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Superseded by NEMA 12 for Control Apparatus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.