Glass Breakage Detectors

Glass breakage detectors are a type of alarm that react to the sound or vibration of breaking glass. These devices have become a favorite among homeowners because of they consume only a little space and are simple to use.

In the beginning…

The first known glass breakage detector was a metal foil encasing circuits wrapped around the glass, triggering the alarm when the glass breaks. But this did not appeal to the customers because it lacked aesthetics and was difficult to install.

When bugs or piezos came with technology, small glass breakage detectors that were sensitive to vibrations were created. While this allows faster reaction to glass breakage, there was still a problem. This model was sensitive to any vibration, which means that vibrations not caused by glass breakage can trigger a false alarm. Another problem for customers was that each window pane needed separate detectors.

Then came Acoustics, which solved the problem of having a detector for each window pane. Only one Acoustic sensor was needed for a single room, and each can detect sounds within a 35-foot radius. This model detects sounds instead of vibrations and the sensors transmit the sound to a filter which triggers the alarm. However, there was still the problem of being sensitive to other sounds (which sound like breaking glass) and causing a false alarm.

Then there was the dual-technology sensor, which used a microphone and filter that were attuned to two sounds --- the low-frequency sound of a flex wave at the point of breakage, and a high-frequency sound that follows when the glass is breaking.

Installing Glass Breakage Detectors

The glass breakage detectors of today are much simpler to install, unlike those of the old days. The detectors nowadays also require simple mounting procedures. For example, in choosing to mount your model on a window, you have to place it about two inches from the window frame. Mounting procedures might also require you to protect the unit from varying temperature. Improper mounting might also lead to false alarms.

Be wary of the drapes, shutters and blinds. They may interfere with the sensors. Background noise and wave interference might also cause false alarms. Cracked glass will also lead to a malfunction for the detectors.

Other features were also added to glass breakage detectors to obtain an optimal amount of security. Various measures were employed, such as volumetric detectors and magnetic switches.

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