If the load is 10Kw and power factor has to improve from 0.5
to 0.8,how can we select the capacitor rating
accordingly.Illustrate by showing formula?

Answers were Sorted based on User's Feedback



If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / guest

at 0.5pf Apparent power is 10/0.5=20VA
reactive power = 17.321kVAR.
At 0.8pf
APPARENT POWER =10/0.8=12.5VA
Reactive power=7.5kVAR
So we need to provide (17.321-7.5)=9.821kVAR reactive power
through capacitor to bring of up 0.8 from 0.5.
So we need a capacitor rated for approximately 10kVAR to
achieve the target.
ANS= CAPACITOR RATING 9.821kVAR (approximately 10 kVAR)

Is This Answer Correct ?    10 Yes 2 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / prasad damodar bhoir

kvar= kw (tan phi 1- tan phi 2)
cos phi 1= 0.5, phi 1= cos inverse 0.5= 60
cos phi 2= 0.8, phi 2= cos inverse 0.8= 36.86
kvar= 10 (tan60 - tan 36.86)= 10 (1.73-0.74)
kvar= 9.9

Is This Answer Correct ?    4 Yes 0 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / h salim

Load = 10 kW
cos phi 1 = 0.5
cos phi 2 = 0.8

Rating of capacitor Qc = kW(tan phi 1- tan phi 2 )

Is This Answer Correct ?    3 Yes 0 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / prakash g.r.

Calculation of Required Kvar

Initial or Present Power Factor =Qi,
Required Power Factor = Qd

KVAr= KW(TANQi-TANQd)

Qi=COS-1PFi = Initial Power Factor Angle

Qd=COS-1PFd = Final Power Factor Angle

Is This Answer Correct ?    3 Yes 0 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / ahatesham

at 0.5pf Apparent power is 10/0.5=20VA
reactive power = 17.321kVAR.
At 0.8pf
APPARENT POWER =10/0.8=12.5VA
Reactive power=7.5kVAR
So we need to provide (17.321-7.5)=9.821kVAR reactive power
through capacitor to bring of up 0.8 from 0.5.
So we need a capacitor rated for approximately 10kVAR to
achieve the target.
ANS= CAPACITOR RATING 9.821kVAR (approximately 10 kVAR)

Is This Answer Correct ?    2 Yes 0 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / nagesh.patwari

Kvar = KW * [ tan (cos^-1* Current PF) - tan (cos^-1* Required PF)]

Is This Answer Correct ?    0 Yes 0 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / lohith

kvar=kva*sin

Is This Answer Correct ?    2 Yes 3 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / rk

How did you Calculate Apparent Power=20VA to Reactive power 17.321 KVAR simlarly 12.5VA to 7.5KVAR As the formula is KVAR=KVA/KW

Is This Answer Correct ?    0 Yes 2 No

If the load is 10Kw and power factor has to improve from 0.5 to 0.8,how can we select the capacitor..

Answer / nag

unity powerfactor

Is This Answer Correct ?    0 Yes 5 No

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