What is the purpose of a watt-hour meter?

A watt-hour meter serves the specific function of measuring the total electrical energy consumed by a circuit over a period of time. This device records energy use in watt-hours, allowing both utility companies and consumers to monitor energy consumption accurately. Understanding energy usage is crucial for managing costs and efficiency in both residential and commercial settings.

The capability to track energy consumption helps users identify patterns in their usage and make informed decisions about energy conservation. For example, if a household or business notices unusually high consumption on the meter, it can prompt investigation into potential inefficiencies or malfunctioning equipment.

While other devices might measure voltage, check circuit integrity, or manage power supply, those functions fall outside the scope of what a watt-hour meter is designed to do. This specificity in function underscores why the correct answer pertains to measuring electrical energy consumption over time, distinguishing it from other types of electrical testing equipment.