Power formula and current

Thread Starter

Irmutis

Joined May 24, 2009
17
Hi,

This power formula for AC P=U*I*cosfi I=P/U*cosfi
(cosfi is power factor) P=8000W , U=220V, f=50Hz

I have a problem, I do not know how to find current and cosfi? Is it posible what cosfi<=1? If it is , is it posible for example, if I use at home an iron (2000W) that it takes about 10A?
 

Externet

Joined Nov 29, 2005
2,200
Yes.
I=P/U*cosfi
I=2000/220*cos fi

For the soldering iron, being a resistive load, cos fi is 1, then

I=9.09 Amperes

For inductive loads, cos fi can be <1
 
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