Vibration
Detectors
Mounted on the
window frame or glass itself, vibration detectors react to vibrations
that are created if someone attempts to break or shatter the glass.
Also referred to as shock or vibration sensors, they are adjusted to
avoid false alarms by allowing normal vibrations on the glass. Glass
mounted vibration detectors require the use of an attached (visible)
wire and are placed about an inch from a corner frame, where acoustic
waves concentrate on shock to the glass. Though glass mounted vibration
detectors have less probability of false alarm over frame mounted, their
use is restricted to stationary glass where the appearance of the lead
wire is not an aesthetic concern.
Audio
Discriminators
Frequently, several windows or glass openings can be protected by installing
an audio discriminator that will sense glass breaking. Also referred
to as acoustical or sound detectors, these security devices can be mounted
on the frame, wall or ceiling. They are tuned to alarm on specific sound
frequencies that correspond to breaking glass or excessively loud noises.
Sound detectors are susceptible to loud background noises (music, machinery)
and their sensitivity can be reduced by window coverings and other sound
dampening materials. The device's sensitivity is adjustable so that
ambient noises or normal sounds will not trigger an alarm.
Alarmed
Window Screens
Standard window screens can be laced to provide protection in the event
they are cut or removed. This provides the added convenience of allowing
windows to be open and the security system to remain intact when armed.
A special wire woven into the screening material such that if the screen
is cut an alarm is triggered. Existing window screens can be wired and
then re-installed on the windows.
Commercial Security |
Residential
Security
