For people, inhospitable environments, such as extreme heat or cold, cause considerable bodily harm over time. This is also true for electronics. An electrical current can be damaged or destroyed by harsh environments causing connectivity issues.
The standard workbench is usually a dry, static-free, radiation-proof habitat. But in the outside world, conditions are not so temperate. Investing in systems designed to stand up to harsh environments is vital to today’s ultra-connected society.
In this article, we look at the conditions under which environments are classified as “harsh” and provide some examples of the certification types required.
Types of Harsh Environments
Determining the specific environment in which a product is used should always be one of the first considerations. No matter the industry, should a switch, connector, or cabling system break down, the cost of replacement parts or repair and production downtime can be ruinous. That makes an investment in an industrial-grade Ethernet infrastructure a wise approach. Even the highest-quality commercial off-the-shelf (COTS) Ethernet systems are not designed to handle these harsh conditions over time.
Extreme Temperature Environments
Ice and snow can cause COTS cables to become stiff and brittle. Simultaneously, too high temperatures can degrade the plastic used in cable construction and reduce the amplitude of a signal or electric current (this is called attenuation). While COTS cables can operate at temperatures from -20०C to +60०C, an industrial-grade cable can withstand temperatures from -40०C to +85०C.
In industrial settings, vibration and impactions are at issue. Vibrations can devastate electronics and mechanical parts as solder connections can snap, and mechanical fittings can “undo” themselves. Electronics are not just in danger at solder connections, even integrated circuits—especially micro-electromechanical systems (MEMs)—can be damaged under vibration and impact stress. Electrical performance can also be negatively impacted by electromagnetic interference (EMI) or radio-frequency interference (RFI).
Chemical environments can be extremely caustic. For example, ferric chloride is used in many applications: sewage and industrial waste treatment, water purification, as an etching agent for circuit board engraving, as well as in the manufacturing of other chemicals. Any steel tools or mechanisms that come in contact with ferric chloride or its fumes will quickly rust and begin to dissolve. Any number of chemicals, oils, solvents, and cleaning solutions can, especially with heat, soak into COTS cables, causing the cable jackets to swell and lose strength.
Electrical environments can be harsh. Think about things like MRI machines that can stress the medical equipment surrounding them—OR—power station circuitry affected by large transformers. Think EMI and electrostatic discharge (ESD). Something as familiar as air purification used to remove dust particles can be a stressor on electrical equipment.
Environments with UV Radiation Exposure
Excessive exposure to sunlight can accelerate the decomposition rate of COTS cable jackets. Cosmic particles, such as ions and radiation, pierce the Earth’s atmosphere all the time. Computers are particularly vulnerable as charge cosmic particles often cause bits to flip (e.g., a bit stored in RAM) and latches to lock (e.g., inability to change state).
Ion radiation is of particular concern in aerospace applications where circuits are heavily exposed. These applications require robust shield technology and circuitry protections.
The bottom line is: only hardened industrial-grade components are up to the task of withstanding the environmental challenges discussed above.
Now, let’s look at some of the types of certifications available to help choose the proper equipment to operate in a harsh environment.
Harsh Environment Certifications
Several product certifications help end-users choose the correct grade of equipment to operate in harsh environments. Here are a few:
The International Electrotechnical Commission (IEC) has devised a safety rating system called the Ingress Protection (IP) Rating. Ingress refers to the level at which component is resistant to permeation from a solid (e.g., dust) or liquid (e.g., water).
Electrical enclosures receive an IP rating that consists of two numbers; the first number rates solids while the second number rates liquids. Each number can be decoded by referring to the IP Rating Chart. For example, switches that are IP65-rated are protected from total dust ingress (as noted by the number “6”), while the number “7” indicates the switch is protected if immersed in liquid between 15cm and 1m of depth. To learn more, visit here.
The National Electrical Manufacturers Association (NEMA) provides a standard for protective enclosures similar to the IP code (IEC 60529). NEMA 250 covers a wider set of harsh conditions than the IP code. This standard includes ratings for indoor and outdoor environments—both hazardous and nonhazardous. NEMA ratings cover the ingress of foreign objects (solids), water, corrosive agents, and a variety of gases and atmospheres. NEMA ratings can be compared to IP ratings with the use of a NEMA/IP Equivalency Chart.
Underwriters Laboratories LP Certification
Underwriters Laboratories (UL) launched a study to address heat-related issues with the transmission of limited power over communications cable. As a result, UL developed a Limited Power (LP) Certification that provides a simple way to ensure that installations are not vulnerable to excessive heat issues. Certified cables carry the UL Mark to ensure a reduced risk and compliance.
National Electric Code
As of 2017, the National Electric Code (NEC) imposed new requirements on cables running the high-powered, next-generation Power over Ethernet standard (PoE+). These requirements focus on the overall bundle sizes of cables running on PoE+ power levels and apply only to permanently-installed cables. The NEC recognizes the UL LP listing.
Other Standards Organizations
For further information, here is a relatively comprehensive list of other standards organizations:
- ANSI: American National Standards Institute
- API: American Petroleum Institute
- BASEEFA: British Approval Service for Electrical Equipment in Flammable Atmospheres
- CE: Compliance to European Standards
- CSA: Canadian Standards Association
- IEC: International Electro-Technical Commission
- IEEE: Institute of Electrical and Electronics Engineers
- ISO: International Standards Organization
- MIL: Military Specifications
- NAFTA: North American Free Trade Agreement
- NEC: National Electric Code
- NEMA: National Electrical Manufacturers Association
- UL: Underwriter’s Laboratories
- UR: Underwriter’s Laboratories Recognized
A Last Word
Our world becomes more connected every day, and connectivity is vital to all facets of our lives. While not severe enough to be considered industrial, many everyday environments still need more ruggedness than ever before. Be assured that PLANET has developed a multitude of products that fit most any environmental requirements.
Contact us to learn more about PLANET’s family of industrial-grade products.