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Transformer rating is based on the maximum temperature a transformer can run at. This temperature is dictated by the amount of current flowing through the transformer windings. This is why Transformers are rated in KVA (voltage * current), not kW - it doesn't matter what the phase relationship is between voltage and current, just the magnitude of the current.
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Why transformer rating is mentioned in kva rather than kw?
Because its measured in kilo volt amps which is the actual reflection of current flowing through the windings. if kw were used as a rating, then it would have to be stated at some power factor
What is the difference between KVA and KW of a transformer?
Transformer power is given by P=V*I which takes the unit of KVA while that of KW has energy term which is not produced by the transformer.It only steps up or down the voltage.Answer:In a pure D.C. circuit, KW = KVA. However, in any A.C. circuit, there is real power {KW} and apparent power {KVA}, due to the voltage and current being out of phase. Power Factor is the ratio of KW to KVA. Transformers are rated in both KVA and PF. Multiplying the transformer KVA rating times the PF will yield KW.A transformer has separate ratings for maximum voltage and maximum current. Multiply the two together and that is called the VA rating, or kVA for larger transformers. So the transformer rating is independent of the power factor of the load.
Why is a motor rated in KW's and a transformer rated in?
The mechanical load of a motor determines the necessary output power rating of an electric motor. As mechanical loads are defined in terms of watts (or, in North America, horse power), then motor's output must be rated in watts, too.The so-called 'power' rating of a transformer is determined by the rated voltage and the rated current of its secondary winding. The product of these two quantities is the transformer's rated 'apparent power', expressed in volt amperes.Incidentally, the symbol for "kilowatts" is "kW", not"KW's"!
Why transformer is measured in kva?
The rating of the machine (kva or kw) depends upon the power factor, since the load power factor to which the transformer is supplying power is not known, it may be capacitive, inductive, or resistive that is why its rating is in kva not in kw.
What is the use of transformer utilisation factor?
It tells us how much is the transformer utilised in a given process. For a rectifier,TUF =(D.c.power delivered to the load)/(power rating of transformer secondary)
Why the rating of a transformer is given in kVA?
The rating of a transformer follows the two magnitudes that affect its operation; Volts and Amperes. The other, more popular parameter (kW) is not used on transformers because it depends on connected load Power Factor.
How do you calculate the dc circuit breaker rating for a given kw?
the given kw Divide by the your voltage
Why transformer rating is mentioned in kva rather than kw?
Because its measured in kilo volt amps which is the actual reflection of current flowing through the windings. if kw were used as a rating, then it would have to be stated at some power factor
What is the difference between KVA and KW of a transformer?
Transformer power is given by P=V*I which takes the unit of KVA while that of KW has energy term which is not produced by the transformer.It only steps up or down the voltage.Answer:In a pure D.C. circuit, KW = KVA. However, in any A.C. circuit, there is real power {KW} and apparent power {KVA}, due to the voltage and current being out of phase. Power Factor is the ratio of KW to KVA. Transformers are rated in both KVA and PF. Multiplying the transformer KVA rating times the PF will yield KW.A transformer has separate ratings for maximum voltage and maximum current. Multiply the two together and that is called the VA rating, or kVA for larger transformers. So the transformer rating is independent of the power factor of the load.
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!
Why is a motor rated in KW's and a transformer rated in?
The mechanical load of a motor determines the necessary output power rating of an electric motor. As mechanical loads are defined in terms of watts (or, in North America, horse power), then motor's output must be rated in watts, too.The so-called 'power' rating of a transformer is determined by the rated voltage and the rated current of its secondary winding. The product of these two quantities is the transformer's rated 'apparent power', expressed in volt amperes.Incidentally, the symbol for "kilowatts" is "kW", not"KW's"!
Why transformer is measured in kva?
The rating of the machine (kva or kw) depends upon the power factor, since the load power factor to which the transformer is supplying power is not known, it may be capacitive, inductive, or resistive that is why its rating is in kva not in kw.
Why transformer is read in rating KVA but not KW?
Transformers are rated in KVA which is equivelant to "apparent power". Loads, {such as heaters, lamps, etc.} are rated in KW which is equivelant to "real power". Things such as power factor and transformer efficiency account for the diifference between the two values. KW's are what the load requires and KVA's are the values of the input power required in order to serve a given KW load. Unfortunately the utilities charge for KVA not KW. It's not too unlike a glass of beer. The enjoyable part is the beer itself. However, you pay for both the beer and the foam at the top of the glass.
Why transformer are rated in kVA instead of KW?
Transformers are rated in VA or kVA. That is because the voltage is limited by the power loss in the magnetic core, and the current is limited by the power loss in the resistance of the windings. The rated voltage times the rated current gives the transformer's rating in kVA.
What is the minimum load have to go for a new transformer?
All transformers have a power rating given in kVA which determine the maximum load that can be connected to that transformer.
What is the use of transformer utilisation factor?
It tells us how much is the transformer utilised in a given process. For a rectifier,TUF =(D.c.power delivered to the load)/(power rating of transformer secondary)
What is TUF for half wave rectifier?
It indicate how well the input transformer is being utilized. It is given by the ratio of DC output power to the AC power rating of Transformer.
