What is a "buck and boost" transformer specifically used for?

A "buck and boost" transformer is specifically designed to adjust voltage levels in electrical systems. Its main function is to either lower (buck) or raise (boost) the supply voltage to meet the requirements of specific equipment. In the context of the question, the "buck and boost" transformer effectively changes voltage from 240 volts to 208 volts, which is a common requirement in commercial settings where certain appliances or equipment must operate at a different voltage level than what is supplied.

This use of the transformer helps ensure that equipment operates efficiently and safely, matching its voltage requirement with the available supply. Voltage adjustment is crucial in commercial food service environments, where equipment performance can impact overall operations and service quality.

Other options, while relevant in different contexts, do not pertain to the primary function of a "buck and boost" transformer. For example, converting AC to DC is the role of a rectifier, while isolating circuits typically relies on transformers that provide electrical separation without necessarily altering voltage levels. Stepping up voltage for transmission is a function associated with transformers designed for high voltage applications, which are distinct from the specific voltage adjustment purposes of buck and boost transformers.