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I've read that you cannot mix power cables and low-voltage cables (in my case: HDMI, CAT6, USB) in the same raceway (that plastic conduit that stick to the outside of the wall)

But in every home I've been to, people have 1 raceway from their wall-mounted TV. Even products on Amazon show 1 raceway running from the TV.

So I am confused, is it allowed or not?

To clarify, I want to hang a TV on the wall. It will have:

  • 2 power cables
  • 1 HDMI cable
  • 1 USB cable
  • 1 CAT6 cable

Can they all run within the same plastic raceway stuck to the outside of the wall? I have never seen a setup where they'd have 2 raceways for this purpose.

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    I wouldn't count on anything you see on Amazon being the gospel according to code.
    – FreeMan
    Mar 15, 2022 at 16:16
  • Think I read they cannot be together in a junction box, but if this extends to raceways/conduit do not know. Code usually does not mention low voltage(<50v).
    – crip659
    Mar 15, 2022 at 16:41
  • If it's on Amazon it must be true... That's the Internet after all! (Oh, wait... so is this!)
    – gnicko
    Mar 18, 2022 at 19:24

3 Answers 3

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Those rules apply to building infrastructure. Typically "inside the walls" but also surface-mounted conduit and related infrastructure.

If your "raceway" is nothing more than a few velcro straps guiding a power cord and other wires along the top of a desk or fire place, it's absolutely fine. If your "raceway" is inside walls or if it includes any building wiring as opposed to power cords, it's absolutely not fine. In between is a gray area, and depends on whether your raceway more resembles a cord organizer or an actual raceway.

The really gray areas are surface-mounted plastic raceways sold as cord organizers. If you use a 3-foot piece to decorate a power cord and HDMI cable dangling from a TV to an outlet on the wall below, it's probably a cord organizer and probably fine. If you use one to guide a 100-foot extension cord from one end of your house to another, it's probably a raceway and you shouldn't mix LV wiring, nor should you enclose an extension cord that way at all.

If my pronouncement (as inspector of nothing) is worth anything to you, the specific product you linked in your question, used in the specific way depicted in the photograph, ie to conceal a couple of cables as they travel several feet along a wall, open and visible at both ends and never entering the wall, is not subject to building or electrical building codes and looks perfectly safe to me. It's very much in the gray zone between "concealer" (as marketed) and conduit, but it looks like a concealer to me. If a real inspector took exception to it, you could just pop the cover off for the inspection.

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    It's def not code legal to have LV and line voltage cables in the same raceway/conduit, mostly for safety reasons. But there is another reason it's a bad idea: Electrical interference on the LV side. If there are any high amperage usages it can induce interference on the LV side. My rule is when installing LV and line voltage is to keep them 12" apart and if they need to cross, do it at a 90 degree angle. Probably over-kill, but not hard to do. Mar 15, 2022 at 18:04
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    I wouldn't worry about noise or crosstalk in HDMI, Cat6 or USB cables used for consumer purposes. They are all digital signals on balanced wires in shielded cables designed with this use in mind. EG a power cord and HDMI cable tied together and snaking their way down the pivot arm of a TV bracket or monitor to wherever the equipment is.
    – jay613
    Mar 15, 2022 at 19:38
  • Yeah no, AC power in the same cable organizer as data is not legit. Wires can melt down in cable organizers too. Mar 15, 2022 at 20:21
  • @GeorgeAnderson, the frequencies of line voltage and digital signal cables are so different that there won't be any crosstalk: line voltage is at 50 or 60 Hz, while HDMI, for example, runs at a minimum of 165 MHz. The only real crosstalk risk is between power cables and analog audio cables, giving you a bad case of mains hum.
    – Mark
    Mar 16, 2022 at 1:23
  • @Mark I get what you are saying, maybe I'm just being OCD but when I'm installing LV and line Voltage and then it gets covered by sheetrock, I tend to play it safe. Just me, just saying. You might be right, but at any rate, it's not code legal to run LV and line V in the same raceway. Mar 16, 2022 at 3:34
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What you're missing is a hidden receptacle behind the TV

Most of these competent installations provide only one in-wall raceway for signal cables - that is true.

However, what is not so apparent is behind the TV is a properly installed AC power receptacle in the wall. This is a standard installation procedure.

Often, the power outlet behind the TV is wired to a power inlet (inverse outlet, has prongs sticking out) near the floor. This is allowed per NEC 400.7. The point of this is to allow the TV outlet to be fed from a power strip, for surge suppression or control.

Many UL-listed "kits" are sold which combine both the outlet/inlet pair, and the large pipe for the user to fit low voltage cables. They are a few inches apart. In North America, anything installed in a wall must be approved by UL, CSA or ETL.

What about all the exceptions I see?

Well, there's no accounting for fools. Lots of people violate Code, and that does not mean it's safe or legal. They'll have problems selling the house and collecting insurance after a fire.

We also have adversary nations shoveling extremely low quality garbage into our markets, that is not UL/CSA/ETL listed. Consumer protection agencies protect our bricks-and-mortar retail channels. But mail order is "the wild west", including mail order that is drop-shipped through domestic warehouses. Amazon Marketplace (3rd party sellers on Amazon) is the poster child for this.

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  • Great, I've seen those on Amazon. Question: the in-wall power and the lv-cables are just hung lose in the cavity between the studs? Doesn't that go against the "careful, 1 wrong nail and you hit the power line" mantra?
    – Slav
    Mar 16, 2022 at 0:45
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    @Slav Different kits have different install methods but yes, some of them install that way. It's not the best idea for multiple reasons, but the risk is somewhat mitigated by the cable run being short and by that area below a mounted TV being an unlikely place that someone would want to hang something.
    – bta
    Mar 16, 2022 at 16:30
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    @slav there's no accounting for junk, but the UL Listed ones do it correctly. (and Code requires UL Listed ones, NEC 110.2). The "nail" rule is generally that wires will hang back at least 1-1/2" from the wall surface, so nails that short are low risk. UL certifies them as safe when installed correctly (which is a Code requirement 110.3), so leave the testing to them! Mar 16, 2022 at 18:13
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Some manufacturers (Legrand on their Cordmate product, not a recommendation) are taking the position that these products are not a raceway regulated by the NEC, but are instead a "cord cover" and therefore not addressed by the NEC.


From Legrand's website (Wayback link for posterity):

Q: Can you use CordMate at a worksite to conceal a TV cord? Is it not a violation of the NEC's requirement that you not attach flexible cords to building surfaces once you stick it to the building with the cord inside?

A: The use of the C100 CordMate product to cover a TV cord attached to the wall would be at the discretion of the local AHJ. The CordMate product is a cord cover. The use of cord covers is not addressed in the NEC or CEC. The NEC states that flexible cable is not to be attached to building surfaces, but does not address the permanency of the "attachment".


Their deference to the local AHJ is laughable, considering I know no one who asks for an inspection when installing their TV on the wall, but Legrand is a notable manufacturer of raceways, and presumably has done sufficient work to ensure they can manufacture and sell such a product in the US under a UL listing. It's worth noting their install instructions do specify one power cord, so to answer your original question, you likely need multiple "cord covers" to run all of the cords you listed unless the product you choose allows that many cords.

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  • Great info, thanks for that
    – Slav
    Mar 29, 2022 at 18:28

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