A big buzz phrase in the antenna world is “IP rating.” But what is unclear is what antenna IP rating is needed for your application or design. You may have heard that outdoor antennas need to be “IP 67,” but is that in fact true? Here we’ll break down what IP codes really are and define the parameters surrounded with each number. The phrase IP means different things to people depending on the situation in which it is used. The most common uses cover Intellectual Property, Internet Protocol or, as we’ll discuss, Ingress Protection.
With respect to IP rating, we refer to the level of protection provided by a piece of equipment against one of two complementary standards. The first is the set of capabilities specified by the National Electrical Manufacturers Association (NEMA), and the second is specified by the International Electrotechnical Commission (IEC). This post will focus on this second set of standards, IEC 60529, also known as the IP standard.
IEC 60529 (or EN 60529 in Europe) denotes the protection provided by a product using a two-digit code following the IP rating prefix (IPxx). The first digit describes the protection against intrusion by foreign objects and dust, and the second digit specifies the protection against water. Unfortunately for manufacturers, there is not a direct correlation between the IPxx ratings and the NEMA rating values, but comparison charts which provide guidance are readily available on the web.
Table 1 lists the protection provided based on the first digit in the IPXx code. A point to appreciate is that even at a high-level of protection, such as IP5x, the ingress of material into the system is not prohibited, but the presence of the material must not compromise the operation of the system. Most industrial equipment will be protected to IP5x or IP6x level.
|Level sized||Effective against||Description|
|0||—||No protection against contact and ingress of objects|
|1||>50 mm||Any large surface of the body, such as the back of a hand, but no protection against deliberate contact with a body part|
|2||>12.5 mm||Fingers or similar objects|
|3||>2.5 mm||Tools, thick wires, etc.|
|4||>1 mm||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 air flow.|
Table 2 lists the protection provided based on the second digit of the IPxX code; protection against the ingress of water into the system. Again there are a couple of points to consider with the water rating. The first is that as with IP5x, the ingress of water is not prohibited, but the presence of the water should not interfere with the operation of the system. The second, more critical point, is that unlike the first digit rating, after IPx6 the protection against water ingress is not necessarily “better.”
|Level||Protection against||Effective against||Details|
|1||Dripping water||Dripping water (vertically falling drops) shall have no harmful effect on the specimen when mounted in an upright position onto a turntable and rotated at 1 RPM.||Test duration: 10 minutes
Water equivalent to 1 mm rainfall per minute
|2||Dripping water when tilted at 15°||Vertically dripping water shall have no harmful effect when the enclosure is tilted at an angle of 15° from its normal position. A total of four positions are tested within two axes.||Test duration: 2.5 minutes for every direction of tilt (10 minutes total)
Water equivalent to 3 mm rainfall per minute
Water falling as a spray at any angle up to 60° from the vertical shall have no harmful effect, utilizing either: a) an oscillating fixture or b) A spray nozzle with a counterbalanced shield.
Test a) is conducted for 5 minutes, then repeated with the specimen rotated horizontally by 90° for the second 5-minute test. Test b) is conducted (with shield in place) for 5 minutes minimum.
For a Spray Nozzle:
Test duration: 1 minute per square meter for at least 5 minutes
For an oscillating tube:
Test duration: 10 minutes
Water Volume: 0.07 l/min per hole
|4||Splashing of water||
Water splashing against the enclosure from any direction shall have no harmful effect, utilizing either: a) an oscillating fixture or b) A spray nozzle with no shield.
Test a) is conducted for 10 minutes. Test b) is conducted (without shield) for 5 minutes minimum.
|Oscillating tube: Test duration: 10 minutes, or spray nozzle (same as IPX3 spray nozzle with the shield removed)|
|5||Water jets||Water projected by a nozzle (6.3 mm) against enclosure from any direction shall have no harmful effects.||Test duration: 1 minute per square meter for at least 3 minutes
Water volume: 12.5 liters per minute
Pressure: 30 kPa at distance of 3 m
|6||Powerful water jets||Water projected in powerful jets (12.5 mm nozzle) against the enclosure from any direction shall have no harmful effects.||Test duration: 1 minute per square meter for at least 3 minutes
Water volume: 100 liters per minute
Pressure: 100 kPa at distance of 3 m
|6K||Powerful water jets with increased pressure||Water projected in powerful jets (6.3 mm nozzle) against the enclosure from any direction, under elevated pressure, shall have no harmful effects. Found in DIN 40050, and not IEC 60529.||Test duration: at least 3 minutes
Water volume: 75 liters per minute
Pressure: 1000 kPa at distance of 3 m
|7||Immersion, up to 1 m depth||Ingress of water in harmful quantity shall not be possible when the enclosure is immersed in water under defined conditions of pressure and time (up to 1 m of submersion).||Test duration: 30 minutes – ref IEC 60529, table 8.
Tested with the lowest point of the enclosure 1000 mm below the surface of the water, or the highest point 150 mm below the surface, whichever is deeper.
|8||Immersion, 1 m or more depth||The equipment is suitable for continuous immersion in water under conditions which shall be specified by the manufacturer. However, with certain types of equipment, it can mean that water can enter but only in such a manner that it produces no harmful effects. The test depth and/or duration is expected to be greater than the requirements for IPx7, and other environmental effects may be added, such as temperature cycling before immersion.||
Test duration: Agreement with Manufacturer
Depth specified by manufacturer, generally up to 3 m
|9K||Powerful high-temperature water jets||
Protected against close-range high pressure, high-temperature spray downs.
Smaller specimens rotate slowly on a turntable, from 4 specific angles. Larger specimens are mounted upright, no turntable required, and are tested freehand for at least 3 minutes at distance of 0.15–0.2 m.
There are specific requirements for the nozzle used for the testing.
This test is identified as IPx9 in IEC 60529.
Test duration: 30 seconds in each of 4 angles (2 minutes total)
Water volume: 14–16 liters per minute
In industrial settings, we are usually weighing tradeoffs between IPx5, IPx6 and IPx7 performance. A convenient way to consider the distinction between the three levels is IPx5 is similar to soaking the device with a nozzle from a garden hose, IPx6 is wash down from a firehose, and IPx7 is protection at the bottom of the shallow end of a pool. With this analogy, we see that an IPx7 device is not necessarily more robust than an IPx6 device. The water pressure at 1m is small compared to the force from a directed, high flow stream, with IPx6 protection, often being more difficult to practically achieve in the field.
The designer will want to carefully consider the application environment for their product and the end-customers operation and maintenance requirements. Selection of the appropriate components for the system with well-matched specifications will yield the best operational capabilities while minimizing system cost.
(Infographic from: https://www.mencom.com/news/ipingress-protection-rating-guide/)