What is the difference between the 80 degreesC, 115 degrees C and 150 degress C, transformer temperature?

Issue:
What are the different transformer temperature rises and the difference between them?

Product Line:
Transformers

Environment:
Low voltage Transformers

Cause:
Understanding temperature rise application and differences

Resolution:
Transformers give off waste heat as a byproduct of their operation as do all electrical devices. The heat generated in transformer operation causes temperature rise in the internal structures of the transformer. In general, more efficient transformers tend to have lower temperature rise, while less efficient units tend to have higher temperature rise.

Transformer temperature rise is defined as the average temperature rise of the windings above the ambient (surrounding) temperature, when the transformer is loaded at its nameplate rating.
Temperature rise is also a rough indicator of transformer efficiency. For example, a transformer with an 80C temperature rise uses 13-21% less operating energy than a 150C rise unit.  In addition, 115C rise Transformers have a 15% continuous overload capacity. 80C rise Transformers have a 30% continuous overload capacity.

Released for: Schneider Electric Canada