Why transformer is rated in KVA and not in KW?

Why transformer is rated in KVA and not in KW?

The power delivered by the source is given by √3*V*I*cosΦ. For the same value of current, the power delivered depends on the power factor of the load i.e. cosΦ. Transformer being the appliance that provide power to the load, manufacturers do not know the type of load that will be connected to the transformer. So they simply design and rate the transformer according to its maximum voltage and current that it can safely handle considering unity power factor.

Transformer rating KW नभई किन KVA हुन्छ ?

कुनै पनि transformer ले supply गर्ने power भनेको √3*V*I*cosΦ. Voltage र current लाई constant मन्ने हो भने transformer ले supply गर्ने power भनेको power factor ( cosΦ )मा depend हुन्छ! Transformer भनेको load लाई Power supply गर्ने यन्त्र भएको हुनाले एस्मा कस्तो load जोदिन्छ transformer बनौने कम्पनी लाई थाहा हुन्न । त्यसैले कम्पनी ले स्वत transformer ले धन्न सक्ने maximum voltage र current को आधर मा rating गरेको हुन्छ । यो बेला power factor को मान १ हलेर rating निकलेको हुन्छ । कस्तो load जोदिने थाहा नभएर नै KVA मा हालेको हुन्छ rating.

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