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It simply the product of r.m.s current through that conductor and r.m.s voltage across the conductor and the neutral/ground. We can measure the voltage with help of voltmeter and current with help of ammeter.Both these meter measure these quantity in r.m.s mode.
Wiki User
∙ 14y ago
Wiki User
∙ 14y agoPower is typically measured in KVA because this is the vector sum of the real power (kW) and reactive power (KVAR) which are both flowing in the power system. KVA provides the total power flowing, so it is a more useful value in terms of equipment rating and sizing.
Wiki User
∙ 13y agoTo answer this question One needs to Understand ELECTRIC POWER.
Electrical Power has many forms. You will find terms like:- Apparent Power, Reactive Power, Active Power. Note that Power is ultimately Apparent Power.
Apparant Power (True Power) = Reactive (Useless Power) + Active Power (Useful Power).
Now KVA = Apparant Power (True Power)
KW = Active Power (Useful Power)
KVAR = Reactive Power (Useless Power).
KVA is therefore the ultimate Power Term used in Electrical Engineering.
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Why power is measured in terms of kva not in kw in ac supply?
Unlike DC in AC Power is the Product of Voltage*Current*Power FactorP = V*I*PFIn the above expression power factor is a variable quantity which can be different for different circuit hance does not allow you to specify ratings in KW rather then KVA.
What is the power of AC generators measured in kW or kVA?
Yes, you can use both, but watts is more useful; it provides the total amount of power the generator can output.
Is 10 kva supply to 3 phase load is equal to 10kva supply to single phase load?
Yes of course!! 10 kva electrical power is 10 kva electrical power either it would be three phase or single phase. But other factors i.e. current, voltage changes accordingly. Actually this question is quit confusable. Because in 3phase system, if each phase gives 10kva power (single phase power = 10 kva) then 3 phase power will be 10 X 3 = 30 Kva If we go leteratualy towasrds the question, then the asnwer will be - No. becasue 10 kva supply to 3 phase load will be 3phase supply(i.e440V) & 10kva supply to single phase load will be single supply (i.e 250V).
Why maximum demand rating is not expressed in kw?
maximum demand is measured in kva because current drawn is dependent on power factor for the same load and current drawn is calculated with kva
What is the formula to calculate load voltage?
Power requirements are measured in KVA, which stands for Kilo-Volt-Amperes. To calculate the amount of power you require you would use the following formula. KVA = Volts * Amps / 1000
Why power is measured in terms of kva not in kw in ac supply?
Unlike DC in AC Power is the Product of Voltage*Current*Power FactorP = V*I*PFIn the above expression power factor is a variable quantity which can be different for different circuit hance does not allow you to specify ratings in KW rather then KVA.
Why transformers are rated with KVA?
Transformers, like inductors can only handle a specific amount of voltage and current before overheating, with AC or DC input. AC 'real' power delivery from a transformer is measured in kilowatts (kW) which is identical to KVA when "Power factor = 1". In the extreme, with "Power factor =0", a transformer could be fully loaded in terms of KVA, while supply zero 'real' power (kW).
What is the power of AC generators measured in kW or kVA?
Yes, you can use both, but watts is more useful; it provides the total amount of power the generator can output.
Is 10 kva supply to 3 phase load is equal to 10kva supply to single phase load?
Yes of course!! 10 kva electrical power is 10 kva electrical power either it would be three phase or single phase. But other factors i.e. current, voltage changes accordingly. Actually this question is quit confusable. Because in 3phase system, if each phase gives 10kva power (single phase power = 10 kva) then 3 phase power will be 10 X 3 = 30 Kva If we go leteratualy towasrds the question, then the asnwer will be - No. becasue 10 kva supply to 3 phase load will be 3phase supply(i.e440V) & 10kva supply to single phase load will be single supply (i.e 250V).
Why maximum demand rating is not expressed in kw?
maximum demand is measured in kva because current drawn is dependent on power factor for the same load and current drawn is calculated with kva
What are two measures of electricity?
Work and Time; Power = Work/Time
Can we improve generator power factor for increasing active power?
The 0.8 Power Factor provided by generator manufacturers is not the load power factor, but it is the nominal power factor used to calculate the kW output of an engine to supply the power for a particular alternator kVA output. Alternators are therefore designed to supply their rated kVA at 0.8 lagging power factor.
What is the formula to calculate load voltage?
Power requirements are measured in KVA, which stands for Kilo-Volt-Amperes. To calculate the amount of power you require you would use the following formula. KVA = Volts * Amps / 1000
Convert 20 kva to kw?
Your question cannot be answered, unless the power factor of the load is specified. Since true power(measured in watts) is the product of apparent power(measured in volt amperes) and the power factor of the load.So, given your figure of an apparent power of 20 kV.A(not 'kva'*), the corresponding value of true power could (theoretically!) range from20 kW at a power factor of 1.0, to0 kW at a power factor of 0.(*The correct symbol for kilovolt ampere is 'kV.A', not 'kva', and the correct symbol for kilowatt is 'kW', not 'kw'.)
Is the power supply of 45 KVA single phase enough to have 16 PC running at simultaneously in your office?
An ordinary PC has a 300-500 watt power supply. 16 of them would draw 8 kW maximum, and allow 25% extra for peripherals, so that's 10 kW, so a 45 kVA supply would be fine.
How do you calculate 3 phase kWh from amps measured on each phase?
The voltage and current will give the kVA, but the kW depends on the power factor of whatever load is connected to the supply. For a (let's say) 11 kV supply, the voltage from line to neutral is 11,000/sqrt(3) which is 6351 v. The kVA on each phase is 6.351 times the current, and you just add up the three kVA values to find the total. At higher voltges like 11 kV the three currents in the lines are usually very nearly equal.
Why alternators are measured in Kva but not in KW?
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!
