• Water and dust protection
• Vibration and shock resistance
• Operating in extreme conditions

Industrial-grade networking devices typically feature operating temperatures between 0° and 60°C (32° and 140°F), a rugged metal housing, and 6 to 8 KV ESD protection. Although these specifications provide excellent reliability for many industrial applications and environments, there are situations where a much tougher standard is required. How can a system integrator know if a networking device is tough enough for a particularly demanding application? Read on to find out what you should look for.

Water and dust protection

For many heavy-duty applications, especially in outdoor environments, dirt and moisture can cause serious damage to inadequately protected equipment. Networking devices will need extra protection. You can examine the device housing for sealing effectiveness. Well-protected devices are likely to be sealed in single-piece or seamless casing and will favor membrane buttons over mechanical push-buttons. Vents or other openings will be avoided or minimized.

Since water and dust protection are critical features for many applications, the industry recognizes a standardized rating system for the level of protection offered by a device. The Ingress Protection (IP) rating, also known as the International Protection rating, indicates how well a device is protected from water and foreign objects using two digits as follows:

For standard industrial-grade devices, the minimum recommended rating is IP30, which would mean protection against items over 2.5 mm in diameter. For the most demanding industrial applications, an IP68 rating maximum protection against dust and water. Note that there is no formal process or governing body for obtaining an IP rating. Each manufacturer determines and provides its own IP ratings as desired. For users that want the most accurate and unbiased information, some manufacturers will hire independent labs to test and verify a device's IP rating.

While an IP68 rating ensure extra toughness for harsh environments, it is not sufficient for certain, specialized applications. For example, true underwater applications require additional ratings for depth or duration of submersion. IP68 does not indicate that the device can actually operate underwater, only that the device will be unharmed and will operate when removed from the water. Certain environments also pose specific hazards that the IP68 rating does not address, such as the corrosive seawater found in marine applications, or the high-temperature, high-pressure sprays found in car washes and food and beverage applications. For such applications, specialized or industry-specific ratings and certifications may be necessary, such as the IP69K rating or DNV type approval. it is not sufficient for certain, specialized applications. For example, true underwater applications require additional ratings for depth or duration of submersion. (IP68 does not indicate that the device can actually operate underwater, only that the device will be unharmed and will operate when removed from the water) Certain environments also pose specific hazards that the IP68 rating does not address, such as the corrosive seawater found in marine applications, or the high-temperature, high-pressure sprays found in car washes and food and beverage applications. For such applications, specialized or industry-specific ratings and certifications may be necessary, such as the IP69K rating or DNV type approval.

In North America, the NEMA standards are also a common way to indicate a device's toughness against water and dirt. They roughly correspond to IP ratings as follows:

Note that the higher NEMA numbers do not necessarily correspond to stronger protection.

Vibration and shock resistance

A key indicator of how tough a device is how well it stands up to vibration and shock. Electric components and connections can be very delicate. For example, very few laptops would be able to survive fall from 10 meters. However, your networking device may be installed in an environment where impacts of such severity are commonplace.

Manufacturers rely on several methods to protect their devices from both sharp impacts and repetitive motion. Obviously, the casing must be tough enough to withstand the impact. The inner components must also be securely mounted within the casing. An effective approach is to fill the device with foam or padding material that will cushion the inner components. The filler material fixes the inner components in place, so they are not disturbed even in the presence of sudden, severe motion. This adds to the cost and weight of the device, but is very effective in ensuring reliable operation through shock and vibration.

Another important item to look for is the quality of physical connections to the device. If these connections come loose, data loss and errors can bring the network systems down, even if the networking device itself remains intact. Unfortunately, the standard RJ45 connectors on typical networking devices are simply not designed for heavy-vibration environments. This has been addressed by some manufacturers by sealing the connector within a locking enclosure. Coaxial connectors have also been adapted for industrial use. Currently, most manufacturers agree that when it is possible, the most effective approach is to replace RJ45 connectors with M12 connectors. M12 connectors are specifically designed for the rigors of industrial environments and take up less space than hardened RJ45 connectors For manufacturers, this means that M12 connectors can be fitted onto a device's existing housing rather than redesigning the device from scratch. M12 connectors also provide the advantages of IP67 ratings, so connections are well protected from exposure to water or dust. However, integrators need to select the appropriate cables and devices when deciding to switch to M12 connectors.

Specifications exist to indicate a device's shock and vibration resistance. Manufacturers often indicate that their device is shock resistant to a certain number of "g's" (g-load or g-force), and vibration resistant to a certain frequency and range of oscillations such as 5 to 500 Hz. However, there are many variables and conditions involved in such measurements, and there can be a wide range in the conventions used for methodology and terminology. For users, it is simpler to rely on an internationally recognized set of certifications, such as the IEC60068-2 certifications for shock, freefall, and vibration.

Operating in extreme conditions

Many sites or environments are characterized by harsh conditions of a specific nature. For example, a device used at sea may face corrosive seawater, high water pressure, or even biological-based hazards. On the other hand, a device used for mining or gas applications may have to deal with the presence of highly flammable or explosive gases. Often, it is simply not feasible for manufacturers to address every possible extreme for every single device. Instead, specialized devices may be offered that are tailored to specific applications or environments. Manufacturers may also custom-design a product to meet a customer's exact needs.

A device's ability to handle extreme temperatures and electrical activity can be seen in its specifications. Outdoor applications, especially in certain parts of the world, can involve extreme temperatures that change quickly. In such situations, look for devices that offer a wide operating temperature range. An operating temperature range from -40° to 75°C (-40° to 185°F) ensures that the device can be installed in outdoor environments anywhere in the civilized world. When stray electricity from other devices is a serious hazard, look for at least 15 KV ESD protection.

Many hazards are highly specific to the application and environment. For almost every specialized industry, there is a set of certifications that can or must be used to qualify a device for the task. In many cases, certification is required by government policy. It is critical that you understand the regulations in effect in your region.

Since the certification process requires time and expense, manufacturers may not certify their devices for more specialized applications unless a customer requests it. If a desired certification is not listed, you can always contact the manufacturer to see if that certification can be obtained. The manufacturer may be willing to get their product certified or provide a custom version of their product to suit your purposes.

Certifications exist in thousands of variants for specific device types, applications, and regions. In addition, requirements change and are updated, and new versions are created as industries evolve. Be sure to check the certification requirements for your region and your project. Some certifications and organizations for specific environments and applications are listed below:

Conclusion

There are many considerations when trying to determine if your networking device is tough enough for your application. You can tell a lot from certain basic specifications and physical characteristics, such as operating temperature, casing material, and the presence of filler material. Beyond that you can rely on internationally recognized standards, such as IP ratings, M12 connectors, and UL certifications. Certain manufacturers can also build products to your required specifications or apply for special certifications as necessary.

Learn more about the following:

• IP67-rated Ethernet switches
• IP67 and IP68-rated wireless access points
• DNV-certified device networking products for maritime applications

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