How does a typical voltage regulator operate?

• A. Unregulated voltage enters the line and regulated voltage leaves the load
• B. Regulated voltage enters the line and unregulated leaves the load
• C. Increases voltage to the load without loss
• D. Stores energy to supply peak loads

Answer: (A)

A voltage regulator keeps the voltage at the load constant even as the supply or load current changes. In a typical regulator, unregulated or fluctuating voltage from the source enters the regulator, and through a feedback loop and a control element, the regulator adjusts how much of that input is passed to the load so the output stays at the desired level. The result is a stable voltage delivered to equipment, with any extra input power lost as heat in the regulator. It isn’t designed to push regulated voltage back onto the line, it doesn’t boost voltage without losses, and it isn’t a storage device for peak loads.