Protection Engineering Basics and Schemes Protection Engineering | Page 41

Now if you want to test knee point of Class X CT, you need to step up your voltage up to 6KV. Rest procedure is same.

1.2 Potential Transformer

Potential Transformer is basically a step down transformer, we employee it on line for the purpose of metering and protection.

It always connected in parallel in any circuit, because voltage remains same in parallel paths of any circuit.

1.2.1 Operation:

This instrument transformer totally work like any step down transformer, when high voltage possessed in primary it will induce low voltage in secondary.

Since we knew Ampereturn Primary = Amperturn secondary

V 1

= I 2

= N 1 V 2 I 1 N 2 pg. 41