On average every 20 seconds a property in the UK is broken into. However, Government statistics have shown that around 60% of all burglaries carried out on homes fitted with burglar alarms are unsuccessful. Consideration should also be given to the numerous burglaries that have been prevented in the first place by the obvious presence of a professionally fitted burglar alarm system.

Stewart Intruder Alarms Ltd are N. Irelands oldest local installer of electronic security systems, we are a NACOSS Gold company, which is the highest accreditation for an Intruder Alarm Company. So you, your family or your business will benefit immediately against attacks by intruders safe in the knowledge that you’re protected by a professionally installed intruder alarm system, backed by years of experience and rigorous regular inspections of our company by the National Security Inspectorate.

Magnetic Contacts

Magnetic Contacts are simple but effective magnetic switches useful for detecting the opening (occasionally closing) of windows and doors. When fitted to a typical door the switch is fitted to the door frame and the magnet to the door. The magnetic contact and associated wiring will always be fitted on the protected side of the door. The units are supplied in two parts, the switch - which comprises a magnetic reed switch and the magnet - which operates the reed switch when suitably sited. The reed switch is almost always fitted in the stationary part of the door or window and the magnet in the moving part. Flush contacts are fitted into the edge of the door (magnet) and the door frame (switch).



PIR Sensor (Wall Mounted)

PIR stands for Passive Infra Red, this means it's a passive device, one which does not emit signals, it simply waits passively until an infra red (body heat) signal is focused onto a detecting chip via the front flat lens. This lens divides the room into segments and it is the movement of the infra red signal, (an intruder) from one segment to the other which triggers the device, this in turn triggers a control panel and the alarm system. Different versions are available to cover very large rooms or long corridors. Passive infra-red detectors are widely used due to their ease and neatness of installation, low cost and reliability. They can however be subject to false alarms under certain conditions e.g. where there may be sudden fluctuations in temperature. Quad versions offer increased protection against false alarms.
For further increased protection against false alarms, Dual Technology devices can be used. These devices only alarm when both the PIR part of the detector AND the microwave element detect an alarm situation. The PIR element detects changes in heat and the Microwave element detects changes in space e.g. when a door is opened the amount of space that the microwave 'sees' is altered and an alarm condition is triggered

Quad PIR Sensor (Wall Mounted)

We would normally recommend and install Quad PIR sensors as Quad Zone Logic provides multi segmented detection zones over the detection area. This type of PIR sensor is more stable and false alarm free than a basic PIR. The sensor detects in zones and an alarm signal is created by the cumulated total IR energy of each zone. It is designed so that a human size target will normally fill 4 to 8 zones, and this will cause an alarm to be generated. Any smaller temperature change (i.e. small to medium size pets, rodents or moving curtains) only activates one or two zones at the same time creating a much weaker detection signal. Pet immunity applies to animals 0 to 16 inches in height. These signals are further analyzed by the "ECO" chip and signal processing circuit for accurate detection of humans and avoidance of most small animals. In addition there is an anti masking version which has all the features of the normal Quad Sensor, with the addition of anti masking this sensor detects accidental and intentional masking of the detector.


Quad P.I.R. Sensor (Ceiling Mounted)

This device is mounted on the ceiling and looks down, the example shown is the Optex KX-08 which rejects false alarms caused by spot temperature changes such as small to medium sized animals, air conditioners, or moving curtains. Utilizing Quad Zone Logic, the KX-08 couples signals from its 78 detection zones to determine the size of its target. Its high quality Spherical Lens and its dense detection pattern give the KX-08 Catch and Pet Immunity that is superior to single technology detectors. KX-08 also has an insect shield sealed housing



Dual Technology Sensor.

A combination of both PIR and Microwave technologies, in effect two different types of sensor in the one box, a body heat movement sensor and a movement sensor, similar to radar. It is designed so the both sensors must be activated before a signal is sent to the control panel thus ensuring a very low rate of false alarms, as a situation that may cause a false alarm in a PIR won’t necessarily cause a false alarm in the microwave sensor and visa versa.

Various ranges are available to cover most applications.

Plus there is an anti masking version which has all the features of the normal Dual Technology Sensor, but with the addition of anti masking which detects accidental and intentional masking of the detector.


Photoelectric Beams

Outdoor photoelectric detectors with dual infra red beams for high immunity to false alarms caused by falling leaves, birds, blowing debris, and other outdoor hazards. These are in effect electronic trip wires, two modulated infrared beams of light are sent from the transmitter to the receiver and if they are blocked by a car or person passing through them a signal is sent to suitable control equipment, which in turn triggers sounders, communicators, lights, or whatever combination of warning devices you require. Most units also feature good beam blockage tolerance for fog etc, adjustable beam interruption period for fast moving objects such as birds etc. These units can activate alarms, warn of approaching intruders, switch on lights etc. A very flexable device which can be used to create various types of pre warning systems. For example in its simplest form they can be used to sound a discreet sounder in a house to warn of a person entering the driveway and switch on outside lights at the same time.

