How to calculated capacitor rating both HT
Answers were Sorted based on User's Feedback
Answer / shashikant
connect the LT capacitor to the 3 phase AC suply, measure
the current & line voltage in each phase. Get the reading.
Calculate kVAR using formula kVAR = 1.732*(Avg.Line Voltage)
*(Avg current)/1000
Is This Answer Correct ? | 34 Yes | 6 No |
Answer / rajib
KVAR=KW(tan@1-tan@2)
Where, @1= system power factor, @2= desire power factor
For example. 500KW motor has system power factor 0.8 and we want to improve it 0.95
tan@1=tan cos-1(.8)=0.75
tan@2=tan cos-1(.95)=0.3287
KVAR=500(0.75-0.3287)=210.65=210KVAR
and so on
Is This Answer Correct ? | 19 Yes | 0 No |
Answer / dharmvir prasad
present pf cos @1 = 0.76
desired pf cos @2 = 0.90
@1=cos- 0.76= 40.536
@2=cos- 0.9= 25.842
tan @1=0.855
tan @2=0.484
tan@1-tan@2=0.37
0.37x kw of motor
Is This Answer Correct ? | 17 Yes | 1 No |
capacitance of the capacitor is mentioned in KVAR.
Formula : KVAR = KW*tan@
FOR tan@, First note the power factor & KW without
connecting capacitor.
The noted power factor is in cos@.Convert the cos@ value in
tan@.
for ex. If power factor is 0.6, KW = 200
cos@ = 0.6
cos-1 (0.6) = 53.1
tan (53.1) = 1.333
200*1.333 = 266.6 KVAR
if you use 266 KVAR capacitor, Then the power factor
improves to unity (1.000).
Is This Answer Correct ? | 20 Yes | 12 No |
Answer / giribalaaji
can anyone plz derive the formula for required KVAR ?
Required KVAR= KW* (tan@1-tan@2) i want to know how tan comes in the equation.
Is This Answer Correct ? | 5 Yes | 0 No |
Answer / mukesh tyagi
Above Answer is correct , so i agree with this perfectlty.
Is This Answer Correct ? | 7 Yes | 6 No |
I would like to say that p.f =KW/KVA AND FORMULA IS KVAR =ROOT OF (KVA)SQURE -(KW)SQURE . THIS IS RIGHT ONE FORMULA
Is This Answer Correct ? | 1 Yes | 0 No |
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