The Basics of NEMA and IP Ratings

Tech Tips on August 29th, 2010 Comments Off on The Basics of NEMA and IP Ratings

One of the newest members of Honeywell’s analytical product line, the APT2000 transmitter, has just received the NEMA 4X rating. Another enclosure rating which the APT2000 has received is IP65. NEMA (National Electrical Manufacturer’s Association) is an enclosure classification system which is used primarily in North America. IP (Ingress Protection) is an enclosure classification which is used primarily in Europe. Other parts of the world may use one or the other. The various definitions of the relevant NEMA and IP ratings are listed below.

NEMA Classifications pertaining to Non-Hazardous Locations

NEMA Type 1:

Type 1 enclosures are intended for indoor use primarily to provide a degree of protection against limited amounts of falling dirt.

NEMA Type 2:

Type 2 enclosures are intended for indoor use primarily to provide a degree of protection against limited amounts of falling water and dirt.

NEMA Type 3:

Type 3 enclosures are intended for outdoor use primarily to provide a degree of protection against rain, sleet, wind-blown dust, and damage from external ice formation.

NEMA Type 3R:

Type 3R enclosures are intended for outdoor use primarily to provide a degree of protection against rain, sleet and damage from external ice formation.

NEMA Type 3S:

Type 3S enclosures have the same provision as Type 3 with the addition of providing for operation of external mechanisms when ice-laden.

NEMA Type 4:

Type 4 enclosures are intended for indoor or outdoor use to provide a degree of protection against windblown dust and rain, splashing water, hose-directed water, and damage from external ice-formation.

NEMA Type 4X:

Type 4X enclosures have the same provision as Type 4 enclosures with the addition of corrosion-resistance.

NEMA Type 5:

Type 5 enclosures are intended for indoor use primarily to provide a degree of protection against settling airborne dust, falling dirt, and dripping non-corrosive liquids.

NEMA Type 6:

Type 6 enclosures are intended for indoor or outdoor use primarily to provide a degree of protection against hose-directed water, the entry of water during occasional temperorary submersion at a limited depth, and damage from external ice formation.

NEMA Type 6P:

Type 6P enclosures have the same provision as Type 6 enclosures with the addition of protection against the entry of water during prolonged submersion at limited depth.

NEMA Type 12:

Type 12 enclosures are intended for indoor use primarily to provide a degree of protection against circulating dust, falling dirt, and dripping non-corrosive liquids.

NEMA Type 12K:

Type 12K enclosures (with knockouts) are intended for indoor use primarily to provide a degree of protection against circulating dust, falling dirt, and dripping non-corrosive liquids.

NEMA Type 13:

Type 13 enclosures are intended for indoor use primarily to provide a degree of protection against dust, spraying of water, oil and non-corrosive coolant.

Ingress Protection (IP) Codes


Approximate NEMA equivalents to IP: