3 phase Delta / Star : Line or Phase?

AI Thread Summary
In three-phase systems, "line" refers to the voltage or current measured between any two lines, while "phase" refers to the voltage or current in a single phase. For star (Y) configurations, the phase current is equal to the line current, meaning they are the same. In contrast, for delta (Δ) configurations, the phase current is one-third of the line current, specifically calculated as phase current equals line current divided by √3. When calculating current using voltage divided by impedance, the result will be phase current in both configurations, but the relationship to line current differs. Understanding these distinctions is crucial for accurately determining line versus phase values in electrical engineering.
Cocoleia
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Homework Statement


I am studying for an exam and I never know if I am finding line current / voltage or phase current / voltage. How can I tell? I guess I am confused on what "phase" and "line" represent. For example:
upload_2017-10-29_17-7-2.png

If I do the voltage divided by the impedance, then this gives me phase current, but how do I know?

Does it differ for star and delta configurations? If this example would have been in star would I still have found the phase current by doing that division ?
 

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Cocoleia said:
If I do the voltage divided by the impedance, then this gives me phase current,
And for star, it is equal to line current. For delta, phase current is equal to 1/√3 times the line current.
 

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