Spend any time looking at electrical and electronics enclosures, and you’ll likely come across the phrase “ingress protection.” What’s more, you’ll gather that ingress protection is a pretty important feature for a device enclosure.
But what exactly is ingress protection, and why do device designers and manufacturers consider it so important? How can your business decide what kind of ingress protection is right for its products and its tools? In this article, we’ll examine these important questions about ingress protection and how they can help determine which enclosure is right for your application.
According to Merriam-Webster, “ingress” means “the power or liberty of entrance or access.” Thus, ingress protection prevents something from entering a space. An enclosure with ingress protection is designed to prevent entry by solids, liquids or both.
Many people use ingress protection techniques frequently in their day-to-day lives. Placing a sandwich in a sealed plastic container is a form of ingress protection that keeps dirt and dust from getting on your food. Adding a waterproof case to your smartphone is another form of ingress protection that prevents liquids from damaging your phone.
Electrical and electronic devices are often highly sensitive to particulate matter (such as dust, dirt or metal shavings) and/or liquids (such as water, coolant or oil). Ingress from these environmental hazards can cause serious damage to costly devices and can even create safety hazards in the event of critical device failures. A good device enclosure protects its contents against these potentially damaging environmental hazards by preventing their ingress.
Several different design features can help prevent ingress. The enclosure may be manufactured so that its seams and gaps are extremely tight and don’t allow ingress from liquids or dust. This is easiest for enclosures that are screwed closed rather than enclosures that have hinged doors. However, even the most precise manufacturing techniques often leave a tiny amount of space that can be vulnerable to environmental hazards, so a sealing technique such as gasketing may be required.
Gasketing is another method used to achieve ingress protection in enclosures. A gasket is a molded rubber or plastic piece that seals a space against ingress by liquids and/or dust. Gaskets come in many forms, including strip gaskets, die-cut gaskets, form-in-place gaskets and bulb extrusion gaskets. Each has different advantages and is suited to different devices and enclosure designs. You’ll often find gaskets on enclosures with hinged panels that swing open or otherwise need to be opened and resealed.
In specialty cases where an enclosure’s contents will not need future modification, the enclosure is sometimes filled with silicone gel after the components are assembled. This technique provides excellent resistance to environmental hazards, but it has the built-in downside of preventing further modification of the enclosure’s contents.
Device designers use two systems of ingress protection ratings to identify and rate an enclosure’s ingress protection characteristics. Each of the two systems rates particular qualities of an enclosure’s ingress protection.
One of these systems is called the Ingress Protection (IP) rating system. IP ratings are two-digit numbers, with the first number representing the enclosure’s solid ingress protection and the second number representing its liquid ingress protection. IP rated enclosures can offer great protection for your device, but you’ll need to understand how the ratings work in practice first.
As an example, let’s break down the rating of an IP68 electrical box. According to the IP rating system, the first digit–6–tells us that this is a completely dust-tight enclosure, totally protected from ingress by dust and dirt. The second number–8–tells us that it is also a completely watertight enclosure, even when submerged for a prolonged period of time.
Thus, a designer or engineer who sees that an enclosure carries an IP68 rating can be confident that it provides effective protection against the harshest environmental conditions. If the designer doesn’t need that level of protection, she may be able to save money by selecting an enclosure with an IP66 rating or IP67 rating instead.
The other system is called the NEMA (National Electrical Manufacturers Association) rating system. NEMA ratings use a combination of letters and numbers to rate several characteristics of an enclosure, including its ingress protection. For more information on NEMA ratings, see our NEMA ratings guide, our NEMA to IP conversion guide and our comparisons of common NEMA ratings and IP ratings such as NEMA 4 vs. IP65.
Polycase YH-080604 NEMA 6 Hinged Electrical Enclosure
Understanding the basics of ingress protection will set you up for success in protecting your devices from environmental hazards. For more information on the ingress protection characteristics of Polycase’s many IP-rated enclosures, just call us at 1-800-248-1233 or contact our enclosure experts online.