How can you figure out the phase-to-phase voltage?

Prepare for the Southeast Lineman Training Center Exam with quizzes and detailed explanations. Enhance your skills and knowledge through interactive tests. Get exam-ready!

Multiple Choice

How can you figure out the phase-to-phase voltage?

In a balanced three-phase system with a star (wye) connection, the voltage between two lines (phase-to-phase) is √3 times the voltage from a line to neutral (phase-to-ground). This comes from treating the three phase voltages as phasors 120 degrees apart; the difference between two phasors has a magnitude of √3 times the single-phase magnitude. So to find the phase-to-phase voltage from the phase-to-ground voltage, multiply by √3. For example, if the phase-to-ground voltage is V, the phase-to-phase voltage is V√3 (about 1.732V). The other options don’t fit because dividing would give a smaller value, adding three times would be incorrect, and subtracting isn’t the relationship between line and neutral voltages.

In a balanced three-phase system with a star (wye) connection, the voltage between two lines (phase-to-phase) is √3 times the voltage from a line to neutral (phase-to-ground). This comes from treating the three phase voltages as phasors 120 degrees apart; the difference between two phasors has a magnitude of √3 times the single-phase magnitude. So to find the phase-to-phase voltage from the phase-to-ground voltage, multiply by √3. For example, if the phase-to-ground voltage is V, the phase-to-phase voltage is V√3 (about 1.732V). The other options don’t fit because dividing would give a smaller value, adding three times would be incorrect, and subtracting isn’t the relationship between line and neutral voltages.

More practice questions