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A large quantity of assorted computer cables came into my possession. The collection includes almost every type of computer-related cable (video, USB, Ethernet, printer, audio and speaker, SATA, power, etc.). I'm focused here on just passive cables, nothing with active electronics or things like power bricks. They became dirty in storage and need to be cleaned.

Most of us have probably heard about washing a keyboard in the dishwasher, and now I am wondering if the same method can be applied to dirty cables. My assumption is that because the older PS2 keyboards used in these dishwashing experiments have their own cables attached, what could be the difference?

Some of the possible concerns I can envision with using a dishwasher to clean them:

  • Cable construction could be different from a keyboard cable and the materials and fastenings might not hold up to dishwasher cleaning.
  • Dishwasher water temperature might be too hot for the materials used in some kinds of cables.
  • Immersing some kinds of cables in water might be bad for them, so some might be cleanable in a dishwasher and some not.

My assumption is that if all kinds of cables cannot be safely cleaned in this way, cables fall into just a few broad categories that drive what would be dishwasher-safe.

Questions:

  1. Dishwashability

    What characteristics (for example, type of construction or type of use), would differentiate computer-related cables that should not be cleaned in a dishwasher, and why?

  2. Scope of risk

    If a computer cable is put through the dishwasher and is adversely affected in a way that isn't externally visible (so it would be used rather than discarded), would it be only the cable that was affected? Or, is there any kind of computer cable where the kinds of adverse effects that could come from cleaning in a dishwasher could damage the equipment it's plugged into?

  • 17
    What kind of contamination are you trying to clean off of them? – PseudoSu Jul 28 '16 at 19:40
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    Indoor UTP cables (Category-5e/6) are not designed to get wet, and the sheaths are not really waterproof. Water inside the cable could cause problems by changing the dielectric properties of the cables. – Ron Maupin Jul 28 '16 at 19:51
  • 17
    you are kidding right? – Keltari Jul 28 '16 at 23:13
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    After your edited missing one: No. Don't do it. Absolutely no way. They're not cables, they're mains powered devices with cables hanging off them. If you plugged one in after spraying water all over it, you'd be lucky if it only fried itself and not you. – Chris H Jul 29 '16 at 8:29
  • 6
    Also do you really want that <s>sh</s> stuff getting into something you're going to use to wash your plates? They don't really sterilise you know. – Chris H Jul 29 '16 at 8:33
39

People do all kinds of things that aren't a good idea. If you read the answers on your linked question, you'll see that some people managed to get away with it and some didn't.

Dishwasher Use

Personally, I wouldn't use a dishwasher at all for cables (or other electrical/electronic components). The detergent requires very hot water to thoroughly dissolve and rinse, and can leave residue. It also tends to be a little corrosive. The plastic won't melt at dishwasher temperatures (unless a cable falls near the drying element), but it can leach out some of the plasticizer and make the plastic more brittle.

If you're going to use a dishwasher, I would limit it to molded cables like power cables or speaker cables, where there are just a few wires, the wires are heavy, you're dealing with low frequencies, and the molded connectors hermetically seal the ends.

Insidious Water

Where you have openings into the connector or cable, water (and detergent), is likely to wick in and will be difficult to remove. Capillary action can pull liquid into nooks and crannies, and into the cable, where evaporation can take ages. Using heat to dry it out may even make it worse because the cable can act like a heat pipe; the evaporated water spreads as a vapor to other areas, so you can end up spreading it more than getting rid of it.

In any kind of cable, residual water can, over time, cause the conductors to become brittle and more prone to breakage (through oxidation and chemical and electro-chemical reactions mentioned in the answers by txtechhelp, Nick T, and Tonny). The thinner the wires in the cable, the less metal they have and the more susceptible they are.

Different Types of Cables

If water gets into low frequency cables, it can shorten the service life of the cable, but it probably won't significantly change the cable's performance. Cables used for high-speed data communication are a different matter; the water, itself, can be an immediate problem because these cables aren't just wires and connectors. Their performance relies on electrical characteristics of the cable design. Water can affect those characteristics and degrade performance.

Cleaning Recommendation

What you're trying to get rid of is external. The cables should still be internally good. If you get water inside, you may create issues you don't currently have. A better solution is to just clean the cables externally by hand by wiping them with a rag and some isopropyl alcohol.

Risks

The risks relate primarily to the performance or service life of the cable. The only risk of damage I can envision to something other than the cable would be getting water inside the plug of a power cord. You could potentially get leakage currents that could corrode the wires or cause other problems beyond the cable, itself.

