ADEMCO RapidEye plus, Инструкция по установке и настройке

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Rapid Eye Remote Video Unit Installation and Setup Guide
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Appendix C: Common CCTV Practices
C.2.3 Coaxial Cable Checklist
The following checklist indicates items that must be considered when
designing and installing a CCTV system.
•
Terminate all unused inputs and unused outputs in their correct
impedance.
•
When calculating coaxial cable attenuation, use the highest
frequency you expect to transmit in the cable.
•
In long cable runs, use the minimum possible number of connectors.
(Each connector causes attenuation.)
•
Do not splice coaxial cables without the use of proper connectors.
(This can cause reflection of the signal, resulting in distortion.)
•
For outdoor applications, ensure all connectors are weatherproof.
•
If unbalanced coaxial cable runs exist between low power sources,
use fiber optic cable to avoid ground loop problems.
•
In long transmission systems, use balanced coaxial cable (or fiber
optic cable).
•
Do not run coaxial cable adjacent to high-power RF sources such as
power lines.
C.3 Potential Problems
The following problems are most likely to occur in indoor or outdoor coaxial
cable installations:
•
Different ground potentials at the ends of the coaxial cable, or at
different TV equipment locations in a building.
•
Coaxial cable running through or close to electrical equipment. The EMI
fields produced can distort the signal.
•
Environmental conditions such as thunderstorms or lightning storms.