nVent Hoffman Commercial Boxes and Enclosures
nVent Hoffman commercial boxes and enclosures include pull and junction boxes, wall mounted/pad mounted enclosures and utility cabinets and splitters.
Junction boxes are electrical enclosures that house one or more wiring connections. The boxes are designed to protect the connections from environmental conditions and accidental contact. They can be made of plastic (ABS or polycarbonate) or metal (stainless steel or aluminum). Plastic junction boxes generally house non-metallic cables and are resistant to extreme temperatures, UV exposure and high-impacts. Metal junction boxes generally house metal conduit and metal-sheathed cable that require grounding. Almost all junction boxes have cutouts for cables and conduits to enter and exit the enclosure and have hinged covers for easy access to the components for maintenance and troubleshooting. Junction boxes can be mounted on walls or on mounting pads with the use of mounting feet and flanges.
Wall mounted/pad mounted enclosures can be used to protect drives, controls and power distribution components from harsh environmental conditions. The operating environment and application will determine the type of material for the enclosure. Key and padlocking options are available for added security.
nVent Hoffman’s off-the-shelf utility cabinets and splitters meet the requirements of local utilities. They have been designed and tested to meet Canadian standards and regulations, as well as other specific utility requirements. Hoffman carries a wide range of CT cabinets and terminal boxes that safely enclose instrument transformers and branch circuits.
Enclosure Selection Basics
Electrical enclosures are cabinets that are designed to house electrical components. Their main function is to protect the components, as well as to protect the operators from electrical hazards. Enclosures are typically made of solid plastics, fiberglass and metal materials, such as carbon steel, stainless steel and aluminum.
One of the most important things to consider when selecting an electrical enclosure is the NEMA rating. NEMA stands for National Electrical Manufacturer Association. They have developed a rating system which determines the types of environments an electrical enclosure can be used in.
NEMA 1 and a NEMA 12 enclosures
Both of these enclosures are intended for indoor use only. They are both dust resistant. The NEMA 12 enclosure is rated for damp environments. The NEMA 1 is rated only for dry environments.
NEMA 4 and NEMA 4X enclosures
Both of these enclosures can be used indoors as well as outdoors. They are both dust resistant. They are also water resistant and corrosion resistant. NEMA 4X has an extra layer of corrosion resistance.
NEMA 7 enclosures
This is a more specific type of enclosure that is rated for use in hazardous environments. It is rated to contain an explosion within the enclosure and not cause any sort of external hazard.
Size
When selecting the size of an enclosure, it is important to consider the following: how much space will the electrical components occupy, how much space is needed around each component, is there enough room to run all of the wires and how much space is needed outside of the enclosure?
Temperature
When selecting an enclosure, it is important to consider both the ambient temperature and the temperature that is generated inside of the enclosure. When an enclosure is located outside in direct sunlight, that heat can be transferred inside the enclosure. Also, each component inside of the enclosure generates a certain amount of heat.