  • To clarify a point about residual water reacting with the conductors: the answer just refers to the potential action; the extent and location will depend on cable construction details that will vary from cable to cable. The insulation may do a good job of protecting the wire, in which case, exposure would be mainly in bare areas in the connector. Residual water in the cable might just be a source of moisture returning to the connector. The cable strain-relief might compress the cable enough to prevent water migration. So specific cables will be affected to varying degrees. – fixer1234 Jul 30 '16 at 9:52
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    Another recommendation, depending on the type of crud, might just be a rag and warm, soapy water. Just wipe the length of the cable with the rag, avoiding submerging the connectors. – user2943160 Jul 30 '16 at 19:04
20

TL;DR: buy a few bottles of 91% isopropyl alcohol and a small bucket, dump all that in there and scrub the cables in there, then do a sponge bath and wipe with a non-static producing cloth (paper towel for instance).

There's a couple of issues to concern with if you do wash them in the dish washer. First as you've noted, is the heat the coils or water can reach. Most consumer dish washers can operate up to 180 degrees F (for things like the sanitary wash), and usually spray hot water around 130 F. While the water temperature won't do much to the sheathing on the cables (like melt them), you might have issues later.

As an example, HDMI has an operating temp of 80C (176F), so if you did a sanitary rinse on the HDMI, you might change the physical properties of the wires themselves and make them not preform to the spec. If some cables can't operate to spec they won't work at all.

Another issue is in what condition the sheathing of the cables are in. A lot of cable types have a cheaper grade plastic rubber coating that will crack or melt easier than other types, especially under non-ideal conditions (which you're essentially shoving the cables in a thunderstorm in the middle of a desert). There's also the potential the cable might fall through the racks and land on the heating element, and melting completely (I had a lid do that, melting plastic in a dish washer is not a fun smell).

Additionally are the detergents you would put in. Putting anything in your dishwasher that's not a dish detergent might mess up your dishwasher, while putting dishwasher detergent might mess up the cables or connectors (salts + metal + water = no good long term).

Answering your questions

Power cords with AC/DC Transformers attached

Would most certainly fail after being washed. Water plus heat on small IC's can short them out or just completely destroy them.

If there is concern about the temperature of the dishwasher (although I cannot imagine it hurting the cables and not a keyboard), can they be washed by hand?

Yes, you can wash the cables them selves. For the electrical contacts or other small electrical circuits, use isopropyl as it's effective at getting grime and dirt off and doesn't interact with the electrical components (plus it evaporates in minutes for small amounts). If you have a lot of cables that are grimy, you can get a small bucket and fill it with the alcohol and scrub and clean them that way.

If there is any water left in the cables after several weeks of drying out, could they damage the electronics they are plugged into? Or will they simply not function?

If there's any water left in the cables after several weeks of drying out, then chances are there's a small puddle in the cable or you have them in a humidor. Water isn't good for electronics because it conducts electricity and can short out whatever component you have.

As an extreme example of what might happen: water shorts the USB +/- power lines when you plug it into your laptop creating a feedback loop on the bus which would actually cause the bus to blow up (literally pop the IC's).

For reference, I've also put some common operating temps with a few of the cables from your list:

  • HDMI cables: 80 C
  • SATA cables: 80 C
  • Cat 5e/6 ethernet cables: 60 C
  • USB cables: 50 C

Sources: my military experience taught me many ways to clean cables covered in sand or other mystery goo (as well as how NOT to clean them).

  • I do use isopropanol to clean label/tape gunk of cables, but to clean rodent mess off I'd probably spray some bleach/detergent kitchen cleaner onto a rag and throughly wipe with that. Then wipe with a damp cloth. If the rodents left liquid contamination, the residue is more likely to dissolve in water than than alcohol, solids will soften at least as well in water. For the contacts, IPA is indeed the way to go – Chris H Jul 29 '16 at 8:32
5

Keyboards are much easier to dry after washing (that said, I have ruined one keyboard by washing it). Your cables will suck water inside them through the connectors due to temperature differences inside your dishwasher, like in the "thirsty bottle experiment": enter image description here

That water will stay inside the cables forever, rotting them from inside.

So stick with non-corrosive substances like isopropil alcohol, and wet the connectors without dipping them into the liquid. If the tarnish persists, rub gently with a cotton swab.

  • 1
    Yep. Using dishwashers (without chemicals, without food related things in them at the same time!) has long been practiced by collectible electronics enthusiasts, but removing large transformers and other items that could soak up water is always recommended. Long cables certainly can and will soak up water! – rackandboneman Jul 29 '16 at 14:24
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Just like with a keyboard, it can be a bit of a crap-shoot. Might work, might ruin. That said, here's some of the effects that water might have on a cable and why it might/might not matter.

