E+C August 2018

TRANSFORMERS + SUBSTATIONS

Dry-type transformers are ideal for indoor, underground and marine applications.

ments including self-extinguishing characteristics as well as non-hazardous gas emissions. The transformers are also suitable for transportation, storage and operation at temperatures as low as minus 25°C, meeting Class C2. Multi-layer winding in dry-type transformers – which permits the easy introduction of extra cooling ducts in the coil – also allows the units to safely handle high surge voltages, and to balance surge voltage stress

across the winding. The larger cooling surface area facilitates a uniform temperature dis- tribution.Dry-type transformers can be engineered to operate in very cold climates, as well as in hot and humid regions. The coil support system in these transformers has uniquely developed spacers, which isolate vibrations from the iron core; this reduces noise levels considerably and makes for much quieter operation.

David Claassen is the Managing Director at Trafo Power Solutions.

Low voltage and medium voltage coils frozen during the test procedure.

A cast resin transformer in a test bay.

View of a transformer inside a freeze chamber being tested for C2, E2 and F1 compliance.

Electricity + Control

AUGUST 2018

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