• Cy Cates

Transformer Construction differences Power/Distribution/Industrial

1. Power Transformers Require excellent short circuit strength & dynamic cooling.


Exposure to many short circuits

· Fan cooling increases MVA 167% above base rating. Example: 12/16/20MVA ONAN/ONAF/ONAF.

· Optional LTC (Load Tap Changer) automatically adjusts Voltage output.

Power Transformers have CYLINDRICAL WINDINGS & CRUCIFORM MITERED CORE for maximum short circuit strength & to provide excellent liquid flow which helps convection cooling. (Disc Windings for Voltages 69kV & up)

2. 3 phase Standard Distribution Transformers

Electric Utility pad mounts are the highest volume product segment, which serve commercial, institutions, medical, & manufacturing, can rest daily for 8 to 12 hours. For this Voltage rating, to 35kV, product design & new developments usually come from Pad Mount manufacturers, who also offer substations for the Industrial market.

Standard Distribution Transformers, in the US, are made with wound core & rectangular windings. They function well for most intended loads, but may not be adequate for: 1. loads having high harmonics, special cooling needs, or dedicated motor starting. Some manufactures add end plates to help them pass the Short Circuit Test (not shown).

3. Industrial Transformers

Although smaller & lower primary Voltage, may operate in harsh & hot environments (above 30°C ambient), with little or no rest for months, & high harmonic loads. Downtime can be very costly.

Industrial Transformers will benefit from Power Transformer construction, even at 500kVA . ELTAS OFFERS CYLINDRICAL WINDINGS & CRUCIFORM MITERED CORE for superior performance, motor starting, & excellent cooling. Eltas standard design is elliptical winding with stacked core. Give us a try.

Cy Cates 832 647 4606 cycates@cycates.com www.cycates.com/blog

#distributiontransformer #PowerTransformer #transformer

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