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ikram_dp
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why is the Rating of Transformer is in KVA and not in KW?
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KVA stands for kilovolt-ampere and is a unit of apparent power, while KW stands for kilowatt and is a unit of real power. In simple terms, KVA measures the total amount of power that a transformer can handle, while KW measures the actual usable power output. KVA takes into account the reactive power that is lost due to the transformer's internal resistance, while KW only measures the power that is actually converted into usable energy.
KVA is used as the standard unit for rating transformers because it takes into account the total power capacity of the transformer, including both real and reactive power. This is important because transformers are designed to handle both types of power, and using KVA allows for a more accurate measurement of the transformer's capabilities.
The conversion from KVA to KW depends on the power factor of the transformer. If the power factor is known, the conversion can be done using the formula KW = KVA x power factor. If the power factor is not known, a general rule of thumb is to assume a power factor of 0.8, which would make the conversion KW = 0.8 x KVA.
The ideal KVA to KW ratio for a transformer varies depending on the specific application. In general, a ratio of 1:1 is considered good, meaning that the transformer can handle the same amount of KVA and KW. However, some applications may require a higher or lower ratio, so it is important to consult with a professional to determine the best ratio for your specific needs.
Yes, a transformer can be overloaded if only KVA is considered. This is because KVA does not take into account the power factor or the actual usable power output. If the power factor is low, the transformer may not be able to handle the full KVA rating, leading to overload and potential damage. It is important to consider both KVA and KW when rating transformers to ensure proper usage and avoid overloading.