Bison Profab products

Nema 3R enclosures are designed very similar to Nema 3 enclosures, however 3R enclosures can be ventilated. Enclosure ventilation is typically accomplished through the use of louvered openings to filter the air within the enclosure, and necessary for a vented battery enclosure. When ventilated, the degree of protection provided by Nema 3R enclosures against windblown dust is diminished. However, this can be offset through the use of screens and/or air filter material placed in the back of the louvered openings.