Why are transformers rated in kVA and not amperage?

Transformers are rated in kVA because the losses occurring in the transformers are independent of power factor. KVA is the unit of apparent power. It is a combination of real power and reactive power. Transformers are manufactured without considering the load being connected.

Why transformers and alternators are rated with kVA?

If we connect inductive or capasitive load (When power factor is not at least unity), The output would differ than as there are losses occurs due to low power factor. For this reason, KVA is an apparent power which does not take in to account the PF (Power factor) instead of KW (Real Power). And kVA = KW / Cos θ.

Why transformer is rated in kVA and motor in KW?

As, the copper loss or I2R loss depends on the current and the iron or core loss depends upon the voltage of the transformer. Thus, the total losses in a transformer depend upon volt-ampere (VA) only and not on the power factor of the load. That is why the transformer rating is given in kVA and not in kW.

Why is the alternator output rated in volt-amperes rather than watts?

The reason for which the transformers and alternator (synchronous generators) are rated in volt-amperes instead of watts is that manufacturer does not know at what power factor does these equipments are going to operate. This is the rated full load current of an alternator.

What does the kVA rating of a transformer mean?

kilovolt-amperes
The kVA unit represents kilovolt-amperes, or 1,000 volt-amperes. A transformer with a 1.0 kVA rating is the same as a transformer with a 1,000 VA rating and can handle 100 volts at 10 amps of current.

What is the rating of transformer?

A transformer with a 100 VA rating, for instance, can handle 100 volts at one ampere (amp) of current. The kVA unit represents kilovolt-amperes, or 1,000 volt-amperes. A transformer with a 1.0 kVA rating is the same as a transformer with a 1,000 VA rating and can handle 100 volts at 10 amps of current.

How harmonics in transformer shortens life of a transformer?

Harmonics also induce additional eddy current and hysteresis losses in transformer cores. These losses cause abnormal temperature rise in the transformer, which accelerates the degradation of transformer insulation, ultimately leading to a shortened life span for the equipment [9] .

How are transformers rated?

Transformer ratings are measured in volt-amperes (VA) or kilovolt-amperes (WA). Engineers rate power transformers according to the maximum output voltage and current they deliver. A transformer with 12 V output, capable of providing up to 10 A of current, has a VA capacity of 12 V x 10 A, or 120 VA.

How alternators are usually rated?

The rating of alternator generally given in the order of VA or kVA or MVA.