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Can I use Primary Taps to change the Secondary voltage output on a Low Voltage Transformer?

Issue:
Usage of existing Taps on Transformer Primaries

Product Line:
LV Transformers

Environment:
Applies to Low Voltage Transformers by SquareD/Schneider Electric

Cause:
Need to change Secondary voltage on Transformers to higher or lower levels.

Resolution:
Taps provided on the Primary of SquareD/Schneider Electric Low Voltage Transformers are there solely for the purpose of compensating for too high or too low incoming source voltages.  They are a means of obtaining the proper Secondary voltage(s) that the Transformer is designed for, when incoming source voltage is not at the rated nominal value.   Taps should not be used for the purpose of changing the Secondary voltage(s) to different levels than those for which the Transformer is designed.  For example, for a Three Phase Transformer with a 480V Delta Primary and a 208Y/120V Secondary.  Taps with design voltages lower that 480V, (such as the 456V or 432V Tap)  should not be energized with a full 480V source in order to "boost" the secondary voltage of the Transformer to a level higher than the design value of 208Y/120V . Doing so can dramatically increase the internal heat generated within the Transformer over design levels, leading to vastly shortened life and possible destruction of the Transformer windings.
 
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