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**mehmood saleem said: **

dear i want knowledge about power factors

our load is 500 ampare

and and current power factors is 0.8

i want pf 0.98

plz tell me this calculation i wated

Dear ;

To ba able to calculate the needed capacitors' power, we shoul know the voltage of the network.

Asune that's ” 400 V “, so, the calculation will be done as the following :

**Q = P ( tg φ1 – tg φ2 )**

where :

– P = 1.73 x 400 x 500 x 0.8 = 276800 W or 276.8 kW

– tg φ1 = 0.75 ( we found it from Cos φ1 = 0.8 )

– tg φ2 = 0.203 ( we found it from Cos φ2 = 0.98 )

So :

**Q** = 276.8 ( 0.75 – 0.203 ) = **151.4** kVAR

That's the power of capacitors that you need, but it's better to install more by 10-15%

Regards.