Basic Electrical Installation Work

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Fire Fire chemical reaction which will continue fuel, oxygen and heat are present. Expansion bolts The most well-known expansion bolt made Rawlbolt and consists of a split iron shell held together one end steel ferrule and spring wire clip the other end. Rawlbolts are for heavy-duty masonry fixings. When the alarm initiated, break occurs the wiring, the alarm activated. emergency people not always act rationally, but well-illuminated and easily identified exit routes can help to reduce panic. Extraneous conductive parts The structural steelwork building and other service pipes such gas, water, radiators and sinks. First aid First aid the initial assistance treatment given casualty for any injury sudden illness before the arrival ambulance, doctor other medically qualified person. Ferrous word used describe all metals which the main constituent iron. Flashpoint The lowest temperature which sufficient vapour given off from a flammable substance form explosive gas–air mixture called the flashpoint. Tightening the bolt draws expanding bolt inside the split iron shell, forcing the iron expand and grip the masonry. Exposed conductive parts The metalwork electrical appliance the trunking and conduit an electrical system which can touched because they are not normally live, but which may become live under fault conditions. Fire alarm circuits Fire alarm circuits are wired either normally open normally closed. . First aider first aider someone who has undergone training course administer first aid work and holds current first aid certificate. Fault protection Fault protection provided protective equipotential bonding and auto- matic disconnection the supply (by fuse miniature circuit breaker, MCB) accordance with IEE Regulations 411. Emergency switching Emergency switching involves the rapid disconnection the electrical supply single action remove prevent danger. normally closed circuit, the alarm call points are connected series normally closed contacts. Escape/standby lighting Emergency lighting provided for two reasons; illuminate escape routes, called ‘escape’ lighting; and enable process activity con- tinue after normal lights failure, called ‘standby’ lighting.3 6. Faraday’s law Faraday’s law which states that when conductor cuts cut mag- netic field, emf induced that conductor. In a normally open circuit, the alarm call points are connected parallel with each other that when any alarm point initiated the circuit completed and the sounder gives warning fire.Glossary terms 377 Emergency lighting Emergency lighting not required private homes because the occu- pants are familiar with their surroundings, but public buildings people are unfamiliar surroundings