This window guarding unit which offers reliable protection and various security options. This is designed to protect the perimeter of the building. Areas like windows and roll-up doors have been secured only by magnetic contacts or glass break detectors so far. Now, these units protect a building's exterior by detecting intruders before entry is attempted and can also provide a deterrent with a sounder before the break-in occurs. These photoelectric units can be very stable and effective in large warehouses where air movement, animals and other types of unavoidable movements could trigger conventional PIR or Dualtechnology Sensors.

Control Panels

The Control Panel is the heart of the system and the make and model are usually chosen to suit the overall requirements of the customer and the protection required. However most control panels have the following main features.

• Mains Power with backup rechargeable battery
• NVM (Non-Volatile Memory - retains user settings when all power is removed, can be reset to factory settings if required)
• Multiple detection zones - usually programmable as
• Entry/exit
• Access
• Immediate
• Fire
• Personal Attack
• Auxiliary Power Supply
• Tamper circuits and tamper protected cases
• External sounder connections
• Internal sounder connections

Blank end stations, which are simply a square blank box usually about a foot square and 5 inches deep, which contains the main power supply, batteries, and electronics, can be sited wherever is convenient and secure, and a remote keypad or more if required, fitted in a suitable location/locations to switch the panel on and off.
This example, the Scantronic 9851 control panel is a fully programmable, 8 or 16 zone alarm panel, which can be expanded to 40 zones. The system can be expanded using hardwired or Class VI 868 MHz narrow band wire free technology ensuring flexibility whatever the installation requirement. It can be switched on and off using the remote keypad, a small keyfob touched to the keypad or remotely at a distance with a radio keyfob.

The 9851 is ideally suited to the small and medium size commercial market. Designed to offer maximum flexibility and ease of use, up to 4 remote keypads can be housed in separate locations of the building.

Exceptionally easy to operate using large backlit A, B, C and D buttons you can have level setting or 4 partition options of the whole premises, ground floor only or any other plan that suits your particular setting requirements.

Upload and download technology is available using a Windows based program, which greatly reduces maintenance time by allowing the engineer to diagnose and program the system remotely.

Additionally, the 9851 has a 250 event log which is locally printable and downloadable. There is a built in 2400/300 baud CCITT V21 full duplex modem for communications and secondary communications.

Monitoring

How does a monitored alarm work?
Your alarm system has a communicator/modem incorporated into the main circuit board, which connects to your phone line and "dials" the alarm receiving centre (central station) and communicates with the central station computers. The alarm control panel sends signals to the central station computers which identify the specific location of the alarm system (or the protected premise), the nature of the alarm (burglary, fire, panic, duress...) and if required the location of the problem (front door, basement motion detector, attic smoke detector...).

What then happens at the central station?
After the information has been received from the alarm system, the central station computer brings up the information along with the appropriate police, fire and medical departments for the central station operator to contact. The operator will be aware of any special instructions that may have been provided and will know how to handle each individual situation that can occur with the alarm system.

A general response from the central station for a burglar alarm signal is to make a phone call to the premise and ask for the alarm password. If there is no answer or if the person answering does not have the proper password, then either the police are notified and/or keyholders are contacted, the order in which this is done depends on the customer’s specific instructions and the police policy currently in force.

Customized responses could include notifying a guard company, or only notifying the emergency call list and not the police. Alarm monitoring with today's burglar and fire alarm controls gives the central station a considerable amount of information concerning the status of the alarm. Customisation of response through the central station operator allows the premise owner the maximum flexibility of response to an alarm activation of any kind.



Redcare

redcare offers the most secure form of alarm monitoring available. The service provides continuous monitoring of a BT telephone line that links a professionally installed alarm system on a customer’s premises to an Alarm Receiving Centre (ARC). The result is continuous protection of our customers' property, every second of the day, 365 days a year.

Unlike other alarm monitoring services, redcare both alerts the Alarm Receiving Centre when it detects a line cut AND provides encryption to prevent the substitution of equipment or "spoofing" (emulation) of line conditions. This is why redcare is the most secure system of its kind.

Key benefits and features

• redcare is a Secured By Design product and as such has gained Police Preferred Specification status. This was achieved after testing against and meeting the highest grade (Grade 4) of European Standard 50131.
• No need for an extra telephone line (a Modem Compatible Device may be required if fax and data services are to be used on same line).
• Active, continuous 2-way monitoring - 24 hours a day, every day of the year.
• High-speed alarm transmission summons help within a matter of seconds.
• Alarm signals can be delivered to the Monitoring Station even when the phone is in use.
• Encrypted signals which cannot be replicated.
• Instant detection if your phone line has been cut.
• No additional call charges.

Redcare GSM

redcare gsm combines a secure redcare landline connection with a GSM radio backup path. In the event of a line cut it enables alarm signals to continue to be monitored by the radio path.
If the BT landline fails, the Monitoring Station will receive a communication failure message. The GSM path will continue to communicate with the alarm receiving centre, sending any subsequent alarms.
redcare gsm is capable of sending a confirmed activation if either the primary landline or secondary radio path is lost, regardless of which one is lost first.

Sounders
All our systems would normally have two sounders fitted, one external and one internal. When the alarm system triggers both sounders operate. This is normally enough to deter the intruder from going any further and gives an audible warning to anyone nearby that something is amiss. In addition to the sound output the external sounder also has a flashing strobe light for visual identification of the premises where the alarm is triggered.