Alarm systems with motion detectors
PIR (Passive Infrared Motion Detectors) are one type of motion detectors which work with the technology of “passive infrared”, being installed either on a wall or in a corner of a room. These detectors send some invisible fingers all around the room where it is mounted, covering an area of 60 feet straight ahead and 35 feet on the sides.
There are 3 layers of beams that cover the area which is protected.
These PIR detectors use a microchip in order to adjust whenever it’s necessary the device for slow and methodical temperature changes. Using this you won’t be disturbed by the alarm when it is on, because of a difference in temperature in the room.
If you are more attracted by a motion detector that can be mounted on the ceiling, then you will have a covered area of 360 degrees. There are different categories of motion detectors, some can replicate an electric outlet and others are specially made for clients like James Bond. Those who design such products, have made them very small in size and with an aesthetic look which can be mounted in every corner of the room at a height of 5-7 feet.
PIR detectors don’t have the possibility to pass through walls or windows, because they will stop on them and measure the temperature they detect. What is not specifically for these detectors is to bend around corners, because they project forward only. If there is the possibility for a beam to get into another room, then that room will be protected by the motion detector also. If the beam reaches the other room through an open door then it will detect the temperature changes in that room; if the door is closed then the beam will determine the temperature of the door.
It’s basically impossible for a motion detector to protect all the area of your home unless you want to invest a lot of money to buy a large number of detectors. In order to be as much effective as you can, you should place the detectors you have in a strategic way so that they can keep your home safe for the creeps that want to break-in to your house. Most of the times, the perfect trap is made from a detector placed properly on the main floor and the other on the lower level. To keep them isolated at one floor only, you should pay great attention to the stairways.
When an alarm is installed is better to be placed somewhere, where it can best serve the user. Because people want to make their job as easier as they can, they usually place the device in an area where they can easily reach the wires, and forgo the concept of best serving the user. For your best interest is better to insist on speaking with your installer about every motion detector’s place
About Dual Technology PIR
This technology implies a two in one device. If you use such a system, then both technologies must be breached in order to trigger the alarm. Most of the times, these devices are used in places like garages or sun-rooms. The first technology is based on the principle which was explained above and the other one is based on a Doppler system that looks for invisible movement of air. If you want to fully protect a desired area, then a dual technology is the best option. You can think of a scenario where you come home and put your car in the garage and then turn on the alarm. The first second that the detector activates, it will see a dramatic change in the temperature because of the heat from your engine. In the case of an infrared sensor the alarm would trigger, but because you use a dual technology, the motion detector for the air movement will cancel the alarm condition.
About Pet Immune Motion detector
This kind of detector is very useful if you have pets in your house and they stay home alone while you are at work and the alarm is on. Before the technology reached this level, the owner of the pets had options like taking them with him or confine them from the protected area. It’s nothing different from a regular passive infrared detectors. In the case of a pet immune motion detector, you can find two sets of beams that will offset from each other. In order for the alarm to trigger, your pet has to hit two pre-assigned beams in the same time for something to happen. If you have pets under 85 pounds then they are too small to hit these two beams in the same time.
In the case of the pet immune detectors, just the middle and the lower span of beams are pet immune because given the distance of separation between the farthest-reaching beams, there’s no problem for the top layer to be regular. When installing this device, it’s good to look out for places like stairways and high ledges, which can be used by your pets to get to the top layer and trigger the alarm for nothing. For a good technician this can’t be a problem because he can mask these trouble spots and make the coverage options bigger.
Even though this device is restricted for pets that don’t have the right weight, some small pets that play together can overcome this restriction. It is highly recommended not to use these devices if you have in your house more than one pet, unless one of them is rarely moving. A bird can make a lot of troubles if it flies close to the detector.
The last option for you in the case that your pets don’t fall into the allowances for a pet immune motion detector, is to find some other ways of interior traps. The system is very well designed and secures your perimeter very good and makes the traps impossible to avoid in the case of a circumvented perimeter.