What does a power factor meter measure?

A power factor meter measures the efficiency of electrical power usage in a system. This efficiency is expressed as the power factor, which is a ratio of the real power (used to do work) to the apparent power (the total power in the circuit). A power factor of 1 indicates that all the energy supplied is being used effectively, while a lower power factor indicates that some energy is wasted, typically as heat or through inefficiencies in the electrical system.

Understanding power factor is vital in electrical systems because it impacts the overall efficiency of energy consumption and can affect utility costs, especially in large industrial setups. It is essential for improving power quality and reducing losses in electrical systems.

The other options, while they relate to different aspects of electrical measurements, do not capture the specific function of a power factor meter. For instance, measuring total energy consumed focuses on watt-hours, while current flowing through a circuit pertains to amperage, and voltage drop across an electrical load involves voltage measurements. These measurements do not provide insights into the efficiency of power usage like a power factor meter does.