Hi,(adsbygoogle = window.adsbygoogle || []).push({});

I did alot of googling and tried to search every forum I could, but I didn't quite found what I was looking for. Sorry if this has been asked before, english isn't my first language so there's a chance that I used wrong words to search for this question.

Also I'm not sure if you use the same type of symbols that we use in Finland for electrical engineering. I will try to explain them if I can =)

Okay to the problem in hand. I am an electrical engineering student, I have studied for 2 years. We had many instances that we had to calculate power factors (symbol that I used is "cos(phi)" and apparent powers (symbol that I used is "S") that the main transformer "sees" in the secondary side.

Here is a picture that I hope clarifies the problem:

http://postimg.org/image/jozu0g543/

Then the question, I have always calculated all the different active- ("P") and reactive ("Q") powers and taken the square of their sums power to get the apparent power ("S"). Equation S = sqrt((sum P)^2 + (sum Q)^2).

And from that I have calculated the power factor. Is there a faster/smarter way of doing this? The way I have been using isn't a problem if you are using under 10 outputs but after that it is quite laborious!

Thanks for your input, and sorry for the long "question", also for my English!

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Different way of calculating power factor from multiple sources

**Physics Forums | Science Articles, Homework Help, Discussion**