In a 120/208-volt 3-phase, 4-wire system, the nominal voltage between any two hot conductors is

In a 120/208-volt 3-phase, 4-wire system, the nominal voltage between any two hot conductors is

• A. 0
• B. 120
• C. 208
• D. 240

Answer: (C)

In a 120/208 V 3-phase 4-wire system, the lines are typically arranged in a wye configuration. In a wye system, each hot line to neutral is 120 V, while the voltage between any two hot lines (line-to-line) is higher. That line-to-line voltage equals the line-to-neutral voltage multiplied by the square root of three. So 120 V × sqrt(3) ≈ 208 V. That’s why the nominal voltage between any two hot conductors is about 208 V. The other numbers don’t fit this system: 0 V would mean the same conductor, and 240 V would correspond to a different system (like a 120/240 V delta or a different configuration).

In a 120/208 V 3-phase 4-wire system, the lines are typically arranged in a wye configuration. In a wye system, each hot line to neutral is 120 V, while the voltage between any two hot lines (line-to-line) is higher. That line-to-line voltage equals the line-to-neutral voltage multiplied by the square root of three. So 120 V × sqrt(3) ≈ 208 V. That’s why the nominal voltage between any two hot conductors is about 208 V. The other numbers don’t fit this system: 0 V would mean the same conductor, and 240 V would correspond to a different system (like a 120/240 V delta or a different configuration).