Traditionally, industrial networks have been set up in a point-to-point
(pictured right) configuration, with a single cable terminated to plugs (i.e.,
a long patch cord).
Structured cabling is emerging as a more robust and sustainable
infrastructure because it better facilitates growth and troubleshooting,
factors that are important to manufacturing. However, there are pros and cons
to each approach, depending on the implementation.
Point-to-point is ideal for short cable runs in an enclosure or small
ring applications. However, plugs can be hard to terminate. Another
consideration is stranded vs. solid cables. Stranded cables lead to reduced
distance because of higher attenuation, while a solid conductor cable can break
due to flexing. More importantly, fixed length, point-to-point cables cannot be
readily extended or reconfigured as a structured approach with patch panels. In
addition, some network test equipment excludes connections to the tester,
therefore the entire channel is not tested.
Structured cabling (pictured left) is the preferred implementation for longer and more critical runs, such as connecting enclosures, machines, test equipment, and cameras, as it provides a means for troubleshooting and testability, growth, and reliability. Utilising patch cords, jacks, and horizontal cabling creates an optimized network channel. Also, the horizontal cable is easier and faster to reliably terminate to a jack versus a plug.
By installing network cabling to create spare network channels for growth, technicians can connect to a different channel when adding equipment or in the event of a network cabling failure.
While there is a focus on channel resiliency, the value of structured cabling is its systematic approach to planning and deploying cabling and cable management based on the Telecommunications Infrastructure Standard for Industrial Premises (TIA-1005-A).
Media Selection
Cable media is influenced by cable reach, harsh environments, electrical noise, bandwidth, and switch convergence. For example, proper copper channel cable transmits 100m while single-mode fibre optic cable can reach distances of many kilometres, depending on the transceiver selection
- Corrosive, wet, and oily environments all impact network cable jackets, causing degradation. There are a variety of outer jacket coverings such as polyurethane, polyvinyl chloride (PVC), and thermoplastic elastomer (TPE), which have varying levels of cable protection. The toughest jacket covering, polyurethane, is abrasion- and tear-resistant, and resistant to oil, radiation, fungus, oxidation, and ozone. Beneath the outer jacket, metallic foil or braid may be used to suppress electrical noise.
- Bandwidth requirements may necessitate higher category copper such as Category 6 and perhaps multi-mode and single-mode fibre that can transmit up to 10Gb/s.
- Deploying fibre cable for interswitch links in rings or redundant star configurations can minimise the recovery time from network interruption.
- In less complex, smaller networks, copper may be suitable, but the recovery time for network faults needs to be weighed against downtime costs.
