Question

The line currents are ________ behind respective phase currents in a delta connected system.

(a) 120⁰

(b) 90⁰

(c) 60⁰

(d) 30⁰

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This interesting question is from Voltage, Current and Power in a Delta Connected System in section Polyphase Circuits of Network Theory

Answer 1

Correct answer is (d) 30⁰

The explanation is: In a delta connected system, all the line currents are equal in magnitude but displaced by 120⁰ from one another and the line currents are 30⁰ behind the respective phase currents.