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Difference Between Current Transformer and potential transformer

Difference Between Current Transformer and potential transformer

Difference Between Current Transformer and potential transformer



Today we Are discuss the Difference Between Current Transformer and potential transformer. The current transformer measures current and potential transformer Measure voltage. A current transformer is similar in construction to a power transformer that it has a magnetic circuit with a primary and a secondary winding, There is a considerable difference in the method of operation. 

  • In a potential transformer, the primary winding is continuously energized at a substantially constant voltage, and the secondary is connected to a load varying in impedance within wide limits. The current in the primary winding is determined by the load connected to the secondary. The magnetic flux in the core is substantially constant at all loads.

  • The current transformer is connected in the line in series with the load. The load determines the current through the primary. The secondary is connected to a load or burden which does not vary, and the primary current is not affected by the load in the secondary. The current in the secondary is determined by the current in the primary. The magnetic flux in the core varies, with the current in the primary. The flux is determined by the connected burden. The flux density in the core is only a very small fraction of that usually used in a power transformer.

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