Tags:Infrared detectors  Smoke alarms  Carbon monoxide alarms

Dual Technology PIR- Dual means two technologies are used in one device. Both technologies must be violated to cause an alarm. These devices are used in harsh environments such as a garage or sun- room. The first technology is passive infrared and works as explained above. The second technology is most often Doppler and looks for the invisible movement of air. If you walk into a room the air has to move as your body mass pushes it along. The reason you would want a dual technology device is clear when you apply common sense to the desired area of protection. For example let’s say you pull your car in to a cool garage, go in the house and turn the alarm on for the night. Your motion detector that you put in your garage will see a dramatic temperature change as the heat from your engine radiates into the cool air. If you had a duel technology motion detector it would not see the air moving because your car is still, so it will refuse to go into an alarm condition.

Pet Immune Motion detector- This is a wonderful advancement in motion detection that may work for you if your pet free- roams your house while you are away and have your motion detectors on. Before the introduction of this technology the pet owner had to either confine their pets from the protected area or bypass the motion detector rendering it useless unless the pet was out of the home with them. The technology is the same as the regular passive infrared detectors. On the pet immune version there are two sets of beams that are offset from each other. Your pet must hit two pre- assigned beams simultaneously in order to violate the detector. Pets under a certain amount of weight (up to 85 pounds) are not long enough to hit both beams so it does not see them. A human torso is designed much differently as per a weight to length ratio causing them to violate either a horizontal or vertical pair of beams, depending on their favorite burglarizing posture.

On the pet immune detectors the middle and lower span of beams are pet immune but the top layer is not, due to the distance of separation between the farthest-reaching beams. Care must be taken on the placement of these devices restricting the high beams from stairways and high ledges your cat may get up on. (6-7 feet high) A good technician will mask only the beams that hit these trouble spots expanding your coverage options.

Remember that even though your device is technically restricted for use by weight of your pet, two or more small animals will have an opportunity to hit the two proper beams while playing with each other. I do not recommend that you use these devices with two or more pets no matter how small they are, unless one of them is rarely moving about. Also one free flying bird will look like a dinosaur entered the room if it flies close to the detector. (They have yet to design the “Dinosaur Immune Detector”)

If your pets do not fall into the allowances for using a pet immune motion detector then you should consider other options for creating interior traps. The well- designed system protects your perimeter as well as possible and creates interior traps in case the perimeter is circumvented.The news come from http://www.bossgoo.com/