The proliferation of digital information, wireless handheld devices, and Ethernet into every facet of our lives means that connections to networks need to be in more places than ever before. There are an increasing number of everyday environments not quite severe enough to be considered “industrial,” but still in need of something more ruggedized than what exists in everyday commercial office environments.
Cabling for Harsh Environments
Manufacturing environments have rapidly migrated to Industrial Ethernet over the past decade as a means to deliver information for industrial automation and control systems and to integrate factory environments with the corporate LAN. Because of this, the industry is seeing a growing demand for network cables, patch cords, and connectors capable of withstanding more severe conditions.
The proliferation of digital information, wireless handheld devices, and Ethernet into every facet of our lives means that connections to networks need to be in more places than ever before. There are an increasing number of everyday environments not quite severe enough to be considered “industrial,” but still in need of something more ruggedized than what exists in everyday commercial office environments. Extending networks into these harsher environments is becoming a common requirement among network designers and installers.
As our world becomes more digital, non-industrial harsh environments that require network access are popping up everywhere – from outdoor eateries and theme parks to laboratories and warehouses. Many of these harsher environments may be subjected to dust, moisture, temperature extremes, contaminants, and other factors that can adversely impact standard commercial-grade networking components. It’s important for designers and installers faced with extending networks into these harsh environments to understand which industry standards to follow and which type of cable and connectivity to deploy, so they don’t need to replace components due to corrosion and damage from harsher environmental elements.
While standards for industrial environments are certainly applicable to factory floors, manufacturing plants, and processing facilities, the same standards can be used to determine the type of ruggedized cable and connectivity required for those in-between environments that are not as clearly identified as either commercial or industrial.
The international standard ISO/IEC 24702 provides application-independent requirements for both balanced copper and fiber optic cable systems that support Ethernet-based data communications in industrial environments. The standard provides implementation options and requirements for cable and connectivity that reflect the operating environments within industrial premises. ISO/IEC 24702, along with its comparable US TIA-1005 and European EN 50173-3 standards, incorporate the MICE method of classifying parameters for the materials needed to build an industrial network.
MICE stands for “mechanical, ingress, climatic, and electromagnetic” and includes three levels of environmental harshness: Level 1 for everyday commercial office environments, level 2 for light industrial, and level 3 for industrial.
While the MICE method is used to determine the harshness level of commercial, light industrial, and industrial, rarely is an environment exclusive to one MICE classification. Furthermore, one run of cabling from point A to point B can traverse through various MICE classifications along the route. Designers planning cabling systems in harsh environments need to have a good understanding of the environment and what constitutes levels 1, 2, and 3 for each parameter. In some cases, measuring the environment can require specialized equipment, especially when it comes to measuring vibration and electromagnetic interference. The standards include MICE tables to help determine which levels exist within the targeted environment.
The trick to using MICE levels to determine components is to always consider the worst-case scenario and worst-case level parameter, regardless of the other parameters. For example, an environment exposed to liquid may be classified as M1I3C1E1. If only ruggedized components meeting M3I3C3E3 are available, they may need to be used regardless of whether that level of protection is required for all parameters.
When it comes to selecting ruggedized cable and connectivity, both copper and fiber solutions may need to be considered – especially as more fiber is extending out of the commercial data center and telecommunications room environment to bring higher bandwidth closer to the work area outlet or to deal with longer-distance requirements.
While not all MICE parameters will relate to both copper and fiber, especially with fiber being immune to electromagnetic interference, the IP66/IP67 rating on connectivity can easily apply to both, as can other mechanical, climatic, and chemical parameters. In general, ruggedized cable and connectivity solutions for harsher environments should feature components and characteristics such as the following:
- Chemical-resistant thermoplastic housing on connectivity – Plugs and outlets should use materials that provide the widest range of protection from most solvents and common industrial chemicals.
- Dust caps for outlets – Ruggedized dust caps can protect unused outlets and seal outlets during washdowns.
- IP67-rated copper and fiber connectivity – Ruggedized outlets and modular patch cords with an IP66/IP67-rated seal protect plugs and outlet contacts from dust and moisture.
- Shielded twisted-pair cabling for copper – Shielded copper cabling such as F/UTP cables and S/FTP cables will provide much higher resistance to EMI/RFI.
- More durable cable jacket materials – Jacket materials such as polyurethane and thermoplastic elastomers can provide better tensile strength and lower temperature flexibility and brittle points, as well as better tear, abrasion, chemical, and moisture resistance.
- IP44-rated faceplates – Stainless steel faceplates with rear sealing gaskets provide a protective seal from moisture and debris.
- NEMA 4X enclosures – Enclosures and surface-mount boxes with a NEMA rating will protect the termination points of ruggedized outlets.
With an increase in the number of harsh environments that are an extension of the corporate LAN, designers and installers who are experienced in commercial environments may not necessarily understand industrial standards, how to use MICE parameters, or which product features to look for. Furthermore, standards-based methods and parameters for determining the level of harshness and the components required are not always cut and dry.
While industry standards can be used for determining components based on environment, they often refer to in-between environments as “light industrial.” This term can be confusing when the environment is clearly not one that is industrial but is simply an extension of the commercial LAN into a harsher environment. Consequently, “industrial” standards are not always followed during the planning stages of these environments, which can result in the use of inadequate components and network failures.
This article was contributed by Siemon, and will appear in ConnectorSupplier.com’s upcoming eBook, The Industrial Connector Handbook.