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My transformer enclosure is too hot

UL and CSA standards strictly regulate the highest temperature that an enclosure can reach. For ventilated transformers, the temperature of the enclosure should not increase by more than 50 degrees C in a 40 degrees C ambient full rated current. For encapsulated transformers, the temperature of the enclosure should not increase by more than 65 degrees C in a 25 degrees C ambient full rated current. This means that it is permissible for the temperature of the enclosure to reach 90 degrees C (194 degrees F). Although this temperature is very warm to the touch, it is within the allowed standards. A thermometer should be used to measure enclosure temperatures, not your hand.