Issue:
For liquid filled MV Transformers, What is the standard heat rise?

Product Line:
Transformers

Environment:
Classes 7200, 7300, and 7400 MV transformers

Resolution:
The average temperature rise of the windings, measured by the resistance method, shall be [55°C] [65°C] when the Transformer is operated at rated kVA output in a 40°C ambient. The
Transformer shall be capable of being operated at rated load in a 30°C average, 40°C maximum ambient, as defined by ANSI C57.12.00 without loss of service life expectancy.
NOTE: The ambient temperature shall not exceed 40 degrees C, and the average ambient temperature for any 24 hour period shall not exceed 30 degrees C.

Released for: Schneider Electric USA