IP & NEMA Klassifizierung

IP / Ingress Protection Rating & NEMA Equivalent Information (helpful information only, detailed reference should be taken from an appropriate agency)

An IP number contains two numbers (i.e. IP65) in most instances which relate to the level of protection provided by an enclosure or housing.

Solids

The first number relates to protection from solids as follows:

Liquids

The second number relates to protection from liquids as follows:

Example: IP66 = Dust tight and protected against heavy water jet spray

NEMA (National Electrical Manufacturers Association) ratings can be approximately compared to those of the IP system as shown below. Other factors such as corrosion protection are involved in the NEMA system, please refer to official documentation for details.

NEMA 1 = IP10 NEMA 2 = IP11 NEMA 3 = IP54 NEMA 4 = IP56 NEMA 4X = IP66 NEMA 6 = IP67 NEMA 12 = IP52 NEMA 13 = IP54

Understanding IP and NEMA Ratings

The protection of enclosures against ingress of dirt or against the ingress of water is defined in IEC529 (BSEN60529:1991). Conversely, an enclosure which protects equipment against ingress of particles will also protect a person from potential hazards within that enclosure, and this degree of protection is also defined as a standard.

The degrees of protection are most commonly expressed as "IP" followed by two numbers, e.g. IP65, where the numbers define the degree of protection. The first digit (Foreign Bodies Protection)shows the extent to which the equipment is protected against particles, or to which persons are protected from enclosed hazards. The second digit (Water Protection) indicates the extent of protection against water. The wording in the table is not exactly as used in the standards document, but the dimensions are accurate.

The first digit in the rating is the protection against contact and foreign bodies. The second digit in the rating is the water protection factor. The third digit in the impact protection factor It is normally displayed in the format below.

IP s l (i)

s = solids, l=liquids and i= impact (optional)

First Index - Foreign Bodies Protection, Solids

Second Index - Water Protection, Liquids

Third Index - Impact Protection, Impact

Examples:

NEMA Ratings

There are many NEMA ratings available for enclosures. Below, is an brief explanation of each NEMA rating.

NEMA 1 General Purpose - Indoors Type 1 enclosures are intended for general purpose indoor use primarily to provide a degree of protection against contact with the enclosed equipment or locations where unusual service conditions do not exist.

NEMA 2 Drip Proof - Indoors Type 2 enclosures are intended for general purpose indoor use primarily to provide a degree of protection against limited amounts of falling water and dirt.

NEMA 3 Dust Tight, Rain Tight, & Ice/Sleet resistant - Indoors/Outdoors Type 3 enclosures are intended for general purpose outdoor use primarily to provide a degree of protection against windblown dust, rain, and sleet; and to be undamaged by the formation of ice on the enclosure.

NEMA 3R Rain Proof & Ice/Sleet Proof - Indoors/Outdoors Type 3R enclosures are intended for general purpose outdoor use primarily to provide a degree of protection against falling rain; and to be undamaged by the formation of ice on the enclosure.

NEMA 3S Dust Tight, Rain Tight, & Ice/Sleet Proof - Outdoors Type 3S enclosures are intended for general purpose outdoor use primarily to provide a degree of protection against sleet; and to be undamaged by the formation of ice on the enclosure.

NEMA 4 Water Tight & Dust Tight - Indoors/Outdoors Type 4 enclosures are intended for general purpose indoor or outdoor use primarily to provide a degree of protection against windblown dust and rain, splashing water, and hose directed water; and to be undamaged by the formation of ice on the enclosure.

NEMA 4x Water Tight, Dust Tight, & Corrosion Resistant - Indoors/Outdoors Type 4X enclosures are intended for general purpose indoor and outdoor use primarily to provide a degree of protection against corrosion, windblown dust and rain, splashing water, and hose-directed water; and to be undamaged by the formation of ice on the enclosure.

NEMA 5 Superseded by NEMA 12 for Control Apparatus Type 5 see NEMA 12

NEMA 6 Submersible, Water Tight, Dust Tight, & Ice/Sleet Resistant - Indoors/Outdoors Type 6 enclosures are intended for general purpose indoor or outdoor use primarily to provide a degree of protection against the entry of water during temporary submersion at a limited depth; and to be undamaged by the formation of ice on the enclosure.

NEMA 7 Underwriters Lab Class 1-Groups C&D -Explosion Proof - Indoors Type 7 enclosures are for indoor use in locations classified as Class I, Groups A, B, C, or D, as defined in the National Electrical Code. Type 7 enclosures shall be capable of withstanding the pressures resulting from an internal explosion of specified gases, and contain such an explosion sufficiently that an explosive gas-air mixture existing in the atmosphere surrounding the enclosure will not be ignited. Enclosed heat generating devices shall not cause external surfaces to reach temperatures capable of igniting explosive gas-air mixtures in the surrounding atmosphere. Enclosures shall meet explosion, hydro-static, and temperature design tests.

NEMA 8 Underwriters Lab Class 1-Groups C&D -Explosion Proof - Indoors Type 8 is same as NEMA 7, except the unit is oil-immersed

NEMA 9 Underwriters' Lab Class II - Groups E,F,G - Indoors Type 9 enclosures are intended for special purpose indoor use in locations classified as hazardous (Class II, Groups E, F, or G, as defined in the National Electrical Code). Type 9 enclosures shall be capable of preventing the entrance of dust. Enclosed heat generating devices shall not cause external surfaces to reach temperatures capable of igniting or discoloring dust on the enclosure or igniting dust-air mixtures in the surrounding atmosphere. Enclosures shall meet dust penetration and temperature design tests, and aging of gaskets (if used).

NEMA 10 Bureau of Mines

NEMA 11 Corrosion Resistant & Drip Proof - Oil Immersed - indoors

NEMA 12 Industrial Use - Dust Tight & Drip Tight - Indoors Type 12 enclosures are intended for industrial indoor use primarily to provide a degree of protection against dust, falling dirt, and dripping noncorrosive liquids.

NEMA 13 Oil Tight & Dust Tight - Indoors Type 13 enclosures are intended for industrial indoor use primarily to provide a degree of protection against dust, spraying of water, oil, and noncorrosive coolant.

Comparing NEMA and IP enclosure ratings. This comparison is only approximate, and it is the responsibility of the user to verify the enclosure rating necessary for the given application.

The below table was extract from NEMA Standards Publication 250-2003, "Enclosures for Electrical Equipment (1000 Volts Maximum)"

Enclosure

This comparison is based on tests specified in IEC Publication 60529

Also not that Table A-1 above provides an equivalent conversion from the enclosure Type numbers in this Standard to the IEC Enclosure Classification Designations. The enclosure type numbers meet or exceed the test requirements for the associated IEC Classification; for this reason Table A-1 cannot be used to convert from IEC Classifications to enclosure Type numbers.