Enclosure Pressure, Humidity & Condensation

If an enclosure is not protected from moisture penetration, condensation can accumulate on the components inside the enclosure. Outdoor enclosures can be the most vulnerable to condensation, because they are often installed in environments that have high ambient humidity levels. Condensation can cause damage to electrical components, as well as to the enclosures themselves. Some potential hazards include: corrosion, short circuits, premature breakdown, mold and water drainage issues. Installing devices such as heaters, fans, air conditioners and dehumidifiers can help to manage an enclosure’s internal temperatures. These devices are typically regulated by thermostats and hygrostats, which automatically trigger the fans and heaters when ambient conditions reach a certain temperature or humidity level.

Hazardous Location Breather Enclosure Drains prevent moisture build-up within hazardous location enclosures while maintaining the UL Type rating. Drains are to be used when an enclosure is subject to fluctuations in temperature which can lead to the formation of condensation and a subsequent moisture build-up. These drains allow air within an enclosure to breathe with the surrounding atmosphere, preventing condensation and any potential damage to electrical equipment.

Enclosure pressure compensation are devices that provide slow pressure equalization in tightly sealed enclosures that result from heat generated by electrical equipment within the enclosure and fluctuations of outside ambient temperature.

Enclosure hygrostats are devices that control the operation of a heater, turning it on when a preset relative humidity is exceeded inside of an enclosure. 

Enclosure dehumidifiers protect electrical equipment within an enclosure by removing moisture from the air caused by condensation.

Enclosure pressure purging is a protection method used to remove any internal explosive dust or gases through a purging process, followed by a pressurization of the enclosure with a protective air or inert gas. This results in a positive internal pressure which keeps any external explosive dust or gases from entering the enclosure.