Electrical Enclosure Cooling
The internal temperature of an electrical enclosure must be closely monitored and controlled in order to protect sensitive equipment housed inside. Electrical equipment is susceptible to high temperatures and can result in shortened life expectancy of components and equipment failure. Unwanted heat can come from internal sources ( the components themselves) and external sources (environmental conditions). There are four main methods for enclosure cooling: air conditioners, thermoelectric coolers, compressed air coolers and air-to-air heat exchangers.
Enclosure air conditioners use chemical refrigerants, compressors, evaporators, condensers and fans to cool the inside of an enclosure. They create a closed loop system for cooling, which circulates the air inside the enclosure without mixing with outside air.
Enclosure thermoelectric coolers are solid-state heat pumps that use the Peltier Effect. This occurs when a direct current (DC) is passed through two different semiconductors, causing one side to get colder while the other side gets hotter. The cold side of the thermoelectric cooler is placed inside the enclosure and the hot side is placed outside the enclosure. Fans are used to circulate cool air throughout the enclosure.
Enclosure compressed air ac coolers are devices that use a compressed, filtered air stream and spin it into a high-speed vortex. This vortex splits the air into a hot stream of air and a cold stream of air. The cold stream is placed into the enclosure which displaces the warm air inside and exhausts it with the hot air stream out of the enclosure.
Enclosure heat exchangers or air to air exchangers use a heat pipe filled with a type of refrigerant liquid that boils when absorbing heat from the hot air of the enclosure. The heated vapor moves to the cooler end of the pipe, which is outside of the enclosure, expelling it into cooler ambient air. The vapor is changed back to a liquid and moves back towards the warmer end of the heat pipe to start the process again.
