KW vs. KVA

[DouginMB]

I'm an HVAC engineer and work mostly with KW's when specifiying power loads. I have seen loads referenced in terms of KVA. What is the difference? Is there a simple conversion?

 

[jghrist]

kVA = kilovolts times amperes = kW/pf

 

[mekanicles]

DouginMB;

W = Active Power
VA = Apparent Power

pf = W/VA ; pf is the power factor of the system or equipment (power efficiency). Hope this help you...

 

[piterpol]

Kw = (Kva)cos(b), where b is the angle between the current and the voltage and cos(b) is the active power factor (pf). Also, Kvar = (Kva)sin(b), where sin(b) is the reactive power factor.

 

[moturcu]

KW is "used" portion of KVA.
KVAR is the "circulating" portion of KVA.
A factor which is called as power factor determines this sharing. Less circulating energy(kVAR) results more usable energy(kW). Because their vectoral sum (KVA) is constant for any given machine.