Grounding, Part 11 - Grounding of Shielded Wire & Cable

Grounding_Series___Part_11_Grounding_of_Shielded_Wire__Cable.pdf

Transcript:

[0m:4s] Hi I'm Josh Bloom, welcome to another video in the RSP Supply education series. If you find that these videos are helpful to you. It certainly helps us out if you could give us a big thumbs up and subscribe to our channel.
[0m:15s] In today's video we will continue on in our series which we are learning about electrical grounding.
[0m:22s] In our last video, we discussed different types of grounding electrode systems and the materials used in those systems. If you have not already seen that video or the other videos in this series, we encourage you to go back and watch from the beginning so that you might better understand the concepts that are being discussed.
[0m:43s] For the purpose of this video, we want to talk about the different types of signal carrying cables and how these cables help protect sensitive information that they transmit.
[0m:56s] We also want to discuss how these cables and the shielding that is integrated into the cable need to be grounded in order for the cable to function properly.
[1m:9s] In many cases, cable or wire that need to carry signal data are more sensitive and prone to interference or disturbances. This interference can come from many different sources. Such as other electronic devices or cables that carry power. Sometimes this interference is referred to as electromagnetic interference or EMI.

[1m:33s] Radio frequencies can also have an effect and distort the data that is being transferred on these types of cables. This type of interference is referred to as radio frequency interference or RFI.

[1m:47s] There are also many other sources that can cause various levels of distortion and interference with signal carrying cables.

[1m:57s] Because of this potential distortion, it is necessary to protect the data that is being transferred in these types of cables.
[2m:5s] Many signal, carrying wires and cables offer a special shielding that is designed for this exact purpose.
[2m:13s] This shielding can help eliminate much of this EMI or RFI from corrupting the signal that is being transmitted.

[2m:22s] However, the shielding alone will not eliminate this signal distortion issue.

[2m:28s] It is imperative that this shielding be properly grounded in order to realize the full effects of the shielded cable and wire.
[2m:38s] When grounding signal carrying Shield wire, it is important to make sure a few rules are followed. First: the signal grounding should be isolated from other grounding systems that might be present in your electrical grounding system.
[2m:56s] Second:
[2m:57s] it is important that this shielding only be grounded at one point.
[3m:3s] If the Shield is grounded in more than one location, the effects of the Shield will not be realized. And in many cases can increase the potential of interference and can also cause other issues in the various electrical circuits you might be controlling.
[3m:19s] It is recommended that the Shield be terminated near the point of entrance as it enters any given structure.
[3m:26s] Also, it is imperative that this isolated grounding bar be tied to the master ground bar at one single point.
[3m:35s] This allows operators to isolate grounding issues that may occur on any signal carrying conductors.
[3m:43s] Improper grounding of these types of conductors can cause many different issues in regards to transmitting signals.
[3m:51s] If proper planning is in place and the steps we addressed in this video are followed, then most distortion and signal corruption issues can be avoided. Keep in mind that these practices are just a few methods that can be used to limit RFI and EMI for signal, carrying, cables and wires. Other methods do exist that we have not discussed in this video.
[4m:18s] For a full line of industrial grounding equipment and thousands of other products, please go to our website. For more information or other educational videos, go to
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