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A simple voltage dropper can be used to reduce the voltage for low-power devices; if more than 12V is required, or for high-powered devices, a switched-mode power supply is used. The output will usually be DC in the range 1.5–24 V. Power supplies that output either 100–120 V AC or 210–240 V AC are available; they are called inverters ...
In North America and northern South America, it is usually 120 volts, 60 hertz (Hz), but in Europe, Asia, Africa, and many other parts of the world, it is usually 230 volts, 50 Hz. [2] Aircraft often use 400 Hz power internally, so 50 Hz or 60 Hz to 400 Hz frequency conversion is needed for use in the ground power unit used to power the ...
A capacitor voltage transformer (CVT), is a transformer used in power systems to step down extra high voltage signals and provide a low voltage signal to the actual VT (voltage transformer) used for operating metering/protective relays due to a lower cost than an electromagnetic PT. The circuit diagram for a simple capacitor voltage transformer
In Europe, three-phase 230/400 V is most commonly used. However, 130/225 V, three-wire, two-phase electric power discontinued systems called B1 are used to run old installations in small groups of houses when only two of the three-phase high-voltage conductors are used. The phase shift in Europe is 120°, as is the case with three-phase current.
The primary winding of the transformer is connected to the high voltage or high current circuit, and the meter or relay is connected to the secondary circuit. Instrument transformers may also be used as an isolation transformer so that secondary quantities may be used without affecting the primary circuitry. [14]
They are often used for the power supply of facilities outside settlements, such as isolated houses, farmyards, or pumping stations at voltages below 30 kV. Another application is the power supply of the overhead wire of railways electrified with AC. In this case, single-phase distribution transformers are used. [5]
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An example of an application of an autotransformer is one style of traveler's voltage converter, that allows 230-volt devices to be used on 120-volt supply circuits, or the reverse. An autotransformer with multiple taps may be applied to adjust the voltage at the end of a long distribution circuit to correct for excess voltage drop; when ...