Author: Mike Norton
We can combine a variety of detectors to your Alarm System such as Motion, Smoke, Glass break, Door Reed and even Seismic (for safes) detectors to mention a few. The following is an overview of each type of detector that you can purchase from us and may help you make an informed purchasing decision.
Motion Sensors (PIR's)
We have field tested most makes of alarm detectors over the years and have found that the Bosch, Paradox and Honeywell detectors provide the best reliability and value for money.
The standard Double Passive Infrared detector is normally installed to our domestic premises without pets, as these sensors provide fast detection of intruders with good reliability in a normal household environment.
When pets are present at the property or we are installing into the commercial premises for those hot and sometimes dusty environments, or rooms with more than 30% windows, we recommend an upgrade to the more robust and pet friendly PIR detectors.
These detectors provide outstanding reliability in normal or harsh environments like warehouses, shops, garages and conservatories where drafts or direct sunlight may cause standard sensors to false alarm. These Triple Technology detectors also incorporate intelligent processing software that ignores one or more pets from a weight of 20-50KG.
iCam Security alarm systems have the ability to utilise wireless alarm detectors if required by the customer. We are able to install wireless standard and dual technology movement detectors, door opening, door and window vibration detectors and even wireless smoke detectors. Wireless detectors can be installed throughout the premises or just to locations where it is difficult to install wired detectors like conservatories, outbuildings or ground floors if a 2+ story building.
In addition, wireless remote control key fobs with inbuilt panic alarm button can be added to the system to allow the system to be turned on and off without going to the control keypad. The panic button requires two buttons to be pressed together to activate the alarm sounders and can be used inside or outside the premises.
Passive Infrared Motion Detectors
These detectors are also known as PIR detectors as the technology they utilise is “passive infrared”. The device is mounted on a wall or in the corner of a room. It sends invisible fingers out into the covered area in several layers. The top layer goes the furthest and averages about 60 feet straight ahead and 35 feet on the sides. The centre layer of beams spreads the area about mid-way and the bottom layer sweeps the room closest to the detector.
These beams individually measure the infrared temperature of whatever they land on and look for a clash of temperature against that point. For example if a beam lands on your couch and knows what temperature it is, when you walk in front of the couch your temperature is different and causes a violation. You would be hard pressed to match the temperature of everything in your home as you walk about and that makes motion detectors hard to compromise.
Pet Immune Motion Detector
This is a wonderful advancement in motion detection that’s lets your pets freely roam about your house while you are away and have your Alarm and motion detectors armed. 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 very different on a per weight to length ratio, causing them to violate either a horizontal or vertical pair of beams, depending on their favourite burglarizing posture.
Microwave Motion Detector (Dual Technology)
The introduction of the microwave sensor has escalated the robustness of the PIR even further. When dealing with the harsh Australian environments some of the older PIR’s can cause false alarms by detecting the movement of heat. For example:
1. Heat rising from a dish washer when it has finished its washing cycle and triggering the PIR.
2. An air conditioner starts up and pushes cold air out which pushes a mass of hot air across the room triggering the PIR.
3. The sun directly heating a glass window, heating the air on the inside, then a draft in the house pushes the air across the room triggering the PIR.
The Microwave PIR is generally used for harsh environments (insects, conservatories etc) and makes use of the Dual Technology which handles any heat changes effectively. Dual Technology (DT) detectors comprise a PIR and a Microwave detector in the same unit and both detectors have to be triggered to create an alarm condition. This detector works in the same way as a standard PIR but the Microwave detector essentially 'sees' space. The microwave unit emits a microwave signal which bounces around the room and is then received back where it is converted into a particular value then, any change to the volume of the room or the movement of objects (intruders) within the room will cause a change in the received signal. If this change in signal is deemed significant then an alarm is triggered. The microwave sensitivity and range are adjustable manually and will require our technician to thoroughly test the system.
Glass-break detectors are also known as “Audio Discriminators”. They are a perimeter device because they catch a burglar attempting to make entry into your home or business as opposed to walking around the interior and being picked up by a motion detector. They are available in both hardwired and wireless versions. These detectors mount on a wall or ceiling and listen to an area approximately 35 feet in all directions. They do not hear through walls or around corners or into a room because the door is open. The more windows you have in a device’s area of protection, the better the value.
The glass break detector listens for the frequency of breaking glass and splintering wood. In the not so distant past the only glass breaks available were “Single Technology” devices. These listened for the frequency of breaking glass and splintering wood only. The problem was that sounds such as lightning cracking, some people’s sneezes, clinking two glasses together in the sink, or a pet bird squawking would replicate this frequency and cause false alarms that only the most cunning thieves could figure out.
Although the single technology devices are still being used today because they cost most alarm companies less to purchase, we insist on the newer “Duel Technology” device. The new devices must hear a “Thump” and then a frequency hit, in that precise order in order to go into an alarm condition.
Alarm Contacts – REED Switches
Contact switches are magnetic switches used to protect doors and windows. There are three main styles that are used. They are recessed contacts, surface mount contacts and roller-ball contacts.
Recessed contacts are hidden in the window tracks and door jams so that they can’t be seen when the window or door is closed. The switch is on the fixed or non-movable side of the opening and a magnet is placed on the movable side. When the magnet meets the switch the circuit is complete and the control knows it is closed. Recessed contacts are more complicated to install unless they are placed during the construction phase of your home or business. We can install recessed contacts in your home after construction as long as we have space to run the cables.
Surface mount contacts function the same as recessed ones however they are visible when the doors or windows are closed. They come in three main sizes being large, small and micro. They come in different colours so they can blend in to the door trim or window sill they are mounted on.
Roller-ball contacts are in the hinge side of your door jam and the spring loaded ball is pushed in when the door is closed completing the circuit. These are more likely to need replacement in a few years as they are considered a moving part.
All types of recessed and surface mount contacts can be hardwired directly to your control panel or you can get them in a wireless version. Wireless contacts have a transmitter tied to them or built into them that sends a radio signal to a receiver in the control. The transmitter is surface mounted.
Alarm System Smoke & Heat Detectors
Smoke detectors are available that will interface directly with your security system. The smoke detectors that are already in your home or business can’t be tied into your security system. The device that the builder put in your home is either electrical, battery operated, or in some instances both, if you have the better quality detectors. If you elect to add some to your system, your existing detectors should be left in place, as they are still able to help give early warning in case of a fire.
There are many advantages to adding fire devices to your security system. Some of them are:
- Your detector is on all the time, even if your alarm is disarmed.
- The devices work off the power from your alarm system and use its backup power supplies should power fail.
- The siren will emit a tone that is audibly different then a burglary siren, so that you can differentiate.
- If monitored, the fire services are dispatched without you having to call for help yourself. This gives you more time to gather your loved ones and pets for immediate evacuation.
- An emergency call will take place even if you are not home. Typically flames will be coming through your roof, by the time your neighbours see them, and call for help. This early response may save your pets and a good portion of your home.
- Insurance companies often give an additional discount, off your homeowners insurance, for having a fire system. These devices could effectively pay for themselves, after a few years.