A Standards-Based Approach to the Industrial Physical Network: Q&A Session

Webcast Q&A session with presenters Mike Berg, Solutions Marketing Manager, Panduit; and Robert Elliot, Sr. Product Development Manager, Panduit

  1. Q: Are the structured cabling and point to point cabling solutions you describe suitable for supporting Power over Ethernet?
    • A: The cabling solutions use the same types of four pair twisted pair copper cable, and will meet (depending on application) Category 5e, 6 or similar performance as defined in the TIA-568.C series of standards. As such, these cables are suitable for supporting Power over Ethernet (PoE) to both IEEE 802.3af (~ 13 watts to the device) and 802.3at (~ 25 watts to the device).

  2. Q: Can you clarify what you mean by the term ‘future proof’?
    • A: Future proof basically means that cabling infrastructure is designed and deployed with a view to ensuring that it will support growing data demands at the end of its expected life, rather just supporting data needs at the start of its life. Examples of this include installing more horizontal cables than are immediately required, simply not using the spare cables until they're needed at some future time, and / or installing horizontal cable that is capable of supporting higher data rates than currently used. An example of this might be to consider deploying Category 6A cabling capable of supporting 10 Gigabit/second, rather than Category 6 which will support 1 Gigabit/second.

  3. Q: Can you explain what is meant by the term IP20 or IP67 related to connectors used in Ethernet applications?
    • A: The letters IP stand for ingress protection and the numbers indicate the level to which the connector is protected. The first number refers to particulate matter, and the second number refers to water. A typical RJ45 patch cord connected to a work area outlet in the enterprise or office area would be rated to IP20, since little protection is given to ingress of dust, for example, and no protection is given to ingress of water. An IP67 rated connection, however, would be dust proof and water proof to a defined degree.

  4. Q: Historically, most installations have occurred very haphazardly. What is the best method to get to a standard network configuration short of a full network audit (very expensive).
    • A: Using the logical topology shown as the basis for the network diagram that shows broad location of active equipment, identifies zones and shows network connections, the TIA 1005A standard should be used to assist mapping this to the physical layer. The site of the planned installation should be reviewed to clearly identify areas that will be supporting riser cabling, horizontal cabling, where telecommunications rooms or closets and zone enclosures (consolidation points) should be located. A zone cabling architecture should be considered to help consolidate pathways.

  5. Q: How can I determine if a network is good or bad regarding performance? For example I see in most of computer networks resource <1% in an 10 MB network, If I see >6% is that good? There are a lot of Control logix plcs with the multicast.
    • A: In terms of the performance of the active equipment used, we would recommend contacting the system designer or manufacturer of the equipment. However, it is critical to ensure that the performance of the physical layer network is meeting required performance levels, to ensure that the active equipment will operate optimally. The performance that would be measured on the physical network would include parameters such as return Loss, NEXT (Near-End Cross-talk) and other parameters.

  6. Q: Is structured cable always (usually) solid copper terminated in jacks? And is P2P cable always stranded copper with preterminated (factory terminated) plugs?
    • A: Structured cabling most usually uses solid horizontal copper cabling terminated in jacks, though there are some exceptions. Some of the premise standards (TIA-862 for building automation, in particular) permit the use of a plug termination onto horizontal cable. An example of this might be a situation where a wireless access point (WAP) is deployed. The WAP has an RJ45 jack, meaning that if a horizontal cable terminated with a jack was used then a patch cord would be required and some means to support the horizontal cable jack. In space limited areas, for example above a ceiling, it is much more convenient to simply terminate the WAP end of the horizontal cable with a plug.

  7. Q: What are Panduit recommendations for grounding shielded cables when used in high EMI environments?
    • A: This is a great question. The reason is that it implicitly recognizes that when the deployment is made in a high EMI environment that shielded cabling (STP) should be used, rather than unshielded twisted pair cabling (UTP). Moving to the question, the recommendation is that if the devices that are connected through the shielded cable have a ground potential difference of greater than 1 volt, or the difference is not known or is uncertain, then the ground of the shielded cable should not be connected to the device farthest from the network switch. Otherwise, ground at both ends.

  8. Q: Why the connection between equipment need the use of patch panels, why can't we terminate the run of cable in a plug and connected directly to the equipment?
    • A: Strictly, either could be used. The point about the patch cord is that it will come from the manufacturer in a defined length. For example, say a 20 ft long patch cord was being considered. If a connection was being made from an enclosure to a control panel and the total path length was 14 ft, then the extra 6 ft of patch cord length has to be stored somewhere. Sometimes, for example in an overhead pathway, this can be easily accommodated. Other times, for example, the extra length is coiled up and placed at the bottom of and inside an enclosure or control panel. This both takes up space, may degrade performance and if there are a number of cables coiled like this can really give rise to a poor installation that is very difficult to subsequently work on. Using the field installed assembly, the cable length can more readily be cut to suit. Additionally, because of the RJ45 or M12 connector, a patch cord is limited in that it can't readily be pulled through conduit.

  9. Q: Why wouldn’t I just use a patch cord instead of a field assembled point to point link?
    • A: Strictly, either could be used. The point about the patch cord is that it will come from the manufacturer in a defined length. For example, say a 20 ft long patch cord was being considered. If a connection was being made from an enclosure to a control panel and the total path length was 14 ft, then the extra 6 ft of patch cord length has to be stored somewhere. Sometimes, for example in an overhead pathway, this can be easily accommodated. Other times, for example, the extra length is coiled up and placed at the bottom of and inside an enclosure or control panel. This both takes up space, may degrade performance and if there are a number of cables coiled like this can really give rise to a poor installation that is very difficult to subsequently work on. Using the field installed assembly; the cable length can more readily be cut to suit. Additionally, because of the RJ45 or M12 connector, a patch cord is limited in that it can't readily be pulled through conduit.