Basic Electrical Installation Work

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sketch oil immersed transformer can be seen Fig. ● The voltage both the primary and secondary windings propor- tional the number turns. Small trans- formers are used isolating transformers shaver sockets and can also be used supply separated extra low voltage (SELV) sources. Because has moving parts, transformer can have very high efficiency. 5. This includes equipment such water heaters, pumps for showers and whirlpool baths. This often achieved totally immersing the core and windings insulating oil. VP VS IS IP Primary winding turns Secondary winding turns Steel core Magnetic circuit through core FIGURE 5.17 A simple transformer. Large power transformers, used electri- cal distribution systems, can have efficiency better than 90%. FIGURE 5.18. Large power transformers need cooling take the heat generated away from the core. 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. Equipment supplied from SELV source may installed bathroom shower- room, provided that suitably enclosed and protected from the ingress of moisture.Basic Electrical Installation Work 116 ● alternating voltage applied the primary winding establishes an alternating magnetic flux the core. Very small transformers are used electronic applications. This useful for low voltage supplies such domestic bell transformers. ● This means that you increase the number secondary turns you will increase the output voltage.18 Typical oil filled power transformer. ● Alternatively, reducing the number secondary turns will reduce the output voltage. This has application power distribution