Watts to VA Conversion Calculator & Convert W to VA

In this article, we will discuss Watts to VA Conversion Calculator & Convert W to VA. Watt is the unit of real power and VA is the unit of apparent power. Thus, both watt and VA are units of power, however, there exists a subtle difference between them.

In the case of a DC circuit, the real power(watt) and the apparent power(VA) are equal because the power factor of the DC circuit is unity. However, in the case of an AC circuit, the power factor is an important factor in deciding the apparent power(VA) and active or real power(watt) of the AC circuit.

In an AC circuit, the relationship between the real power(watt) and apparent power(VA) can be expressed by the following mathematical expression.

watts to va formula

In simple words, By dividing the watt by the power factor, we get the apparent power.

watts to va conversion formula

Watts to VA Conversion Calculator

The steps for watt to VA conversion are as follows.

  1. Enter Watts
  2. Enter Power Factor
  3. Press calculate Button
  4. The VA value will be displayed in the result field
  5. For the following calculations, press the Reset Button

Examples of Watt to VA conversion

If an induction motor takes 5kW active power at 0.90(lag) power factor from the AC source. Calculate the VA rating of the motor.

Data Given-
P = 5 kW= 5000 Watts
Pf = 0.90

solved problem-1 watt to va calculation

A load connected to a transformer draws 3500 watts at a 0.80 power factor. Calculate the apparent power VA of the load.

solved problem-2 watt to va calculation

W to VA Conversion Table:

The W to VA conversion chart of the standard induction motor rating is given below. The VA rating of 750 Watts motor at 0.90 pf is 833 VA.

W to VA conversion chart of induction motor is shown below.

w to va conversion of induction motor ratings
Point to note: The VA rating of any electrical equipment operating on an AC supply is always more than the watt rating of the equipment. The heater operating on an AC supply has its watts and VA rating equal because of the unity power factor.

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