Open Nema 1
Nema 3R
 

Open
Open Lighting Contactors Held are designed to provide a safe, convenient means for local or remote switching of tungsten or ballast lamp loads. They are also suitable for other loads such as low pressure and high-pressure sodium lamp loads and other non-motor (resistive) loads.

Nema 1
A NEMA 1 Enclosure is for general-purpose. It protects against dust, light and indirect splashing but it is not dust-tight. A NEMA 1 Enclosure primarily prevents contact with live parts. It is used indoor and under normal atmospheric conditions.

Nema 3R
A NEMA 3R Enclosure is weather-resistant. It protects against falling dirt. It protects against weather hazards such as rain, sleet and snow, and it is undamaged by the formation of ice. It is used outdoors on ship docks, in construction work, and in tunnels and subways.