What is ONAN/ONAF1/ONAF2 for transformer cooling

Answer Posted / gowhar

The above answer is true.Moreover ,there is a two stage
forced cooling in some of the transformer
(ONAN/ONAF1/ONAF2.on First stage forced cooling(ONAF1) the
MVA rating increses 33% of the actual rating and on second
stage cooling(ONAF1) MVA rating increases to 66% of the
actual rating.

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