PERFORMANCE LIMITS
DE5467U
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10. PERFORMANCE LIMITS
Although the alarm control system you purchased is
highly reliable, it does not guarantee protection from
burglary and fire hazards. Even the most advanced
systems can be defeated or might occasionally fail to
warn. Some of the reasons for this are:
Sloppy maintenance:
If the system is used over a
long period of time without testing, a key element
such as a detector or a siren might go wrong without
any visible or audible signs of failure. If a low battery
warning is neglected, there will be no backup power
to keep the system operational during a power
outage.
Power failures:
In case of prolonged absence from
the protected site, the mains supply may suddenly
fail (an earth leakage protection relay may trip,
disconnecting the mains supply). After such an
event, the alarm system will draw power from the
backup battery, until all reserve power is exhausted,
leaving the premises without protection.
Telephone line trouble:
Telephone lines may be
disconnected or short circuited. With the telephone
line "down", your alarm system will not be able to
report events to the central station.
Sirens do not always wake up sound sleepers:
Sirens and bells installed outside or far from
bedrooms are not likely to awaken people who are
sound asleep behind closed doors inside the
protected area or in adjacent buildings.
The system is sometimes defeated:
With sufficient
technical know-how, intruders may find a way to
defeat various types of sensor or disconnect warning
devices. Intruders may also take advantage of
unprotected openings and skylights, or even enter
forcibly at unpredictable spots.
Smoke detectors have their limits:
In many cases,
smoke detectors fail to warn on time because the fire
started at a different level of the house, or too far
away from the detector.
All this gives sufficient proof that even with a
good alarm system installed, there is still need
for life and property insurance. In addition, users
should test their alarm systems at regular
intervals, to make sure that malfunctions are
detected before a true alarm event occurs.
