[SOLVED] Can ungrounded STP ethernet cable damage equipment?

[warhaug]

Hi.

I am currently upgrading my home network.
When i built my house 5 years ago i ran 1 or 2 ethernet cables from every room to a central in the basement.
I now have 18 ethernet wall outlets here with cables going to a switch before the router.
I now wanted to clean up the cabling on the wall, and bought these https://www.kjell.com/no/produkter/...nklet-sstp-nettverkskabel-cat.-6a-05-m-p61940.
I did not find any UTP cables like these and thought it would most likely be fine.

But then worry strikes at night. Can the shielded cables damage my networking equipment. Cables are sort of "cheap", the rest is not '.
I bought 10 cables and was going to buy the rest after testing the length, but now i consider throwing them away.

Google as usual puts up a jungle of information.
The shielding in ethernet cables actually have to be grounded to function.
I have considered myself a true computer geek for 30 years now and have never heard about this at all. A bit ashamed now.
But hey, everyday you learn something is a worthwhile day.

There is a lot of seemingly proffessional pages out there who say that if grounding is not done properly, then actual hardware failure can be the result, even fire.
I understand that the lack of grounding can cause interference and a bit slower network but actual damage?



Are there any serious danger for equipment due to ungrounded STP cables?

 

[bill001g]

It is actually extremely complex to get sheilded cables to work correctly. They are mostly used in industrial environments or where you want to keep the ethernet signal inside the cable not so much interference coming it....like ethernet placed in a airplane.

I only speak english so I am not sure what you linked. First be very sure that the cables themselves are copper and not CCA.

If these are patch cables they should have metal end on them that link to the shield. Now these actually only work in equipment that has a metal tab inside the ethernet jack to make contact with it. This is very very rare except in specialized equipment. So your machine is not actually in contact with the shield anyway. Shielded cable is more used between patch panel in data centers and then unsheilded cable is run the last short hop to the equipment.

To be properly installed the shield must be connected to a ground on both ends of the cable. This is to avoid ground loops. In addition it must be a completely separate ground form the electrical power. So you can't just use the grounding connector in the power outlet you must run a dedicated ground wire to each ethernet jack. Not very practical in a home installation but actually very common in large data centers where they ground the racks to a special grounding bar.

So what happens if you do not ground the shield. Then the problem is that it acts as a antenna and can actually attract interference. This interference will just corrupt the data not hurt the equipment.

BUT this is all a bunch of crap that cable vendor do to confuse people and make them buy stuff they shouldn't. The so called interference shield cable is used to prevent is extremely rare even in business installs. When you consider the number of unshielded cables packed into just 1 rack in a data center very close to power cables and other data cables. In a home environment it is pretty much non existant. So problem with installing shield cable in your house is it just makes your wallet lighter. There is no problem to fix in the first place and if you install it wrong (ie not grounded) it does not matter because there is no signals for the shield to act as a antenna for.

 

[warhaug]

Thanks for your quick reply.

I found the datasheet for the cable in english. https://www.kjell.com/globalassets/mediaassets/745063_61940_datasheet_en.pdf?ref=272924E88B
It says its copper cable and the site is reputable enough here. And ~10USD for 0,5m does not seem like a "too cheap" option.
The switch is the only place they connect to that have metal in the ports.
The only reason i bought this cable in the first place was that i could not find any alternative in UTP.
I wanted the CAT6a cable and with the 90 degree angle. They appear less common than i thought.

Thank you for the elaborate and informative answer.