Which points are used to measure phase voltage?

Which points are used to measure phase voltage?

• A. Phase A to Neutral.
• B. Phase B to Neutral.
• C. Phase C to Neutral.
• D. Phase C to Phase A.

Answer: (C)

Phase voltage is the voltage of a single phase with respect to the neutral point. To measure it, you connect a voltmeter between that phase conductor and the neutral. In a three-phase system with a neutral, each phase has its own phase voltage to neutral: Phase A to Neutral, Phase B to Neutral, and Phase C to Neutral. This is what the measurement represents when you use Phase C to Neutral. The option showing Phase C to Phase A is a phase-to-phase (line-to-line) voltage, not a phase-to-neutral voltage, so it doesn’t represent phase voltage. In a balanced system, all phase-to-neutral voltages have the same magnitude, while line-to-line voltages are related by the square root of three.

Phase voltage is the voltage of a single phase with respect to the neutral point. To measure it, you connect a voltmeter between that phase conductor and the neutral. In a three-phase system with a neutral, each phase has its own phase voltage to neutral: Phase A to Neutral, Phase B to Neutral, and Phase C to Neutral. This is what the measurement represents when you use Phase C to Neutral. The option showing Phase C to Phase A is a phase-to-phase (line-to-line) voltage, not a phase-to-neutral voltage, so it doesn’t represent phase voltage. In a balanced system, all phase-to-neutral voltages have the same magnitude, while line-to-line voltages are related by the square root of three.