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I was wondering, when an S/FTP cable has some outer noise and there is electricity induced in its shielding, where does it go? I have a keystone wall outlet which is metal (with plastic cover), and the keystone modules are metal as well. Does the electricity flow through these metallic elements and go to the wall by the outlet, or does it go to the grounding of the router? If the second option is true, can it cause any problem in the system when I don't have a grounded router?

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    The shield should be grounded on 1 end only and noise will be dumped to ground. If both ends are grounded there ends up being more noise on the line. The router if not electrically grounded would not be the problem because the cable should be grounded at the entrance to the home. – Ed Beal Aug 30 '16 at 13:30
  • @EdBeal Thanks. Currently nothing is grounded as far as I know. I guess my TV and PC are not prepared for shielded UTP, but I am not sure. My router does not have a grounded plug. – inf3rno Aug 30 '16 at 13:33
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    You can't ground a shield on patch cords etc. The shield you can ground is building cable where one end terminates at a patch panel. siemon.com/us/white_papers/06-07-20-grounding.asp – Tyson Aug 30 '16 at 14:54
  • OK, but do you have a solid reason to suspect that there's actually a noise problem with your cabling? – Carl Witthoft Aug 30 '16 at 15:21
  • @CarlWitthoft I did not even start to assemble the cables, wall outlets, etc... I just thought this is something important... Actually this is just a home network, electric wires, radar, etc... are not close, so as far as I know there should not be interference. Is this something I should not care about? – inf3rno Aug 30 '16 at 18:54
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Edit: Snip Tyson already linked Siemons paper.

That gives a pretty good idea of the setup.

In a nutshell the mechs in the patch panel are earthed via the patch panel to the rack frame which then should be bonded to a communications earth.

Not sure what standards are worldwide, in Australia the communications earth is bonded to the electrical earth at the switchboard or earth stake.

There will be relevant standards regarding distances, cable sizes and colours and so on. Should be covered under electrical or comms standards.

  • I am not sure I fully understand. For example by a keystone module like this: logicit.hu/shop_seopic/2717/Delock_86205/big/… and by a wall outlet like this: logicit.hu/shop_ordered/2717/shop_altpic/big/… the current would go from the shielding through the keystone module and the metal frame of the wall outlet and it would end up in the wall? Or would it stay in the cables because this keystone module is insulated and would flow through the PC, TV or router instead? – inf3rno Aug 31 '16 at 1:14
  • Note: this is still for a home network, I don't have a patch panel, rack, etc... It is much smaller... – inf3rno Aug 31 '16 at 1:16
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    @inf3rno why did you choose shielded csble? Most home networks use UTP. You ground the shield at the patch panel, not at the end with wall outlet. It true tho most people don't use enterprise grade patch panels at home. – Tyson Aug 31 '16 at 2:45
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    It's fine. Shielded even without earthing has better performance with noise than UTP, nowhere near as good as proper earthing but it's ok. Nothing will get damaged, stress less. The shielding essentially just shunts noise to earth, it is not going to blow anything up. – D-on Aug 31 '16 at 13:26
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    @inf3rno home networking equipment doesn't have grounding connections. Your best route at this point is ignore the shield. Cut it back and skip grounding it. To properly ground it, you need components that don't exist at the home networking level. – Tyson Aug 31 '16 at 13:33

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