Can I run CAT6 FTP cables beside to electrical cable (220v 1 amp) in same PVC Trunking ?

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    Where are you on this planet? Is running a second conduit an option? Is this an indoor or an outdoor run for that matter? – ThreePhaseEel Dec 22 '19 at 20:23
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    What is the voltage rating and are there separate box areas at each end to separate the voltage connections from the data. Other than that we would need to know where in the world you are as 3phase asked, different rules for different areas. – Ed Beal Dec 22 '19 at 20:37
  • "I plan to kill myself or set my house on fire. Is this a good way of going about it?" – Valorum Dec 25 '19 at 2:11

Absolutely not.

Low voltage (LV) and mains cannot share a conduit.

Further, you cannot attach anything else to the outside of the electrical conduit. So forget about ty-wrapping the LV cable to the outside of the conduit...

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    Define: "conduit". If the OP is from Western European countries where wall-mounted trunking is commonplace (and it is permissable within the local building regs to carry mains AC, ethernet, phone lines, TV jacks, etc all simultaneously) then I can see why people refer to it as a conduit - whereas in the US conduit tends to refer to much narrower flexible tubing not intended for carrying more than a couple of cables - and both are made of PVC. This is an example of a multi-media + mains trunking: lindrickelectrical.co.uk/lighting-gallery/commercial-12 – Dai Dec 23 '19 at 22:02
  • @Dai -- "conduit" in the US is a tubular raceway, made from metal or plastic (the latter is often PVC, but glass-epoxy can also be used), either rigid or flexible, that can be used to carry conductors or communications cables, and can be installed either exposed or concealed. The closest US equivalent to European-style "trunking" is a product called surface raceway that provides a rectangular or molding-shaped channel along the surface of the wall that can carry mains or LV wiring, or both if the system has dividers in it to provide separate mains and LV compartments – ThreePhaseEel Dec 24 '19 at 19:35

You can run cables parallel outside conduit. Ideally a few inches apart but in practice right next to each other is usually OK.

But you can't run them together inside conduit. Plus, inside conduit you would be better off for the electrical cable using individual wires (appropriately sized & rated) instead, which is not an option for the CAT6 anyway.


Not in the same conduit as 120 or 220 - 240VAC, no.

Parallel to is no big deal, people who fuss over things that will generally have no effect do like to keep a foot/30cm between them, ideally, but in point of fact the signal design is such that interference between 50/60 Hz powerlines and 100+MHz network wiring is not really a problem.

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    From my own experience doing office installations it can make a difference. I've had lines fail to real 1Gbps due to interference when tested, and moving the line over slightly fixing the problem. Incredibly rare, and entirely possible things other than the mains was the cause of interference mind. – Trotski94 Dec 23 '19 at 8:37
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    Mains power is 50/60Hz, but that doesn't stop any device to either intentionally (powerLAN adapters) or unintentionally inject higher frequency noise into the power network. – Pelle Dec 23 '19 at 13:23
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    ...which the differential signal twisted pairs largely reject, by design. Incredibly rare matches my own extensive experience of many cable segments attached to smart switches that report error rates. – Ecnerwal Dec 23 '19 at 14:31
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    Years ago, when the company I ran IT for built a building with an office in the front, I specified the power and data conduits buried in the concrete slab to be a foot apart. I know it probably would have been OK a bit closer, but there was just no reason in my mind to push it, given that future improvements in network speeds might make newer technology more sensitive to crosstalk than the then-current tech. – Monty Harder Dec 23 '19 at 18:22
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    I've seen trouble. There was an IIRC 440V 400A power bus up near the ceiling. Some electricians hooked up network wires--doing things like throwing a wire over that power bus to keep it out of the way. Despite everything they did it worked, but with a high error rate. Note that this was 10/100 base-T, not modern stuff. – Loren Pechtel Dec 24 '19 at 5:35

An important question for you to ask is this: what is the difference between Cat5e and Cat6?

The answer is shielding. Cat6 adds a layer of shielding over Cat5e. That shielding is designed to reduce electromagnetic(EMF) interference so you can get more signal through it. Cat 7 and 8 add even more shielding.

Electrical wire is a significant source of EMF interference. The more your wires run unshielded and parallel, the more interference they will get. Mere perpendicular crossings are generally limited in how much interference they produce (although you should still limit exposure). As such (ignoring the electrical code), you will render your Cat6 unusable, especially if you want to run 10gB Ethernet.


I cannot speak to building codes (though I was always told that running low-voltage wiring near high-voltage wiring was a really bad idea, in case of a fire or other damage-- in particular, never do this on either the interior or exterior of a building where they could be struck by an errant forklift or car, and short through each other), but I CAN talk about the signal issues.

Ethernet cables contain eight conductors, formed as four twisted pairs. The idea of twisted pairs is that they are used as a balanced line, where one line in the pair carries a positive signal, and the other line in the pair carries the inverse of that signal.

