Is it necessary to ground a metal Knock Out Box used solely for POE Ethernet wire?


My house's builders seem to have cut one of the Cat-6 internet cables somewhere along it's run from the basement to the data hub where all of the other cables converge. It might even be between the floors. This is a low voltage circuit.

The basement outlet is about 12 below and about 25 feet along a single wall from the data hub box. (The Cat-6 cable does not turn corners. It goes up and over.) I have access to the other end of the cable in the data box.

Is there a device that I can plug in to either end of the cable and then track the path of the cable from on top of the dry wall? I hate to punch a bunch of holes in the plaster when I have no idea where the cut is. If I could punch one hole, I could splice the break with a male-female connector, put it back in the wall, and patch over...

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It is presumed that your question is aimed at minimizing Electromagnetic Interference (EMI). The answer is VERY difficult to be precise for your case. EMI depends on many factors, however, for your case the variables you should be interested in are: the separation between the cables and for how long the two cables run together. Separation is inversely-proportional (not linearly though) to EMI, and distance run together is proportional (ibid on linearity) to EMI.

It also depends on what you connect to the power outlet! If you running a washer or a vacuum cleaner, I would expect to see more re-transmissions in your Ethernet cable as a result than if you were to plug in your computer to the power outlet.

Unfortunately, the metal box won't buy you much. (However, if you do, make sure it is grounded to the same ground as the power cable.) The damage is really done in the UTP running parallel to the power cable vice where it is terminated. In many shipboard design...

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In every room of my home, there is an outlet with three connections: coax, Cat5e RJ45, and an RJ11 for phones. I unscrewed the outlet and noticed that all of the wires seem to be heading up towards the attic.

I did a very brief check of my attic (just took a peek from the ladder), but all I could see were valleys and mountains of insulation. If the wires end here, I would have to literally go hunting for them under the insulation. Why would the wires terminate here? Is this common?

I've searched all over my house, but there is no central point where the ethernet cords lead to.

I'm guessing the wires end somewhere in the attic, but I can't fathom why the master builders would lead them all up here and then stop. Is it common for a prewired home to leave it up to the owner to further wire them to a central location...

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Currently I have, courtesy of the last owner, 3 wires running to the "socket" behind my TV. It's a coax and 2 audio cables (image below), and they go to the fuse box/meter box in the hallway. . I'm not sure how they run, but at least: in the wall they go up, through the ceiling (probably some turns there), and then back down into said box. The yellow PVC tube they run trough is about 1.5cm in diameter (also see below).

Now I don't need an audio cable there at the moment, but I DO need network. I have a "wire pulling spring" (not sure that's the correct term). I figured my options are:

Attach the spring to one or all wires, pull everything out, pull everything I need back with the spring Attach new wire to audio wires and pull the audio out and the network in with one action Attach the spring to the audio wire, pull the spring in and the audio out in one go, then pull the network in with the wire pulling spring.

Option 2 and 3 mean that if I do get stuck, I won't be...

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If you have an ungrounded system, there's nothing you can do with it, (the grounding conductor)anyway.

Don't assume that your system is ungrounded, just because you have only 2 conductors in the fixture box. If you have a metallic raceway system, the boxes & the raceways (RMC, IMC, or EMT) will be your equipment grounding conductor. In that case, you must bond the fixture's grounding conductor to the metallic box; this can only be done legally in 1 of 2 ways.
1) With an identified (this means green) 10-32 grounding screw.
2) With an identified (see above), listed, grounding clip that attaches to the edge of the box.

Of the 2 methods, the screw is the easiest and most effective. Never, ever, use a sheet metal screw to attach equipment grounding conductors to metallic boxes (no matter what the kid at the home improvement store tells you).

With an ungrounded system, the grounded conductor (the correct term for the system “neutral” – because it is the...

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The installation infrastructure (towers and masts), as well as antennas and the router itself must be properly grounded, and lightning arrestors must be installed on all external antenna cables (near the antennas or on the antennas themselves) to prevent equipment damage and human injury. Note that lightning arrestors will not have any effect if not grounded.

Use 1 AWG (7mm in diameter) wire with corrosion-resistant connectors for grounding. Be sure to check that the grounding infrastructure you use is indeed functional (as opposed to decorative-only grounding present on some sites). For smaller devices you can use thinner wire.

Only shielded and outdoor usage Ethernet cables should be used, magnetic shield should be grounded via shielded RJ-45 connector or via additional wire that is soldered to RJ45 or ground wire. Grounding wire should be connected to RouterBOARD (to the mounting point where board is fastened to the outdoor box), this wire is...
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If you are worried about voltage losses in longer cable runs (and you should be!) then certainly feeding a higher voltage and converting down remotely is a good idea.

Simple: 7805 or 7812 regulator to drop from a higher voltage. Gets warm, wastes power, current in (at say 15v) is same as current out to device.

Slightly Harder: Something like this fitted at the remote end will take whatever's available from about 7v upward (this module goes to 24v) and transform it down to 5v.

It's a switching converter (buck converter) meaning it draws less current than the load. This is good. It reduces the losses in the wiring, and is even more efficient.

It's not exactly PoE standards compliant, it's not 48v, but it works.

I'm using some of those modules (and similar) to power remote IP cameras (draw 400-500ma, at 5v) from a centralised "injector" -- actually a hacked 8 port router with an...

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Grounding for safety (vs grounding for signal integrity, which is a whole different issue, see below) is primarily a concern for equipment in a metal enclosure. If there is a wiring fault inside the device (frayed wire shorting against the metal inside), then the outer shell of the unit may be electrified. Guess what happens when you touch it? Ouch! By having a ground path, you give the electrical current somewhere else to go (instead of through your body when you touch the device).

You will notice that most devices in a metal enclosure will have a 3-prong input power (if the power plugs in directly without an AC/DC power brick), and also a chassis ground screw.

If you are grounded through the power cord, the middle prong should be connected to the building's wiring and then to an earth grounding rod, assuming your building was properly wired using modern building codes. There are inexpensive testers that can check to make sure your outlet is wired...

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There are two different treatments you can have of this outdoor structure, and each has its own set of problems. Local codes will probably determine which you must actually use.

If you treat the outdoor structure as a separate electrical system, it must have its own ground and panel. In that case, your LV Ethernet cable can potentially support the voltage difference between the two electrical system's grounds, which in the event of an electrical storm can become a huge voltage. So there's a potential life safety issue if you touch that cable, or even something downstream of it. Your entire Ethernet network could end up spreading a lot of charge. You need input protectors on both ends of the cable, MOVs properly grounded. Check your local codes, because this might simply be something you're not allowed to do at all.

If you treat the outdoor structure as an extension of the main structure's electrical system, you bring a ground wire to it. In this case, the "ground" of the...

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