Basic Electrical Installation Work

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