Ethernet jacks, meanwhile, are implemented using magnetic isolators-- usually just called "magnetics". These are tiny air-core transformers, built right into the jacks.

The idea is that the positive and negative signal, applied to the coil forming one side of the transformer in the jack, produce a voltage in the coil in the opposite side of the jack.

Meanwhile, any external noise will introduce a voltage of equal sign and roughly equal magnitude in both lines, such that the net voltage across the lines in the coil due to the noise is very close to zero, and therefore the voltage induced in the opposite side of the magnetic isolator is also very close to zero.

Notice the word "roughly".

When an unshielded Ethernet cable is VERY close to a noisy line-- either an electrical line, or another unshielded signal cable with similar twist rates but higher power-- then the difference in the noise power induced in the two wires in the twisted pair can be significant enough to induce a significant voltage across the magnetic.

Ethernet energy levels are fairly low partly to ensure that adjacent Ethernet cables in a trunk can coexist without much crosstalk. But with power lines, antenna feeds, and so forth, this can be an issue.


The answer is: NO! Due to the emg interference.

  • Hello, and welcome to Home Improvement. I think you mean "EMI", but that's actually a minor concern; Cat6 cables are extremely well-protected against interference. And, you should probably take our tour so you'll know how best to contribute here. – Daniel Griscom Dec 27 '19 at 12:01

NEC 2020, and I don't think it's changed for the last 20 years


Article 300 - General Requirements for Wiring Methods & Materials 300.3(C)(1) Conductors of different systems 1000 volts or less

Conductors of ac & dc circuits rated to 1000 volts nominal or less, shall be permitted to occupy the same equipment wiring enclosure, cable, or raceway. All conductors shall have an insulation rating equal to at least the maximum circuit voltage applied to any conductor within the enclosure, cable, or raceway.

  • So first off there is no NEC code prohibiting you from doing so. If there is then someone should specifically reference it. No one has in any of the responses here. Any many of the responses are downright poor.
  • of logical importance: occupy the same enclosure, cable, or raceway; If you believe some nec code prohibits from doing what was asked then that would also have to mean when current carrying conductors didn't ALL operate at the same [nominal] voltage then we would have separate conduits for 120v vs 208v vs 240v vs 480v. That is not the case. Per 300.3c1 everything being less than 1000 volts it's simply the minimum wire insulation rating has to be observed.
  • Cat5e and cat6 and any other Ethernet cable is all rated to 300v. I believe RG-6 coax is as well. If you find a specific brand with inking saying to 600v then great even better but i don't think they exist.
  • https://www.mysouthwire.com/medias/sys_master/product-specifications/product-specifications/hd8/h0c/8858069565470.pdf
  • All romex (nm-b) and any pull wire like thhn is all rated to 600v. For any U.S. household which is usually 240 volt and below you basically have nothing to worry about with regards voltage and hazards. Only if your 600v rated romex was being used for 480v then you would not be able to run a cat6 cable in same enclosure, because the cat6 cable insulation is only rated to 300v.
  • as for signaling and quality of over the CAT 5e/6/7 or RG-6 cable, there is no hazard once the insulation requirements are met. At most if it is signaling for something important, to some legally required system or emergency system as called out in NEC section 7 then it would be reasonable to not run your cat 5/6/7 or rg-6 in same conduit because the system that goes to is that important. but the NEC is not concerned about your xfinity and internet signal quality.
  • the running of cat5/6/7 or rg6 next to romex and/or wire in conduit is blown way out of proportion. If it were anywhere close to true then every commercial network closet with a rats nest of cat5e UTP all run intertwined and velco strapped with 120v and 240 power cables to equipment would not work. They work just fine.
  • it is the twists per inch that differentiates cat 5 vs cat6 vs cat7 and not necessarily cable shielding. There is UTP (unshielded twisted pair) and STP (shielded twisted pair) which is independent of CAT-#.
  • the best way to go in any event is with STP (or FTP) or quad-shield coax. But with FTP or STP you have to use the corresponding metal rj45 connectors to maintain the shielding. Or you can just buy a 100' STP pre-made cat6 cable. Likewise with coax simply use RG6 quad shield. Either of which, having a 300v insulation rating, is thus permitted to be run alongside your 120v or 240v wires in your conduit. You would then really only need to worry about conduit fill. for cat6 @ 1gbps I think u would be fine but if you're wanting to do a long run at 10Gbe speeds then I would definitely do FTP or STP.
  • Your Code cite is inapplicable to communications cable. 800.133(A)(1)(c) governs the OP's situation, and prohibits the mixing of mains wiring with communications cabling unless a listed divider or permanent barrier is present in the enclosing raceway to separate the mains and comms wiring. – ThreePhaseEel Dec 28 '19 at 21:22

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