Alarm Sensors…Are Essential and Primary Elements of Your Home Security System.

Alarm Sensors

A wide variety of security alarm sensors and detectors are available for use in your home security system.Alarm sensors UK are essential and primary elements of your security system, as it operates exclusively on the inputs from them. It is obvious what most sensors do, so I will only describe the main ones used in a basic system.

Contact Sensors About 90% of all burglaries involve external doors, either on entry to your home or leaving it. So undoubtedly the single most important part of your security system planning is the protection of all doors.

Magnetic circuit breakers are an ideal way to protect doors- a magnet is placed on the edge of the door and then with the door closed, a contact is fitted adjacent to it on the doorjamb.

When the door is opened the contact is broken and your alarm control panel recognizes the change and activates the alarm. The door may be closed but not locked, so you still have to lock the doors. It will not detect any breaking of the glass in a glass door.

Your main entry door nearest the keypad, will be programmed with a time lag, to permit you to exit when leaving, and enter on arriving home, without activating the alarm.

Door contacts may be hardwired if mains wiring is available or wireless if not; hardwired contacts are usually recessed in the doorframe, which is less obvious than wireless and are preferable.

Window Contacts Can be hardwired or wireless, are similar to door contacts and designed to sense whether the window is open or closed. Again the contacts will not detect the breaking of glass.

Motion Sensors are another essential device to incorporate into your home security system and are probably the most common form of protection.

There are two main types of motion detectors:-

• Alarm PIR Sensors (Passive Infrared), detects motion by sensing the body heat of a person moving across its field of view. A series of lenses on the cover guide the PIR’s view, which is fixed in one direction.This technology has been fine tuned so that false alarms are minimal these days.

• Dual-Tech motion detectors use two different technologies in the same unit, usually passive infrared plus microwave. These devices are designed to avoid false alarms since both technologies must detect motion before setting off the alarm.

Alarm PIR sensors are reasonably priced and small and can be discreetly mounted on a wall about 7′ from the floor.They should be sited where an intruder is likely to cross. The idea is to guard the most sensitive areas in your home, while at the same time detecting an intruder as early as possible.

E.g. a common hallway, or covering the stairs to the upper floor is a good plan.Pet proof motion detectors are now available to prevent false alarms.

Photoelectric Sensors These project a beam of light across a hall or doorway to detect motion and are triggered when a person passing through interrupts the beam.

Glass Break Detectors Are mounted near windows to detect the specific high frequency sound of glass being shattered. They will not detect if a window or door is opened. They are usually installed on a wall opposite or adjacent to the protected glass and are effective within about 15′ to 25′.

They can be hardwired or wireless and each detector can protect several panes of glass, as long as they are within the specified distance and in a direct line of sight, so one per room normally works well.

Smoke and Heat Detectors These are described in my article under Fire safety at:-

Smoke Alarms UK…Simply Alert You to the Danger of Fire. 

Sensors can also be used to provide many home automation facilities as well as operating your security system, for example a contact breaker on your gate, or a PIR by the door will inform you of the arrival of visitors.

The Bosch Blue Line Detectors…Provide Optimum Performance And Maximum Flexibility

The Optex Sequad PIR Detectors…Uniquely Confirm Activations With Two Independent PIRs.