Dry type transformers for outdoor installation

Take the insulation used on the windings of different dry type transformers, for instance.

In many cases, VPI - vacuum pressure impregnation - is the method used to insulate the windings of a dry type transformer.

This process coats the coils in resin, which is then oven-cured to complete the insulation.

However, if you want to place your power transformers in an outdoor setting for the long term, you might want to consider cast coils.

These encase the coil in moulded epoxy resin, which is again put into place using a vacuum.

Cast coil transformers offer greater robustness and higher dielectric strength, making them particularly well suited to harsh operating environments such as outdoor locations.

They can usually withstand spikes in electrical load, as long as they do not last for too long, without suffering the damage that other dry type transformers might experience.

Cast coils also withstand other harsh environments better - including those that are high in dust, moisture, gases or salt.