detergent. Any cleanser for high grade furniture
is applicable.
Appendix III: RS485 Bus Basic Knowledge
1. Characteristics of RS485 Bus
As specified by RS485 standards, RS485 Bus is of half-duplex data transmission
cables with characteristic impedance as 120Ω. 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
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 120Ωimpedance at both ends of the connection
(refer to Figure 20).
Please refer to Figure 21 for simple connection. “D” should not exceed 7m.
120Ω 120Ω
1# 2# 3# 4# 32#
. . . . .
Figure 20