Weather rating
Electrial equipment that comes in an enclosure will and enclosures intended for electrical equipment of any kind will be rated based upon the protection that the enclosure can provide against accidental contact and damage from the entrance of water or objects. It is important to check the rating any enclosure being considered to make sure that it is suitable for the location in which the equipment will be installed. There are two different rating systems that are commonly used globally: National Electrical Manufacturers Association (NEMA) rating and Ingress Protection (IP) rating. The two systems are very similar, but it is not possible to create a direct equivalency between the two.
Ingress protection
A set of standards created by the International Electrotechnical Commission (IEC). Sometimes also referred to as the Ingress Protection Code (IPC). The code may contain other letters and numbers beyond the first two, but these are not relevant for offgrid PV system design and installation. The first character after IP signifies the protection that the enclosure provides against the entrance of foregin bodies and protection of people from hazardous parts. The second character after IP signifies the protection that the enclosure provides against the entrance of moisture.
Example 1: An enclosure is rated IP 65. What level of protection does it offer?
- 6 signifies that it is rated as dust-tight.
- 5 signifies that it is protected against water projected from a nozzle.
| Code letters | First characteristic numeral: Solid particle protection | Second digit: Liquid ingress protection |
|---|---|---|
| IP (Ingress Protection) | Single numeral: 0–6 or letter X | Single numeral: 0–8 or letter X |
| Mandatory | Mandatory | Mandatory |
Solid particle protection
The first digit indicates the degree of protection (of people) from hazardous parts, as well as the protection of enclosed equipment from foreign bodies.[1][2]
| Level sized | Effective against | Description |
|---|---|---|
| X | — | X means there is no data available to specify a protection rating with regard to this criterion. |
| 0 | — | No protection against contact and ingress of objects |
| 1 | 50mm | Any large surface of the body, such as the back of a hand, but no protection against deliberate contact with a body part |
| 2 | 12.5mm | Fingers or similar objects |
| 3 | 2.5mm | Tools, thick wires, etc. |
| 4 | 1mm | Most wires, slender screws, large ants etc. |
| 5 | Dust protected | Ingress of dust is not entirely prevented, but it must not enter in sufficient quantity to interfere with the satisfactory operation of the equipment. |
| 6 | Dust-tight | No ingress of dust; complete protection against contact (dust-tight). A vacuum must be applied. Test duration of up to 8 hours based on airflow. |
Liquid ingress protection
The second defines the protection level that the enclosure enjoys from various forms of moisture (drips, sprays, submersion etc).[1][2]
| Level | Protection against |
|---|---|
| X | X means there is no data available to specify a protection rating with regard to these criteria. |
| 0 | No protection against ingress of water |
| 1 | Dripping water |
| 2 | Dripping water when tilted at 15° |
| 3 | Spraying water |
| 4 | Splashing of water |
| 5 | Water jets |
| 6 | Powerful water jets |
| 6K | Powerful water jets with increased pressure |
| 7 | Immersion, up to 1m depth |
| 8 | Immersion, 1m or more depth |
| 9K | Powerful high-temperature water jets |
Notes
- ↑ 1.0 1.1 Enclosure Company: IP Ratings Explained https://www.enclosurecompany.com/ip-ratings-explained.php
- ↑ 2.0 2.1 Source IEX: Degrees of Protection http://www.sourceiex.com/Catalogs/IP%20Degress%20Testing%20Details.pdf
