Frequently asked questions
What is the standard sound level (in dB) of Transformers of various kVA ratings?
FA120629
09 November 2022
Issue:
Sound level can be a factor when specifying Transformers
Product Line:
LV Transformers
Environment:
Applies to Low Voltage Transformers by SquareD/Schneider Electric
Cause:
Transformers of different kVA sizes can generate varying levels of sound when energized
Resolution:
Square D/Schneider Electric Transformers are built to standard sound levels listed in NEMA Standard ST-20. The transformers and corresponding sound levels per NEMA ST-20 are as follows . These can also be found in the Digest :
kVA <> NEMA standard sound level
0 - 9 <> 40dB
10 - 50 <> 45dB
51 - 150 <> 50dB
151 - 300 <> 55dB
301 - 500 <> 60dB
501 - 700 <> 62dB
701 - 1000 <> 64dB