What is a potential transformer?

Potential transformers are instrument transformers. They have a large number of secondary turns and a fewer number of primary turns. They are used to increase the range of voltmeters in electrical substations and generating stations. SOMETIMES CALLED AS VOLTAGE TRANSFORMERS - USED FOR LINE AND CIRCUIT PROTECTIONS The turns ratio described above is backwards: There is a large number of primary turns and only few secondary turns so that the voltage is stepped down from the high voltagbe used in a power transmission line to a low voltage actually being measured. For example, 13 kV is stepped down to 5 volts which is themn measured using standard instruments. (Walter)

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