Instrument Transformer


Instrument Transformer  

The Instrument transformers are use to step down the AC System voltage and current. The voltage and current level of power system is very high. It is very difficult and costly to design the measuring instruments for measurement of such high level voltage and current. Generally measuring system are designed for 5 A and 110 V.

The measurement of such very large voltage and current, can be made possible by using the Instrument transformers with small rating measuring instruments. Therefore these instrument transformers are very popular in modern power system.

1. Current Transformer 

Current Transformer is used to step down the current of power system to a lower level to make it to be measured by small rating Ammeter.



2. Potential Transformer

Potential transformer used to step down the voltage of power system to a lower level to make it to be measured by small rating voltmeter i.e. 110 – 120 V voltmeter.

Advantages of Instrument Transformers

1.    The large voltage and current of AC Power system can be measured by using small rating measuring instrument i.e. 5 A, 110V.
2.    By using the instrument transformers, measuring instruments can be standardized. Which results in reduction of cost of measuring instrument.
3.    Instrument transformers provide electrical isolation between high voltage power circuit and measuring instruments which also assures the safety of operators.
4.    Several measuring instruments can be connected through a single transformer to power system.

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