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