Monday, August 18, 2008

ENCLOSURE CLASSIFICATIONS

Industry Standards
Enclosure Types for All Locations
National Electrical Manufacturers Association (NEMA Standard 250)
NEMA/EEC to IEC

TYPE Intended Use & Description

Type 1 General purpose enclosures are suitable for general purpose application indoors, where atmospheric conditions are normal. These enclosures serve as protection against falling dust, but are not dust tight.

Type 2 Drip tight (indoor) enclosures are similar to NEMA 1 enclosures, with the addition for drip shields, and are suitable for application where condensation may be severe, such as that encountered in cooling rooms or laundries.

Type 3 Dust, rain proof and sleet resistant enclosures provide proper protection against windblown dust and weather hazards such as rain, sleet or snow. They are suitable for applications outdoors on ship docks, canal locks, construction work, and for applications in subways and tunnels; use indoors where dripping water is a problem.

Type 3R Dust, rain proof and sleet resistant enclosures provide proper protection against falling dirt and weather hazards such as rain, sleet or snow. They are suitable for applications outdoors on ship docks, canal locks, construction work, and for applications in subways and tunnels; use indoors where dripping water is a problem.

Type 4 Water tight enclosures are suitable for dairies, breweries, etc., where the enclosure may be subjected to large amounts of water from any angle. (They are not submersible)

Type 4X Corrosion resistant enclosures satisfy the same requirements as NEMA 4; in addition they are suitable for food processing plants, dairies, refineries, and other industries where corrosion is prominent.

Type 6 Submersible enclosures are suitable for application where the equipment may be subject to submersion, such as quarries, mines, and manholes. The enclosure design will depend upon the specified conditions of pressure and time.

Type 9 Hazardous location enclosures - Class II, Group E, F or G. These enclosures are designed to meet the requirements of the "Canadian Electrical Code" Part I for Class II hazardous locations, and CSA codes section 18 Class II Group E,F, and G.
Class II Group E - atmosphere containing metal dust
Class II Group F - atmosphere containing carbon black, coal, or coke dust.
Class II Group G - atmosphere containing flour, starch or grain dust.

Type 12 Industrial use enclosures are oil tight. Hammond type 12 enclosures meet JIC standard and also satisfy requirements of NEMA.

Type 13 The cover is held in place with screws, bolts or other suitable fasteners, with a continuous gasket construction. The fastener parts are held captive when the door is opened. There are no holes through the enclosures for mounting or attaching controls inside the enclosure, and no conduit knock-outs or openings. Mounting feet, brackets, or other mounting means are provided. These enclosures are suitable for application to machine tools and other industrial processing machines where oil, coolants, water, filings, dust or lint may enter, seep into or infiltrate the enclosure through mounting holes, unused conduit knock-outs, or holes used for mounting equipment with the enclosure.

The preceding descriptions are not intended to be complete representations
of the National Electrical Manufacturers Association standards for enclosures.
Underwriter Laboratories Inc. (UL 50 and UL 508)

TYPE Intended Use and Description (Approximate IP equivalents)

Type 1 Indoor use primarily to provide protection against contact with the enclosed equipment and against limited amount of falling dirt (IP30).

Type 2 Indoor use to provide a degree of protection against limited amounts of falling water and dirt (IP31).

Type 3 Outdoor use to provide a degree of protection against windblown dust and windblown rain; undamaged by the formation of ice on the enclosure (IP64).

Type 3R Outdoor use to provide a degree of protection against falling rain and sleet; undamaged by the formation of ice on the enclosure (IP32).

Type 3S Outdoor use to provide a degree of protection against windblown dust, rain and sleet; external mechanisms remain operable while ice laden.

Type 4 Either indoor or outdoor use to provide a degree of protection against falling rain, splashing water, and hose-directed water; undamaged by the formation of ice on the enclosure(IP66).

Type 4X Same as type 4 except this one is corrosion resistant (IP66).

Type 6 Indoor or outdoor use to provide a degree of protection against entry of water during temporary submersion at a limited depth; undamaged by formation of ice on the enclosure.

Type 6P Indoor or outdoor use to provide a degree of protection against entry of water during prolong submersion at a limited depth.

Type 11 Indoor use to provide by oil immersion a degree of protection of the enclosed equipment against the corrosive effects of corrosive liquids and gases.

Type 12/12K Indoor use to provide a degree of protection against dust, falling dirt, fiber flyings, dripping water, and external condensation or dripping of non corrosive liquids (IP65).

Type 13 Indoor use to provide a degree of protection against lint, dust seepage, external condensation and spraying of water, oil, and non corrosive liquids (IP65).

If there is anything you would like to add or if you have any comments please feel free to email at electrical_engineer@alriyadh.cc

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