When water or dust enters electrical and electronic equipment, the equipment is prone to damage or failure. IEC classifies the ability of the enclosure to resist the ingress of dust or liquid. This rating is widely used throughout the industry.
IEC 60529 also assesses the ease of personal access to potentially hazardous parts within the enclosure. This standard, prepared by IEC Technical Committee 70, uses IP codes to evaluate the degree of protection provided by enclosures of electrical equipment with a rated voltage not exceeding 72.5 kV. The standard also defines the tests to be performed to verify that the enclosure meets these requirements.
The IP code consists of two numbers:
The first number is the degree of protection against solid objects, ranging from 0 (no protection) to 6 (no dust entry).
Ezitown supply metal enclosure compliant IP66 and Nema4x protection level.under testing report issued by UL.
The second number rates the liquid protection of the enclosure and uses a scale from 0 (unprotected) to 9 (high pressure hot water at different angles).
NEMA（美国国家电气制造业协会）等级和IP对应等级表
6 = 全方位防强喷水 – 进入极为有限。
| NEMA Rating | IP Equivalent | NEMA Definition | IP Against Objects | IP Against Liquids |
| 1 | IP10 | Enclosures constructed for indoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment and to provide a degree of protection against falling dirt | 1 = Protected against solid foreign objects of 5 cm (2 in) diameter and greater | 0 = Not protected |
| 2 | IP11 | Enclosures constructed for indoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, and to provide a degree of protection against dripping and light splashing of liquids | 1 = Protected against solid foreign objects of 5 cm (2 in) diameter and greater | 1 = Protected against vertically falling water drops |
| 3 | IP54 | Enclosures constructed for indoor or outdoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow and windblown dust; and that will be undamaged by external formation of ice on the enclosure | 5 = Protected against dust; limited to ingress (no harmful deposit) | 4 = Protected against water sprayed from all directions; limited to ingress permitted |
| 3R | IP14 | Enclosures constructed for indoor or outdoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet and snow; and that will be undamaged by external formation of ice on the enclosure | 1 = Protected against solid foreign objects of 5 cm (2 in) diameter and greater | 4 = Protected against water sprayed from all directions; limited to ingress permitted |
| 3S | IP54 | Enclosures constructed for indoor or outdoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow and windblown dust; and in which the external mechanism(s) remain operable when ice laden | 5 = Protected against dust; limited to ingress (no harmful deposit) | 4 = Protected against water sprayed from all directions; limited to ingress permitted |
| 4 | IP56 | Enclosures constructed for indoor or outdoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow, windblown dust, splashing water and hose-directed water; and that will be undamaged by external formation of ice on the enclosure | 5 = Protected against dust; limited to ingress (no harmful deposit) | 6 = Protected against strong jets of water from all directions; limited to ingress permitted |
| 4X | IP56 | Enclosures constructed for indoor or outdoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt, rain, sleet, snow, windblown dust, splashing water and hose-directed water, and corrosion; and that will be undamaged by external formation of ice on the enclosure | 5 = Protected against dust; limited to ingress (no harmful deposit) | 6 = Protected against strong jets of water from all directions; limited to ingress permitted |
| 5 | IP52 | Enclosures constructed for indoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against settling airborne dust, lint, fibers and flyings: and to provide a degree of protection against dripping and light splashing of liquids | 5 = Protected against dust; limited to ingress (no harmful deposit) | 2 = Protected against direct sprays of water up to 15° from the vertical |
| 6 | IP67 | Enclosures constructed for indoor or outdoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against hose-directed water and the entry of water during occasional temporary submersion at a limited depth; and that will be undamaged by external formation of ice on the enclosure | 6 = Totally protected against entry of dust | 7 = Protected against effects of submersion from 15 cm (6 in) to 1 m (3 ft) |
| 6P | IP68 | Enclosures constructed for indoor or outdoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against hose-directed water and the entry of water during occasional prolonged submersion at a limited depth; and that will be undamaged by external formation of ice on the enclosure | 6 = Totally protected against entry of dust | 8 = Protected against the effects of occasional submersion in water, up to 10 m (33 ft) |
| 12 | IP52 | Enclosures constructed (without knockouts) for indoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against circulating dust, lint, fibers and flyings: and to provide a degree of protection to against dripping and light splashing of liquids | 5 = Protected against dust; limited to ingress (no harmful deposit) | 2 = Protected against direct sprays of water up to 15° from the vertical |
| 12K | IP52 | Enclosures constructed with knockout(s) for indoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against circulating dust, lint, fibers and flyings: and to provide a degree of protection to against dripping and light splashing of liquids | 5 = Protected against dust; limited to ingress (no harmful deposit) | 2 = Protected against direct sprays of water up to 15° from the vertical |
| 13 | IP54 | Enclosures constructed for indoor use; to provide a degree of protection to personnel against incidental contact with the enclosed equipment; to provide a degree of protection against falling dirt; against circulating dust, lint, fibers and flyings: and against the spraying, splashing and seepage of water, oil and non-corrosive coolants. | 5 = Protected against dust; limited to ingress (no harmful deposit) | 4 = Protected against water sprayed from all directions; limited to ingress permitted |
