HydroFlo has built "Explosion Proof Panels" for hazardous locations worldwide. All of our panels are built to National Electrical Code (NEC) specifications and are suitable for installation in Class I, II or III Hazardous Locations. Depending on your site specific requirements, we can supply a NEMA 7 explosion proof enclosure or a purged NEMA 4 enclosure.
While both types of panels are suitable for hazardous locations, there are a few basic differences between a NEMA 7 and a purged NEMA 4
Nema 7 panels attempt to contain any possible explosion. NEMA 7 enclosures are cast from heavy duty aluminum so that they cannot create a spark that could possibly ignite the vapors in a hazardous location. These heavy duty panels come with "O" ring gaskets to keep explosive fumes from entering the panel and are designed to contain an internal explosion without igniting the explosive vapors present in the hazardous area.
Purged NEMA 4 panels attempt to keep any explosive fumes from entering the panel. From the exterior they look just like a typical control panel. The difference is that the interior of the enclosure is constantly being purged with either nitrogen or air. This process keeps the panel free of any explosive vapors that may be present in the hazardous area. These purged systems are often required to be equipped with pressure sensors, alarms and automatic shut down functions in the event of the purge system failure.