Basic Electrical Installation Work

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Intruder alarm systems can broadly divided into three categories those which give perimeter protection, space protection trap protection.52. PIR detectors are often used switch tungsten halogen floodlights because, of all available luminaires, tungsten halogen offers instant high-level illumi- nation. PIR detectors and ultrasonic detectors Definition A movement heat detector placed in room will detect the presence of anyone entering leaving that room. FIGURE 14. This surprise factor often encourages the potential intruder ‘try next door’. Definition An intruder alarm system serves as deterrent potential thief and often reduces home insurance premiums. FIGURE 14.53 A typical PIR detector. Definition PIR detector units allow householder to switch lighting units automati- cally whenever the area covered is approached moving body whose thermal radiation differs from the background. A perimeter protection system places alarm sensors all external doors and windows that intruder can detected she attempts to gain access the protected property. The field view can wide 180°, shown by the diagram Fig. system can comprise one mix- ture all three categories.Basic Electrical Installation Work 336 property.52 PIR detector and field detection. PIR detectors are designed sense heat changes the field view dic- tated the lens system.53. also saves energy because the lamps are only switched when someone approaches the protected area. 14. . Many the ‘better’ detectors use split lens system that number beams have broken before the detector switches the security lighting. intruder alarm system serves deterrent potential thief and often reduces home insurance premiums. the event burglary they alert the occupants, neighbours and officials possible criminal act and generate fear and uncertainty the mind the intruder which encourages more rapid departure. A movement heat detector placed room will detect the presence of anyone entering leaving that room. This capability overcomes the problem of false alarms, and typical PIR shown Fig. This involves fitting proximity switches all external doors and windows. 14. The major contribution secu- rity lighting comes from the ‘unexpected’ high-level illumination area when intruder least expects it. Light fittings must installed out reach intruder order to prevent sabotage the security lighting system. Definition A perimeter protection system places alarm sensors all external doors and windows that intruder can be detected she attempts to gain access the protected property. Intruder alarm systems Alarm systems are now increasingly considered essential feature of home security for all types homes and not just property high-risk areas