Basic Electrical Installation Work

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nearby motorway junction can, however, greatly increase the risk factor. Intruder alarms The installation security alarm systems the United Kingdom already a multi-million-pound business and yet also relatively new industry. Taking the simplest precautions will reduce the risk, while installing security system can greatly reduce the risk successful burglary. ‘Bad men all hate the light and avoid it, for fear their practices should be shown up’ (John 3:20). Not all homes are equally risk, but all homes have something value to a thief. Most intruders are looking for portable and easily saleable items such as video recorders, television sets, home computers, jewellery, cameras, silverware, money, cheque books credit cards. Passive infra-red detectors Passive infra-red (PIR) detector units allow householder switch on lighting units automatically whenever the area covered approached by a moving body whose thermal radiation differs from the background. The Home Office has stated that only homes are sufficiently protected against intruders, although 75% householders believe they are secure. Police forces agree that homes and public buildings which are externally well illuminated are much less attractive target for the thief. They ide- ally want get and away quickly but, they can work unseen, they may take lot trouble gain access property by, for example, removing the glass from window. Security lighting installed the outside the home may activated by external detectors.51). recent study carried out Middlesex University has shown that two London boroughs the crime figures were reduced by improving the lighting levels. As society becomes increasingly aware crime prevention, evident that the market for security systems will expand. This will deter most potential intruders while also acting courtesy lighting for vis- itors (Fig. Flats and maison- ettes are the most vulnerable, with other types property roughly equal risk. Properties cities are highest risk, followed homes towns and villages, and least risk are homes rural areas. These detectors sense the presence person outside the protected property and additional lighting switched on.1 and 560.7.51 Security lighting reduces crime. 14. . Most intruders are young, and foolhardy opportunists. Definition Security lighting the first line of defence the fight against crime.1). Security lighting Security lighting the first line defence the fight against crime. This type detector ideal for driveways dark areas around the protected FIGURE 14.Electrical installations and wiring systems 335 Fire alarm circuits are Band circuits and consequently cables forming part fire alarm installation must physically segregated from all Band II circuits unless they are insulated for the highest voltage (IEE Regulations 528