Electric Power Measurement

Overview

Engineering reference data for Electric Power Measurement in electrical engineering.

Key Formulas

Ohm's Law

$V = IR$

Voltage = Current × Resistance.

Power

$P = VI = I^2R = V^2/R$

Electrical power.

Energy

$E = Pt$

Energy = Power × Time.

Variables

Power Measurement Methods

Electric power in a DC or single-phase AC circuit can be determined by measuring the voltage and current. Two common instruments are used:

• Voltmeter (V): Measures the potential difference (voltage) across a component.
• Ammeter (A): Measures the current flowing through the circuit.

By measuring voltage (U) and current (I), power can be calculated using the relationship P = U × I.

Practical Calculation Example

Consider a household circuit with an electric heater:

• Circuit Voltage (U): 230 V
• Measured Current (I): 8 A

Using the formula P = U × I: P = 230 V × 8 A = 1840 W

This means the heater consumes 1840 watts of electric power.

References

• Original Source