Purpose
An electrical enclosure is a cabinet box designed to house electronic or electrical equipment, mount knobs, displays, and switches. This not only prevents the user from getting shocked but also protects the contents from being damaged by water, sunlight, winds other weather elements. Moreover, Electrical enclosures have a wide array of uses in industrial, commercial, building, and utility applications. Typically, the enclosure is the only part of the equipment or appliance that is visible; meaning that it can be designed to be pleasing to the eye. Even so, NEMA ratings may dictate the design, build, and features of electrical enclosures in hazardous places such as coal mines and petrochemical industries which can limit their aesthetics.
The most common uses include but not limited to:
- Panel boards and distribution boards
- Contactors, circuit breakers, switches and control panels
- Purging and pressurization systems and equipment
- Telephone cabinets
- shield equipment from radiofrequency and electromagnetic
NEMA Ratings Standards
In the US, NEMA (National Electrical Manufacturers Association) provides the guidelines and standards on how electrical enclosures should be designed and built depending on the purpose and where they are to be used. These standards cover submersion, water, and corrosion resistance among others. Some of the classes under NEMA include:
Type 1: These are general purpose electrical enclosures designed to house indoor equipment and appliances. Primarily, they are built to prevent incidental contact with live parts of the equipment that can cause an electrical shock. In addition, they are also constructed to prevent foreign objects such as dirt, dust, and indirect water splashing that could otherwise damage the equipment. Nevertheless, it is important to note that most of them are not dust-tight.
Type 3R: Unlike type 1 enclosures, these are built for both indoor outdoor electrical equipment to provide some degree of protection from ice and falling rain. The design is optimized to prevent the appliance from getting damaged by foreign objects and adverse weather conditions such as rain, ice, and snow. Most come with side and bottom knockouts which prevent water from shorting live parts of the equipment or interfering with its operation under specific conditions. Besides, the design also protects the user from getting into contact with live parts of the appliance that can result to the user from getting an electrical shock. However, despite all the precautions, if the appliance still manages to wear off, Pittsburgh Appliance Repairs firm can help fix it.
Type 4X: According to NEMA, this class of electrical enclosures should be weatherproof (weather tight). Most are designed with stainless steel which provides a higher degree of protection against sleet, snow, and rain, windblown dust, splashing, and directed water. This implies that they can be used when protection from extreme weather conditions is necessary. And since they are built for outdoor applications, they come in an array of types including:
Materials
Electrical enclosures are crafted from a wide array of materials depending on the application and place of use. These include stainless steel, carbon steel, and aluminum.
Stainless steel and carbon steel
These materials are popular for electrical enclosures since they are not only durable but also because they are corrosion, chemical and moisture resistant. Stainless steel is specifically ideal for pharma, medical, and food industry applications since it is non-porous, fungal, and bacterial resistant.
Aluminum
Aluminum is also ideal for its corrosion resistance lightness and durability. It is also suited for harsh weather conditions and where a shield against electromagnetic interference is required