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Hi I'm going to install 5 Ethernet sockets in my house using cat5e shielded cable. I decided to use this because the sockets will be on the second floor and the most practical way up is within a trunk along with some mains wiring.

The cable will be terminated at the router and at the Ethernet faceplate. What can I use to earth then? The faceplate/router are both plastic hence no earth wire needed.

I can't use the earth wire within the main socket can I? I figured it will be very very dangerous. I don't want to be connecting to the earth block on the mains either since I totally incompetent when it comes to mains electricity.

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Earth? Does this refer to grounding? –  nicorellius May 20 '10 at 20:03
    
yes that is grounding! Why is it not the same? –  ageis23 May 20 '10 at 20:13
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Earthing is referred to as grounding in some countries. They are the same. Shielding is protection from radio frequency (RF) interference, usually by a foil wrap around each pair or around the whole bunch of 8 wires (inside the sheath). Shielding works better when earthed (arguably it does not work properly when not). Earth wire of the mains would be suitable assuming a) you can connect this safely, b) you only earth in one place. Grounding the shielded cable will NOT earth your PC at all, the earth wire of the power cable does that, or PC must be double insulated (eg if a laptop). Use UTP. –  AdamV May 20 '10 at 21:48
    
@AdamV please post that as an Answer so I can upvote you for credit. –  Spiff May 21 '10 at 5:53
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2 Answers

up vote 2 down vote accepted

Earthing is referred to as grounding in some countries. They are the same.

Shielding is protection from radio frequency (RF) interference, usually by a foil wrap around each pair or around the whole bunch of 8 wires (inside the sheath). Shielding works better when earthed (arguably it does not work properly when not).

Earth wire of the mains would be suitable assuming a) you can connect this safely, b) you only earth in one place. Grounding the shielded cable will NOT earth your PC at all, the earth wire of the power cable does that, or PC must be double insulated (eg if a laptop).

Use UTP

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Yes the pc power cable provides earthing. The chassis of the pc is already grounded. Would my cable be grounded if I just connected to my lan card? Isn't that earthed? trouble is am not an electrician so am not really supposed to be messing with the earth block. I have already brought the shielded cable and can't return it. Was very expensive. –  ageis23 May 21 '10 at 12:29
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I would not suggest grounding the shield on the router end.

If for any reason the ground potential of a computer on the second floor is different than the ground potential of the router, then a ground loop will be formed via the shielding, possibly causing damage to either the cable or the router or the computer.

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ok but then how is it properly shielded then eleven81? In other words, do I just wire the Ethernet jack then terminate it at the router using RJ45 plug then use a shielded patch cable to connect to my pc? My pc will be effectively be grounding the cable right? –  ageis23 May 20 '10 at 20:21
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