NEMA and IP Ratings

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What are NEMA and IP ratings?  What’s the difference?  Let’s first define each acronym: NEMA stands for National Electrical Manufacturers Association. IP stands for Ingress Protection. In our context we are speaking about the various ratings that can be used to describe the environmental protection provided by enclosures.

Many feel that NEMA and IP enclosure ratings are interchangeable and the same.  That’s not true. However, NEMA and IP ratings are similar.  They do share a common objective, that is to define the environmental rating an electrical enclosure is rated for. To be rated for a particular category the enclosure must meet certain standards as determined by testing.

IP ratings refer specifically to the ingress of water or liquids and also solid objects or dust. NEMA covers additional protections including corrosion and protection against gases, The IP and NEMA ratings are not related and there is no conversion.

NEMA RATINGS

NEMA 1: Provides a degree of protection against “incidental contact with the enclosed equipment for indoor enclosures.”

NEMA 2: Provides a degree of protection against “small amounts of falling water and dirt for indoor enclosures.”

NEMA 3: Provides a degree of protection against “windblown dust, rain, sleet, and external ice formation. Intended primarily for outdoor enclosures but also for indoor enclosures.”

NEMA 3R: Provides a degree of protection against “falling rain, sleet, snow, and external ice formation when used outdoors, and for dripping water when used indoors. Typically used for wiring and junction boxed.”

NEMA 3S: Provides a degree of protection against “windblown dust, rain, sleet, and provides operation of external mechanisms when ice laden. Intended primarily for outdoor enclosures but also for indoor enclosures.”

NEMA 4: Provides a degree of protection against “a pressurized stream of water where an occasional washdown or where machine tool cutter coolant is used. For indoor/outdoor use.”

NEMA 4X: Provides a degree of protection against “corrosive materials and caustic cleaners. These enclosures are made of stainless steel, aluminum, fiberglass, or polycarbonate and used for food and beverage or applications where total washdowns with disinfectants will occur repeatedly. For indoor/outdoor use.”

NEMA 5: Provides a degree of protection against “settling airborne dust, falling dirt, and dripping non-corrosive liquids. Intended for indoor/outdoor use. “.

NEMA 6: Provides a degree of protection against “water entry during a temporary submersion at a limited depth. Intended for indoor/outdoor use.”

NEMA 6P: Provides a degree of protection against “water entry during a prolonged submersion at a limited depth. Intended for indoor/outdoor use.”

NEMA 12: Provides a degree of protection against “falling dirt, dripping non-corrosive liquids, airborne contaminents and non-pressurized water and oil. These enclosures have no knockouts and are used for indoor applications such as automation control, drives systems, packaging, material handling and manufacturing applications.”

NEMA 12K: Provides a degree of protection against “dust, falling dirt, dripping non-corrosive liquids (except at knockouts). These enclosures with knockouts are used for indoor use.”

NEMA 13: Provides a degree of protection against “dust, spraying of water, oil and non-corrosive coolant. Intended for indoor use.”

IP RATINGS

IP ratings use a 3 character system. The rating is preceded by the letters IP.  The next following character indicates the Solids protection rating, the following character indicates the Liquids protection rating, and the last character is used only to indicate High Pressure Testing.

EXAMPLE: IP69K – Solids protection rating 6, Liquid protection rating 9 and K indicates high pressure service rating.

IP RATINGS FOR SOLIDS

Rating 0: No protection from ingress of objects.

Rating 1: Protection from objects larger than 50mm. No ingress of objects larger than 50mm (1.97″), i.e. hands, but not fingers.

Rating 2: Protection from objects larger than 12.5mm. No ingress of objects larger than 12.5mm (0.49″), i.e. fingers or similar.

Rating 3: Protection from objects larger than 2.5mm. No ingress of objects larger than 2.5mm (0.098″), i.e. screwdriver or similar.

Rating 4: Protection from objects larger than 1mm. No ingress of objects larger than 1mm (0.039″), i.e. wires, large bugs and similar.

Rating 5: Protection from limited dust ingress protection. No ingress of most dust particles but not complete ingress.

Rating 6: Protection from full dust ingress. No ingress of dust (dust tight). Surpasses previous protection limits.

IP RATINGS FOR LIQUIDS

Rating 0: No protection from ingress of liquids.

Rating 1: Protection from straight water drops. No vertical water dripping ingress (i.e. 1mm rainfall/min).

Rating 2: Protection from water dripping at 15 degree angle. No water drop ingress at 15 degree angle (i.e. 3mm rainfall/min).

Rating 3: Protection from water dripping at 60 degree angle. No water spray ingress at any angle up to 60 degrees (i.e. water spray nozzle).

Rating 4: Protection from water splash, all directions. No water splash ingress from any angle.

Rating 5: Protection from water jets. No ingress from a 4.4psi (0.3bar) water jet at 3m distance from any angle.

Rating 6: Protection from powerful water jets. No ingress from a 14.5psi (1bar) water jet at 3m distance from any angle.

Rating 6K: Protection from high power water jets. No ingress from a 145psi (10bar) water jet at 3m distance from any angle.

Rating 7: Protection from up to 1m water immersion. No ingress from immersion of lowest part up to 1000mm below water surface.

Rating 8: Protection from over 1m water immersion. No ingress from immersion of lowest part up to 3m below water surface.

Rating 9K: Protection from high pressure and temperature water jets. No ingress up to 1100psi to 1450psi (80bar to 100bar) close range water jet pressure with water up to 176 degrees F (80 degrees C). Surpasses previous protection limits.

 

Sterling Systems & Controls is a UL certified control panel manufacturer. We understand these issues and ratings. If you have any questions please contact us at sci@sterlingcontrols.com or 815-625-0852.