Basic Electrical Installation Work

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They are good insulators, but give off toxic fumes when burned. Most corrosion takes place when metal contact with moisture (see also mild steel and zinc). It good insulator, but degrades and becomes brittle when exposed to sunlight. They are non-magnetic and resist rusting. Definition Alloy alloy mixture two or more metals. Synthetic artificial rubber carefully manufactured have all the . An insulator material, usually non-metal, which the electrons are very firmly bound the nucleus and, therefore, will not allow heat elec- tricity pass through it. They have a flexible quality when operated maximum temperature 70°C but should not flexed when the air temperature near 0°C, otherwise they may crack. Definition Non-ferrous Metals which not con- tain iron are called non-ferrous. The word ‘ferrous’ comes from the Latin word ferrum meaning iron. These electrons can easily become ‘free electrons’ which allows heat and electricity pass easily through the material. 4. All materials are made atoms and electrons. Brass alloy cop- per and zinc, usually the ratio 70–30% 60–40%. Plug tops, socket outlets and switch plates are made from this material. Copper, aluminium, tin, lead, zinc and brass are examples non-ferrous metals. Cast iron, wrought iron and steel are all ferrous metals. These electrons can easily become ‘free electrons’ which allows heat and electricity pass easily through the material. Definition Polyvinylchloride (PVC) used for cable insulation thermoplastic polymer. Ferrous metals have magnetic properties. Polyvinylchloride (PVC) used for cable insulation thermo- plastic polymer. Non-ferrous Metals which not contain iron are called non-ferrous. Definition An insulator material, usually a non metal, which the electrons are very firmly bound the nucleus and, therefore, will not allow heat elec- tricity pass through it. Synthetic rubber manufactured, opposed being produced natu- rally. Let now define the terms and properties some the materials used in the electrotechnical industry. Definition Ferrous word used describe all metals which the main constituent is iron.1 the last chapter looked the atomic structure materials. Definition Thermoplastic polymers These may be repeatedly warmed and cooled with- out appreciable changes occurring in the properties the material. Definition Corrosion The destruction metal by chemical action. Corrosion The destruction metal chemical action. What makes them differ- ent materials the way which the atoms and electrons are arranged and how strongly the electrons are attracted the atoms. A conductor material, usually metal, which the electrons are loosely bound the central nucleus. Thermosetting polymers Once heated and formed, products made from thermosetting polymers are fixed rigidly. Ferrous word used describe all metals which the main constituent is iron. Definition A conductor material, usually a metal, which the electrons are loosely bound the central nucleus. Alloy alloy mixture two more metals. Thermoplastic polymers These may repeatedly warmed and cooled without appreciable changes occurring the properties the material. Rubber tough elastic substance made from the sap tropical plants.Basic Electrical Installation Work 100 Properties conductors and insulators In Fig