Basic Electrical Installation Work

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5.18. This has application power distribution. ● The voltage both the primary and secondary windings propor- tional the number turns. VP VS IS IP Primary winding turns Secondary winding turns Steel core Magnetic circuit through core FIGURE 5. This includes equipment such water heaters, pumps for showers and whirlpool baths.Basic Electrical Installation Work 116 ● alternating voltage applied the primary winding establishes an alternating magnetic flux the core. This useful for low voltage supplies such domestic bell transformers. FIGURE 5. Very small transformers are used electronic applications. Because has moving parts, transformer can have very high efficiency.17 A simple transformer. This often achieved totally immersing the core and windings insulating oil. sketch oil immersed transformer can be seen Fig. Try This Have you seen any transformers action? Were they big small what were they being used for? Have you been close transmission tower, perhaps when you were walking in the countryside? . ● The magnetic flux the core causes voltage induced the secondary winding the transformers. Small trans- formers are used isolating transformers shaver sockets and can also be used supply separated extra low voltage (SELV) sources. Large power transformers, used electri- cal distribution systems, can have efficiency better than 90%. ● This means that you increase the number secondary turns you will increase the output voltage. ● Alternatively, reducing the number secondary turns will reduce the output voltage.18 Typical oil filled power transformer. Large power transformers need cooling take the heat generated away from the core. Equipment supplied from SELV source may installed bathroom shower- room, provided that suitably enclosed and protected from the ingress of moisture