How do you calculate the power factor in an AC circuit?

Here's the formula to calculate the power factor:

Power Factor (PF) = P / S

where:

P is the real power in the circuit, measured in watts (W).

S is the apparent power in the circuit, measured in volt-amperes (VA).

Apparent power (S) can be calculated as:

S = V * I

where:

V is the RMS voltage (root mean square voltage), measured in volts (V).

I is the RMS current (root mean square current), measured in amperes (A).

Note: In AC circuits, both voltage and current are sinusoidal, so we use RMS values to represent their effective values.

To calculate the power factor, follow these steps:

Measure the RMS voltage (V) across the load using a voltmeter.

Measure the RMS current (I) flowing through the load using a current meter (ammeter).

Calculate the apparent power (S) using the formula S = V * I.

Measure or calculate the real power (P) consumed by the load (e.g., using a wattmeter or from known power ratings).

Calculate the power factor (PF) using the formula PF = P / S.

The resulting power factor will be a value between 0 and 1. A power factor closer to 1 indicates that the load is operating more efficiently, while a lower power factor indicates that there is a significant reactive power component in the circuit, which can result in wastage of energy. Power factor correction techniques can be applied to improve the power factor if necessary.