Answer :
Final answer:
Yes, buck-boost transformers are suitable for creating a 120/240-volt single-phase service from a 208Y/120-volt 3-phase source. They adjust the voltage to the required level efficiently, and can be used for both increasing and decreasing voltage as needed for travelers' appliances.
Explanation:
Should buck-boost transformers be used to create a 120/240-volt single-phase service fed by a 208Y/120-volt 3-phase, 4-wire source? The use of a buck-boost transformer is indeed appropriate when the available power supply, such as the 208Y/120-volt 3-phase, 4-wire source, does not align with the voltage requirements of equipment designed to operate at 120/240-volt single-phase.
Typically, in commercial and industrial settings where 208Y/120-volt 3-phase power is the standard, certain equipment or areas of the facility may require single-phase power at 120/240 volts. A buck-boost transformer effectively 'bucks' (lowers) or 'boosts' (increases) the voltage to match the requirement. These transformers are very efficient for small changes in voltage and are often used when the difference between the source and the required voltage is less than 20 percent.
For the American traveler in New Zealand, the transformer is used to step down the 240 V to 120 V for appliance compatibility. The ratio of turns in the primary to secondary coils of this transformer would be 2:1 since the voltage is halved. Similarly, the ratio of input to output current would be 1:2, assuming the transformer is ideal with no losses. If a New Zealander were to travel to the United States, she could use the same transformer, but configured in a 'boost' setup to step up the voltage from 120 V to 240 V for her appliances.
