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17 comments
Anonymous Poster

KVA To KW conversion

08/23/2008 1:33 AM

how to convert KVA to KW ? let me know the formula. Rgrds Prithvi

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Associate

Join Date: Jun 2007
Location: Sacramento, CA
Posts: 28
#1

Re: KVA To KW conversion

08/23/2008 2:33 AM

you're question is too vague.

fundamentally, kva, kw and kvar are all parts of the power triangle.

If you notice, you would need at least the angle or the kvar to find. also, you need the pf of your load

pf = cosΘ

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#3
In reply to #1

Re: KVA To KW conversion

08/24/2008 12:16 AM

And I always thought the power triangle was Government, Banking and Corporations. The one with the guns carry the most power.

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Guru
Engineering Fields - Marine Engineering - New Member

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#2

Re: KVA To KW conversion

08/23/2008 4:19 AM

I agree with what GISdude has said, but to answer your question in mathematical terms KW = KVA * pf. where pf = the power factor which is cosØ, as explained by GISdude.

Regards JD.

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#4

Re: KVA To KW conversion

08/24/2008 2:30 AM

A less scientific and more practical answer, assuming you are simply comparing a generator set rating : kVA x 0.8 = kW in every common generator name plate today. Manufactures assume a common power factor of 0.8 when they rate their generators so outside USA suppliers use kVA ratings due to their culture and inside USA we use kW ratings since the driver size is based on kW, not kVA (our culture). Some special generators have different power factor ratings to get different sub-transient reactance values but just look on the name plate and you will see kVA, (or kW) power factor as a decimal such as 0.8 and the rest is math. So kW/0.8 = kVA and kVA x 0.8 = kW.

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Anonymous Poster
#17
In reply to #4

Re: KVA To KW conversion

01/19/2011 2:06 PM

Thanks for the help.

MAJ Payson

Logistics, CSJFTC

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Anonymous Poster
#5

Re: KVA To KW conversion

08/24/2008 6:16 AM

Its the same a 50VA transformer is the same as a 50W transformer.

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Guru
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#7
In reply to #5

Re: KVA To KW conversion

08/24/2008 3:34 PM

Wrong. Please don't post if you have no idea what you are talking about.

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Anonymous Poster
#10
In reply to #7

Re: KVA To KW conversion

08/25/2008 7:28 AM

please post the answers when u hve great ideas of quetion,

this will be good for all of us to improve our knoledge and skills,

the perfect answer is to convert kva into kw,

just muliply kva to power factor and u will get kw,

kva=v x i

kw=v x i cosQ (where q is angle between voltage and currentor power factor)

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Anonymous Poster
#15
In reply to #5

Re: KVA To KW conversion

10/13/2009 6:35 AM

you don't know what you are talking about dude

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Guru
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#6

Re: KVA To KW conversion

08/24/2008 9:37 AM

If you read the documentation provided by the generator manufacturer, you will generally find a note that, for a power factor greater than 0.8, the generator must be derated. By rating the generator in kW at .8 PF, it sounds like a bigger unit.

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Participant

Join Date: Aug 2008
Posts: 2
#8

Re: KVA To KW conversion

08/25/2008 2:49 AM
  • apparent power of a load is given by V*I but the active power of an equipment is given by V*I*cosØ, which includes the power factor of that load.
  • S=V*I , S-apparent power,V-voltage,I-current

P=V*I*cosØ P-active power,V-voltage,I-curent and cosØ-power factor of that load

So just by multiplying the apparent power (kVA) with the power factor you will be able to get your active power (kW)

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Commentator
Engineering Fields - Power Engineering - Projects Engineer

Join Date: Aug 2008
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#9

Re: KVA To KW conversion

08/25/2008 3:25 AM

KVA is the product of volts X current over one thousand .i.e for eg. if the volt is 230 and current flowing is 20 Amps than the KVA is 230 X 20 = 4600/1000 =4.6KVA (apparent power)to covert it to power (KW) you need to know the cos, angle (PF) of the supply for most practicle purposes it is assumed to be 0.8 cos.

so if we assume 0.8 PF than the KW will be 4.6 X 0.8 =3.7KW

hope that is understood now.

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Anonymous Poster
#11

Re: KVA To KW conversion

08/25/2008 12:21 PM

Just to shine a little light on technical terms. We generally kid ourselves about our yearly salary (gross salary on your pay stub), which is what we supposedly earn. We can think of this as KVA, the gross power a source is capable of delivering. After deductions, mainly taxes for some, or alimony for others, we end up with a net pay, much less than expected. This will be the KW, the real power usage. Some deductions are inevitable, it come with the territory, such as reactive losses due mainly to windings when powered by AC. Your net pay is hopefully a high percent of your gross, 66% at best. The power factor similarly represent the percentage of real power delivered from a gross power source, and it depends on the makeup of load (resistive-reactive) not your ex-spouse's expenses.

As others mentioned already KVA * PF = KW

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Power-User

Join Date: Feb 2008
Location: Waterford, Ireland
Posts: 110
#16
In reply to #11

Re: KVA To KW conversion

05/12/2010 12:41 PM

What a long winded load of analogical nonsense. True power V Apparent power, KW V KVA is short and sweet.

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Participant

Join Date: Aug 2008
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#12

Re: KVA To KW conversion

08/31/2008 4:00 AM

simple

if u know power factor for that equipment multiply to kva rating u will get

kw rating

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Anonymous Poster
#13

Re: KVA To KW conversion

01/10/2009 3:42 PM

500kva to primre amp

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Anonymous Poster
#14

Re: KVA To KW conversion

04/10/2009 8:50 AM

Did you all remember to carry the 1?

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