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Old 01-26-2018, 05:44 PM   #1
theKbStockpiler
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Testing RJ45 cables no ground


I'm trying to test a RJ45 cable and the tester does not light up the ground light. Is this ever normal or are all eithernet cables grounded not matter shielded or not?

Thank you for your expertise!
 
Old 01-26-2018, 06:40 PM   #2
ferrari
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No, I assume this is referring to the shield grounding which may or may not be present in a given cable. When it is present (STP cable), I'd also expect to see shielded terminations as well, designed to make contact with the socket.

Last edited by ferrari; 01-26-2018 at 06:42 PM.
 
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Old 01-26-2018, 06:54 PM   #3
astrogeek
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Disclaimer: I know nothing about your tester and test setup, and am assuming that you are referring to shield ground...

In general, shielding on cables should only be grounded at one end. I suspect that rule may not be followed by all cable manufacturers or the local cable guy who made the cable, but is still the best practice.

If your tester is looking for continuity through the shield from one end to the other then it may or may not not find that, depending on cable source.
 
Old 01-26-2018, 06:55 PM   #4
theKbStockpiler
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This is a stupid question but does the plug have to be metal to be grounded or is the ground the actual wire?
 
Old 01-26-2018, 07:13 PM   #5
astrogeek
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There is no end-to-end ground wire in the cable. The signals are all over twisted pairs, the signal being differential voltage between members of a pair, not relative to local ground.

The shield ground requires a metal cover on the cable and on the connector.

Just wondering, does your tester have any documentation which would tell you what the ground indicator indicates? I wonder if it is intended to test for leakage current between any wire and the grounded shield - that is, a grounded signal wire?

Last edited by astrogeek; 01-26-2018 at 08:14 PM. Reason: Verified, disclaimer removed
 
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Old 01-26-2018, 10:27 PM   #6
jefro
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True we don't know your tester.

I was in a transmitter area that needed to be all grounded. While most folks may not purchase cat cable with a shield or even use it there is an advantage to it. The specifications for speeds on cables assume many design and installation tolerances.

Last edited by jefro; 01-26-2018 at 10:29 PM.
 
Old 01-27-2018, 09:31 AM   #7
theKbStockpiler
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I'm using this tester.


Seems to be a good product and the initial build quality is sturdy.
The tester does have a contact point on the side of where the RJ45 plugs in. It looks like the G on the tester really should be labelled S for shield. If I test cables with metal plugs the g lights up.

I went will all cat6 shielded cables and it's a pain because cat5 is dominant in the market. There are a lot less connectors and boots available for them. Cat6 shielded is supposed to be as good as you need from what I could find in guides.

Thank you for all the replies!
 
  


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