Do not use commercial Ethernet cables, hardware in harsh environments, Belden says

Commercial-grade cabling and hardware is simply not tough enough for use in harsh industrial environments, such as discrete manufacturing and processing plants, or infrastructure facilities.

By Control Engineering Staff February 5, 2009

Engineering-driven Ethernet articles

Gigabit Ethernet: Is the Time Right?
Real-time Ethernet Applications
Don’t Rip Out Your Legacy Network

Richmond, IN – Commercial-grade cabling and hardware is simply not tough enough for use in harsh industrial environments, such as discrete manufacturing and processing plants, or infrastructure facilities, such as wastewater treatment plants and shipyards, says Patricia Saito-Carvallo, Belden’s business unit manager for industrial cable .
In these environments, networked devices and cables are routinely exposed to dust, moisture, vibration, extreme temperatures, and exposure to oil and corrosive solvents, as well as frequent movement of heavy vehicles and equipment on the plant floor, Saito-Carvallo says.

Belden 7940A Cat 6 Unshielded Twisted Pair (4-Pair UTP) 23 AWG cable has solid bare copper conductor and a heavy-duty oil- and sunlight-resistant jacket. Belden Bonded-Pair patented design (see drawing) bonds individual insulated conductors of each pair along the full length of the cable.

Using commercial Ethernet components in these environments poses a real danger of physical layer damage, which can result in incremental performance degradation, intermittent operation, and even catastrophic network failure, she says. Only ruggedly built industrial-grade cabling, switches and connectivity components can provide the protection needed to ensure that the communications infrastructure will perform reliably over time, averting the signal transmission problems that can lead to excessive downtime, costly repairs, lost productivity and reduced safety.
What industrial Ethernet users need
Industrial Ethernet users should select, according to Saito-Carvallo:
• Tough Category 5e, Enhanced Category 5e or Category 6 UTP or STP cables with heavy-duty jackets that resist moisture, oil, chemicals, and sunlight and are built to operate over a wider temperature range than commercial cables. Armored cables are also available for use in extremely harsh environments.
• IP67 and IP20 RJ45 cordsets, IP67 jacks, plug kits, surface mount boxes with stainless steel covers, and stainless steel faceplates.
• Industrial-grade switches that provide vibration and shock immunity, and offer better resistance to dust, oil and EMI/RFI interference. A variety of industrial switches provide features such as network and switch diagnostics; IP67 sealing, and millisecond network resiliency through redundant media to ensure network availability.
• Machine and factory automation components fabricated of exceptionally durable materials that can withstand harsh ambient conditions of shock, vibration, dust and frequent washdowns, and support data speeds as high as 10 Gigabits per second.
Belden develops and sells signal transmission solutions for the industrial, enterprise, building management, broadcast, and security markets.
The Belden Ethernet Cable Selection Guide (PDF) offers more information.
– Edited by Mark T. Hoske , editor in chief
Control Engineering System Integration eNewsletter
Register here .