kW is the unit of real power & kVA is the unit of Apparent power.
Apparent Power= real power + reactive power
Besides this,the ratings which we write on a motor or generator is KVA & not KW. B'coz there are two types of losses in a motor or generator- core losses & ohmic losses. Core loss depends upon the voltage applied & ohmic losses depend upon the current flowing & none of these losses depend upon the power factor i.e. Cos@. As we know that
KW power = V * I *Cos@.
But as the losses are independent of the power factor hence we need to calculate only KVA = V*I.
CommentApparent power is the vector sum of real power and reactive power, not the sum.
KVA is the unit of apparent power and KW is unit of active power.
KW is kilowatts, and KVA is kilovoltamps. KW is the apparent power that a normal power meter would measure, while KVA is simply the maximum of the instantaneous product of volts and amps divided by 1000. The difference between these two terms is due to phase angle, which is due to the reactance of the load to an AC power source.
KW (kilowatts) is apparant power, while KVA (kilovoltamps) is true power. They are different when the phase angle between voltage and current is not zero, i.e. when the load is reactive, such as in a motor. The ratio of KW over KVA is Power Factor, and is the cosine of the phase angle between voltage and current. It is zero at a phase angle of 90 degree, which occurs for purely (ideal) inductive or capacitive loads with no resistance in the source or conductors, and it is one for purely resistive loads.
kvar can be calculated as follows the a product KVA andt the sine of the angle between the KVA and KW.
The same way, as you convert Appels to Carrots ........... There is a formula: KVAr = KVA / KW or cos=KW/KVA > Yes, we are treating KW, KVA, & KVAr as the 3 sides in a 90 deg TRIANGLE ! KW= vertical katede KVAr = horizontal katede KVA = hypotenuse
Kilowatts (kW) measure real power, which is the actual power consumed by electrical devices to perform work. Kilovars (kVAR), on the other hand, measure reactive power, which is used to maintain the electric and magnetic fields in inductive and capacitive components. The relationship between kW and kVAR is important in understanding power factor, as they combine to define the apparent power (measured in kVA) in an AC circuit, through the equation: ( \text{kVA}^2 = \text{kW}^2 + \text{kVAR}^2 ). A higher kVAR can indicate inefficiencies in a system, requiring correction to optimize power usage.
{| |- | 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). |}
the difference is that the former is fitted with some type of registration mechanism whereby all the instantaneous reading of power are summed over a definite period of time whereas the latter indicates the value at particular instant when it is read.
kvar can be calculated as follows the a product KVA andt the sine of the angle between the KVA and KW.
kvar can be calculated as follows the a product KVA andt the sine of the angle between the KVA and KW.
The KVAR will be 1249.75, the power factor is .7. KVAR = sqrt [ KVA^2 - kW^2 ]
The same way, as you convert Appels to Carrots ........... There is a formula: KVAr = KVA / KW or cos=KW/KVA > Yes, we are treating KW, KVA, & KVAr as the 3 sides in a 90 deg TRIANGLE ! KW= vertical katede KVAr = horizontal katede KVA = hypotenuse
Kilowatts (kW) measure real power, which is the actual power consumed by electrical devices to perform work. Kilovars (kVAR), on the other hand, measure reactive power, which is used to maintain the electric and magnetic fields in inductive and capacitive components. The relationship between kW and kVAR is important in understanding power factor, as they combine to define the apparent power (measured in kVA) in an AC circuit, through the equation: ( \text{kVA}^2 = \text{kW}^2 + \text{kVAR}^2 ). A higher kVAR can indicate inefficiencies in a system, requiring correction to optimize power usage.
kV is kilovolts, kW is kilowatts, kVA is kilovolt amps and kVAR is kilovolt-amps reactive. A common formula is kVA-squared = kW-squared + kVAR-squared.
For normal power factors (pf=80%), you have 0.8 kW for every kva. In general however, kW = pf x kVA. Where pf is the power factor, it is the cosine of the angular difference between the voltage and the current of a circuit in alternating current circuits.
{| |- | 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). |}
The formula is that kW^2 + kVAR^2 equals kVA^2 or if you prefer, the kW and the kVAR are the two sides of a right angled triangle and the kVA is the hypotenuse. So here you have a 3-4-5 triangle times 140, in other words 420-560-700, and the kVAR is 420.
the difference is that the former is fitted with some type of registration mechanism whereby all the instantaneous reading of power are summed over a definite period of time whereas the latter indicates the value at particular instant when it is read.
It depends on the power factor, which depends on the reactance of the load.For a typical power factor of 0.92, 150 KVAR translates to 383 KVA, which translates to 352 KW.Power factor is the cosine of the phase angle (theta) between voltage and current. KVA times cosine (theta) is KW, while KVA times sine (theta) is KVAR.
Depending upon the connected load ( R, RL, RC or RLC) with a transformer, the power goes ou from a transformer may be of two types: 1. Active Power; measured in kW 2. Reactive Power; measured in kVAR If the rating will be in kW, then kVAR rating would not be accounted but if the rating is in kVA then it is possible for us to calculate the total active and reactive current as well as the powers, at a particular system voltage!