Basic Electrical Installation Work

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