Theory & SafetyQuestion 112 of 120
On a 208Y/120-volt wye system, what is the relationship between line voltage and phase voltage?
a.Line voltage equals phase voltage divided by 1.732
b.Line voltage equals phase voltage
c.Line voltage equals phase voltage multiplied by 3
d.Line voltage equals phase voltage multiplied by 1.732
Explanation
In a wye configuration the line voltage is the square root of three times the phase voltage: 120 x 1.732 = 208 volts, while line current equals phase current. In a delta configuration the relationship reverses, with line voltage equal to phase voltage and line current equal to 1.732 times phase current.
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