3.0—Home Security and Surveillance Systems

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Chapter
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detectors, smoke and fire sensors, cameras, camera switchers, video displays,
and sirens. The advantages for a hard-wired security system are
➤ Hard-wired security systems are considered by most contractors to be
more reliable than wireless systems.
➤ Hard-wired systems are usually installed by a professional security system
contractor with warranties and maintenance support.
➤ Hard-wired systems avoid the problem of EMI and radio range limitations
inherent in some wireless security systems.
➤ The hard-wired components are usually less visible and more aesthetically
pleasing than wireless components.
➤ Hard-wired systems do not depend on batteries except for power failure
backup protection.
The disadvantages of a hard-wired security system are
➤ Hard-wired systems are more expensive than wireless systems.
➤ Hard-wired systems are usually leased from the company that installs
the system. Unlike a wireless system, the hard-wired system remains an
integral part of the home. The components are not capable of being
moved to another home when the owner relocates.
➤ Problems can arise in the installation of sensors in existing homes where
some areas are not accessible for pulling wires inside the walls.
Remote Access Systems
A remote access system provides the capability to monitor and control a home
security system from a location away from the home. A telephone call to the
home followed by a key number code allows the caller to obtain status information
concerning environmental and alarm system condition. Remote systems
can also be programmed to call a specific phone number when certain
environmental conditions exceed an established threshold. A special synthesized
voice response system provides the caller with an audible report. The
caller, with proper coded inputs, can also perform all the same control functions
from a distant location that are available on the keypad in the home.
Features of remote access systems vary among vendors, but most systems
have features similar to those listed here:
➤ Monitoring and reporting temperature inside and outside the home
➤ Reporting on any sensors that have exceeded preset thresholds