Basic Electrical Installation Work

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. The current which flows through the body determined the resistance the human body and the surface resistance the skin the hands and feet. This leads the consideration exceptional precautions where people with wet skin wet surfaces are involved, and the need for special consid- eration bathroom installations. Direct contact with live parts which involves touching terminal line conductor that actually live.1).2. Other methods basic protection include the provision barriers or enclosures which can only opened the use tool, when the sup- ply first disconnected. The insulating material must, course, suitable for the circumstances which they will used and the stresses which they will subjected. Try This Definitions ● help you remember these definitions try writing them out your own words ● just identify the essential words. The IEE Regulations call this basic protection (IEE Regulation 131.7 this book. The Regulations call this basic protection. 6. All live parts are enclosed in insulating material such rubber plastic, which prevents contact with those parts. Protection can also provided fixed obstacles such guardrail around open switchboard placing live parts out of reach with overhead lines. The Regulations call this fault protection. In installations operating normal mains voltage, the primary method of protection against direct contact insulation.Overcurrent, short circuit and earth fault protection 235 Protective equipotential bonding this equipotential bonding for the purpose safety shown Fig. Basic protection and fault protection The human body’s movements are controlled the nervous system. Indirect contact results from contact with exposed conductive part such as the metal structure piece equipment that has become live a result fault. Definition Protective equipotential bonding this is equipotential bonding for the pur- pose safety shown Fig. Two types contact will result person receiving electric shock. If the body becomes part more powerful external circuit, such the electrical mains, and current flows through it, the body’s normal electrical operations are disrupted. 6. Very tiny electrical signals travel between the central nervous system and the muscles, stimulating operation the muscles, which enable walk, talk and run and remember that the heart also muscle. The shock current causes unnatural operation of the muscles and the result may that the person unable release the live conductor causing the shock, the person may thrown across the room.7 of this book