Background on Glass Break Detection
Glass break detection can be accomplished in a variety of ways. The oldest method is to bond metal foil strips to windows. These strips, when
broken, open a circuit which is detected by an alarm console. These were difficult to install, and somewhat unsightly. More recent technologies
detect the vibration or sound made by breaking glass. A very popular means of glass break detection is to attach a device called a "bug" to the glass being protected. This device directly senses the vibration caused by the impact required to break a glass pane. Two disadvantages exist with the "bug". False alarms are common as a result of vibrations from loud noises, like sonic booms, earthquakes, and similar disturbances. Where multiple panes of glass needed to be protected, a bug had to be attached to each pane.
More recently the technology has moved to detecting the acoustic sounds of breaking glass. This provides the advantage of one detector being able to cover a number of panes of glass. The simpler designs of acoustic detectors sense the high frequency tinkle of shattered glass. These simple designs tend to cause false alarms by confusing the breaking of glass such as tableware, or the sound of bells, with the sound of breaking windows.
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Recently the glass break technology has been improved to eliminate false alarms from common occurrences. IntelliSense has developed a dual technology acoustic glass break detector. The IntelliSense unit listens for the very low frequency sound pressure wave created by the flexing of glass from a blow just before it breaks. This is called the flex wave. Once it detects a flex wave, it enables a high frequency detector to listen for the tinkle of glass breaking. Since both technologies need to detect the glass breaking, false alarms are virtually eliminated.
The IntelliSense FGW-725 Dual Technology Glass Break Detector can be connected to an X-10 alarm system through a door window sensor. This is a battery powered detector designed to work with alarm transmitters. The design of the case provides a cavity to install the circuit board of the X-10 Door/Window sensor. A single 9 volt battery powers both the glass break detector and the door/window sensor circuitry. Having both sets of electronics powered by the same battery assures that the low battery supervision provided by the X-10 alarm system extends coverage to the operation of the IntelliSense Glass Break Detector.
To use the IntelliSense FGW-725 Dual Technology Glass Break Detector with your X-10 alarm system, you just install the circuit board of the X10 DW534 Door/Window Sensor in the IntelliSense unit. To accomplish this, do the following:
