Answer: B - Constant voltage transformers regulate brownouts. Brownouts are caused by a reduction in voltage. This happens when power companies are experiencing high demand and reduce the voltage in an electrical grid. Constant voltage transformers are used to regulate this fluctuation of power. They can use different ranges of voltage and only release the expected 120 volts of alternating current to devices.
A constant voltage transformer is also referred to as a ferro-resonant transformer. It regulates its output voltage without switching to an alternate power source, such as batteries. “internally” hardened equipment that can protect loads from the wide variety of power quality variations that may cause building, grid, or systemwide problems.
