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Because the manufacturer has no way of knowing the power factor of load it will be supplying. So its rating is always the product of its rated voltage and its rated current, which is in volt amperes.

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Transformer rating is expressed in?

VA or KVA or MVA


What are transformers rated?

A transformer's capacity is rated in volt amperes(V.A). This is the product of the secondary winding's current rating and voltage rating.


What is the current of a 45 kva transformer?

Presumably, you are asking what is the rated secondary current for a 45 kV.A (not 'kva') transformer? The answer depends on its rated secondary voltage. To obtain the rated secondary current, you divide the (apparent) power rating by its secondary rated voltage.


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 transformer rating is called kva not kw?

Transformers are rated in KVA because that is a more accurate way to measure their capacity requirements. KWH is apparent power, while KVA is true power, and the ratio between them is power factor. The power factor is a function of the load, and not the transformer, so a poor power factor would make KWA look less to the transformer while, in fact, the true power, if not met by the transformer, could overload the transformer.

Related Questions

How do you Convert va to kva?

a kva is 1000 vaK is kilo, which means 1000 similar to how a kilometer is 1000 metersTransformers are usually rated in KVA, so a 45 KVA Transformer is a 45 000 VA Transformer


Does a transformer convert the current from 240 volts to 120 volt?

Transformers are rated in KVA or VA (volt-amps). They transform voltages from one value to another. The current in a transformer is inverse to the voltage. This is why transformers are rated in KVA and smaller ones in VA.


Transformer rating is expressed in?

VA or KVA or MVA


What are transformers rated?

A transformer's capacity is rated in volt amperes(V.A). This is the product of the secondary winding's current rating and voltage rating.


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 kva rating of single phase transformer?

This is the rated output of the transformer, obtained by multiplying the rated secondary voltage by the rated secondary current. And it's 'kV.A', not 'kva'.


Why transformer rated kva?

The correct symbol for kilovolt amperes is 'kV.A, not kva. A volt ampere is the product of the transformer's secondary rated voltage and its rated current. It is not rated in watts, because the transformer designer has no idea what sort of load is to be applied to the transformer, and it is the load that determines the amount of watts, not the transformer.


Why a transformer is rated as KVA?

A transformer has separate ratings for voltage and current. The voltage limit is set by the maximum magnetic flux-density in the iron core. The current limit is set by the resistance of the copper wire in the windings. Multipy the two together to get the VA rating, divide by 1000 to get kVA.


What is the current of a 45 kva transformer?

Presumably, you are asking what is the rated secondary current for a 45 kV.A (not 'kva') transformer? The answer depends on its rated secondary voltage. To obtain the rated secondary current, you divide the (apparent) power rating by its secondary rated voltage.


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.


480 transformer to 120 ac current what is the kva on transfomer?

The kVA rating will be listed on the transformer's nameplate, which is usually on the front of the transformer. The 480v to 120v is irrelevant, because many transformers with different kVA ratings convert 480 volts to 120 volts. The kVA ratings can be different and thus affect the rated current through the transformer.


What is the full load current for1600 kva transformer?

It depends on the rated voltage. Take 1600 KVA and divide by KV, and you will get A.