What is the phase to neutral value of a 13200 volt 3-phase 4-wire system?

In a 3-phase 4-wire system, the phase-to-neutral voltage can be determined using the relationship between line-to-line voltage and phase-to-neutral voltage. The line-to-line voltage (also referred to as the phase-to-phase voltage) in a balanced 3-phase system is related to the phase-to-neutral voltage by the square root of 3.

For a 13200 volt system, the formula to calculate the phase-to-neutral voltage is as follows:

[ \text{Phase-to-neutral voltage} = \frac{\text{Line-to-line voltage}}{\sqrt{3}} ]

Substituting in the values:

[ \text{Phase-to-neutral voltage} = \frac{13200 , \text{volts}}{\sqrt{3}} ]

[ \text{Phase-to-neutral voltage} = \frac{13200}{1.732} \approx 7619.76 , \text{volts} ]

This value rounds to approximately 7620 volts, which corresponds to the correct choice. The calculation is based on the electrical principles governing three-phase systems, where the phase voltages are lower than the line-to-line voltages due to the geometric relationship of the voltages in the system.