Select the number of phases and enter the transformer rating, primary voltage, and secondary voltage. The calculator will evaluate and display the primary and secondary full-load current along with the turn ratio.

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## Transformer Formula

The following formulas are used to calculate the primary and secondary full-load currents.

Single phase full load = tr * 1000 / v

three phase full load = tr * 1000/ (1.73 * V)

- Where tr is the transformer rating
- v is the voltage (either primary or secondary)

The following formula is used to calculate the transformer turns ratio.

Turns Ratio = I2/I1

- Where I1 is the primary current
- I2 is the secondary current

## Transformer Definition

A transformer is a static electrical machine that transfers AC electrical current between two more circuits.

## Transformer Example

How to calculate turns ratio?

**First, determine the value of the primary current.**Measure the primary current.

**Next, determine the value of the secondary current.**Measure the secondary current.

**Finally, calculate the turns ratio.**Calculate the turns ratio using the formula above.

## FAQ

**What is a turns ratio?**

A turns ratio is a ratio of the primary current to the secondary current of a transformer.