The transformers bring a new dimension to the sector of electricity. It is not possible to think the modern electricity without transformers. Many kinds of transformers were invented, such as Power Transformers, Voltage transformers, Measurement Transformers, etc. This blog will describe the equation of the voltage transformer.

## Equation of Voltage Transformer

Power distribution companies are vastly using the voltage transformer. In this transformer, the primary windings turn numbers are more than the secondary windings turn numbers. The type of this transformer is known as a step-down transformer.

It can decrease the voltage from the primary source to the secondary load without the physical connection between the two windings. This kind of transformer does not work depending on the frequency. It will maintain an equation for its works. The equation is, **Np/Ns=Vp/Vs=Is/Ip**.

Here is,

- Np= Primary coils turn number
- Ns= Secondary coils turn number
- Vp= Primary / Input voltage
- Vs= Secondary / Output voltage
- Ip= Primary Current
- Is= Secondary Current

**Example:** If a transformer ratio is 1200:250. The primary voltage is 1000 V, then calculate the secondary voltage.

** Solution: **According to the question,

- Np= 1200
- Ns= 250
- Vp= 1000 V
- Vs= ?

Np/Ns=Vp/Vs

**Vs** =(Ns*Vp)/Np= (250*1000)/1200=** 208 V**

The value of the volt is determined by the ratio of the number of turns of the two windings. Voltage transformers always convert high voltage to low voltage. It is most commonly used in the power distribution sector.