3.0—Home Security and Surveillance Systems

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Chapter
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3
Underwriters Laboratories
The Underwriters Laboratories (UL) is a nonprofit organization that has established
standards for all components of security systems and their installation. If
the product has the UL label, the device meets or exceeds UL’s requirements.
Installation Plans
Installation planning should follow the guidelines mentioned earlier in
ANSI/TIA/EIA-570A Amendment 1 and NEC articles 725 and 760.
Important requirements are summarized in this section for RJ-31x jacks,
motion detectors, and video surveillance systems.
Installing an RJ-31x Telephone Jack
A special type of telephone jack called an RJ-31x is required with all security
systems that use a central alarm monitoring service. The home central monitoring
panel sends a message to the monitoring station when the alarm is activated.
If the telephone line is in use when an alarm message starts or a phone
instrument is left off the hook, there needs to be a way to clear the line and
override all other call activity. Otherwise, the alarm message could be seriously
delayed or blocked completely. Most security systems are wired to the phone
line using an RJ-31x phone jack. This 8-pin telephone jack is specially designed
to seize the phone line and send the alarm message. As indicated in Figure 3.11,
the RJ-31x jack must be installed between telecommunications equipment in
the home and the demarcation point where the phone line enters the home.
Network
Service
Provider’s
Facilities
Telephone
Line
Network
Demarcation
Point
Customer Premises Equipment and Wiring
Telephone
RJ-31x
Jack
Figure 3.11 RJ-31x jack location.
Unused
RJ-11 Jack
Alarm Dialing
Equipment
Answering
System
Fax Machine
Telephone
Computer
Telephone
Unused
RJ-11 Jack