Cooper Envirotran transformer

The Cooper Envirotran is a family of liquid-filled transformers from Cooper Power Systems, later part of Eaton, and includes a Solar version built for medium-voltage solar PV applications. Envirotran Solar units come filled with Envirotemp FR3, a biodegradable dielectric fluid made from seed oil, which the maker says extends the life of the insulation. FR3 has a fire point above 300 °C, which the maker contrasts with 155 °C for mineral oil, so pool fires are much less likely. The solar line can be custom-rated for the site's temperature profile, altitude, solar profile and required system life. It is offered as standard step-up units and as dual-secondary designs with 4-winding or 3-winding arrangements. FM Approved versions are built to FMRC Standard 3990 and carry the FM Approved logo on the unit and its nameplate. The approval makes it easy to show compliance with the 2008 NEC Section 450.23 rules for less-flammable liquid-filled transformers, indoors and outdoors. The transformer can also be ordered UL Listed and Labeled and/or UL Classified, which is another route to meeting Section 450.23. When the unit is decommissioned, nearly all of its materials can be recycled or reclaimed, including the core and cabinet steel and the fluid.

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• sentence 3: support check: partial - The passage gives fire point above 300 °C versus 155 °C for mineral oil, but says fire likelihood is nearly nonexistent and long-term risk is minimized, not specifically 'pool fires much less likely'. The pool fire claim is only about field experience. -->