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1. ### THD valve and PF valve for LED light. Should I care about it?

PF is Power factor and THD is Total harmonic ...electricity is metered to your business. If they charge for PF , it might have a very small additional cost. But if you have a PF meter...

1 Answers · Science & Mathematics · 21/07/2013

2. ### How do I calculate the high time and low time of a 555 timer circuit? R1= 1K Ohms R2= 68k Ohms C= 2.2 pF ?

2 pF is much too low a value for this application. The timing cap should be at least 1000 pf for any accuracy. It can be as low as 200 pF . in the one-shot mode...

2 Answers · Science & Mathematics · 14/11/2009

3. ### Would like actual formulas for PF capacitor sizing?

..., or kW = 746 x HP/1000 2. Nameplate gives PF , usually around 0.8. . . So 0.8 is CosØ1, so calculate...

2 Answers · Science & Mathematics · 15/11/2009

4. ### how do you solve for power factor when KW and PF are unknown?

PF = Kw/ sqrt (Kw^2 + Kvar^2) Kva = sqrt (Kw^2 + Kvar^2) Pf = cos angle between voltage and current In order to calculate PF you must know...

1 Answers · Science & Mathematics · 19/07/2012

5. ### Is 6800 pF = 6.8 X 10^-3 uF?

yes 6800 pF = 6800 e–12 farads = 6.8 e–9 farads since µF..., and would never be used in practice. It would be 6800 pF or 6.8 nF .

3 Answers · Science & Mathematics · 15/09/2009

6. ### A parallel-plate air-filled capacitor has a capacitance of 43 pF .?

43 pF = 0.000043 microF using the equation C=(k*epilison*Area)/separation where, epsilon = 8.854*10^-12 F/m C= 43 pF A=0.28 k=1.0 solve for d (separation) d=5.765 cm b) C = (8.2...

3 Answers · Science & Mathematics · 02/03/2011

7. ### What does .0015mfd equal in pF 's?

...actually a 0.0015 µF cap. That is 1.5 nF or 1500 pF The 0.005 mF is probably actually a 0.005 µF cap...

3 Answers · Science & Mathematics · 03/01/2011

8. ### Which one of these formulas is the correct one for finding power factor ( pf )?

pf =cos(theta) where theta is the phase angle between the voltage and current. There is no reason to use the dot product or cross product.

2 Answers · Science & Mathematics · 20/11/2013

9. ### why 3 phase motor no load pf is high?

Yes. pf should be less at no load. Compare the current drawn by the motor at...

5 Answers · Science & Mathematics · 01/07/2013

10. ### why we need to know VARS and pf of transformer?

... of the transformer's equivalent circuit component values. The pf determined in the open circuit test is related to the ...

2 Answers · Science & Mathematics · 17/07/2012