Mechanical

Depending on the design of the connector, water might be able to infiltrate into the cable. Connectors that are injection-molded around the pins will be able to prevent most water from getting into the jacket area, and there isn't much correlation between the type of cable and how it was assembled: you need to look at them and see for yourself. If there is no obvious way to disassemble it, if where the wire bundle enters the connector and inside the connector looks sealed, it might resist water.

If there are any holes and water can get inside, it might "wick" inside, both between the insulated wires, and also between the individual strands in stranded wire. Water there may or may not matter, depending on...

Electrical

Any "high-speed" digital cables, e.g. SATA, USB 3, HDMI, DP, require some fairly specific characteristics to shove as much data across them as they do. Water is sometimes conductive, but it also has an extremely high dielectric constant, which is a sensitive value in many transmission lines. Among other things, water in close proximity to high speed conductors can artificially "lengthen" them to become out of spec. Because this is so sensitive to what you're connecting, the design of the cable with regard to something it shouldn't have to deal with (a dishwasher), it's anyone's guess.

High-frequency analog cables, VGA, RCA for video, might exhibit strange "ghosting" or other effects that you'd occasionally see in extremely long cables.

And while low-speed cables should be fine from a signals perspective, if sustained voltage is held across some wet contacts, they will eventually corrode because you're making a little plating setup, coating one contact with the other.


Anyways, the cable itself is almost certainly a non-issue; it's the connectors. If they aren't what's wrong with the cables, bag or wrap them tightly and things should be fine. If they are dirty, maybe you could try sealing where the contacts are and the cable meets the connector body temporarily with something like hot glue (pries off pretty easily).

2

With the exception of network cables (whose underlying wires are exposed; see comment by Ron Maupin), none of the cables in question have any active components or exposed wiring that could be damaged by washing (even at elevated temperatures). Just make they're completely dry before you use them.

For cables with female or otherwise recessed connectors, there's the possibility that water will stay inside the connector for a while, but a few days in sunlight should be enough to get rid of most of the residual water. Any remaining traces should be completely harmless, though additional caution is needed for cables that connect to mains, such as the IEC C-series power cables you mentioned.

Also, dishwashers don't typically operate at such high temperatures that they could damage the cables; residential dishwashers typically top out at about 170 °F, while plastic doesn't normally melt until past the boiling point of water. (Some lower-quality plastic may noticeably soften at these temperatures but I doubt that a one-off washing process will do much damage.)

As for the network cables, I'd try to wipe them with a damp cloth instead of washing them, as they can be damaged by water ingress.

  • What is so special about network cables? Is moisture egress more difficult? – user58446 Jul 28 '16 at 20:07
  • The underlying wires are exposed unlike with most other cables, allowing water ingress that can damage the twisted pairs and shielding. – bwDraco Jul 28 '16 at 20:08
  • I guess I am asking because I assumed none of the cables are waterproof, and all of them would get water inside the sheath. I thought it might be difficult to dry them out of course, but I am not sure what difference exposed wires at the tip termination of the network cables would make... wouldn't they just dry out faster?! – user58446 Jul 28 '16 at 20:29
2

Your mileage may vary.

It is a bad idea for any cable that has wires consisting of 2 different metals. E.g. many cheap UTP cables don't use solid-copper wires but copper-clad aluminum.

You'll get a redox reaction on the boundary layer between the metals which will seriously comprise the signal quality of the cable.

This even happens without washing them. I've seen 10-12 year old Cat5e cable degrade to the point it wouldn't do Gigabit anymore (even on distances less than 5 meter). That was in normal indoor building use in the Netherlands (not exactly tropical humidity levels.)
Washing would make that happen overnight.

Same thing could happen to the soldering joints (or crimp-joints e.g. in RJ45 connectors) where the internal wires are attached to the connector pins.

You would be pretty OK with cables that have sealed connectors.

It ain't a good idea for optical cables either because of the potential for abrasives in the detergent to scratch the ends of the fibers.

I say: Try it.

The cables are a write-off anyway. You might be able to salvage some of them.

I would mark the "treated ones" so if they act up later I could easily identify which ones had the treatment and throw them away if they prove themselves to be unreliable.

P.S. It's probably best to use very little detergent or none at all. Use something biological: Less chance the chemicals in the detergent can react with the plastic of the cables/connectors.

1

Shockingly enough, there's specific products meant to clean devices like this. Depending on the nature of the contamination - what you're looking for is called contact cleaner. I suspect many of the cables would not be hurt by a dunk in clean water but using a specialist product would be a good idea.

Those oldschool keyboards are large, mechanically simple, and terribly robust compared to modern keyboards

I'd also point out things like speaker cable may be simple/cheap to replace.

As with any cleaning product, spot test before use.

I suspect a dishwasher wouldn't be as efficient as clean (preferably distilled) water or better yet, high strength alcohol, and depending on water hardness and the cycle, might make things worse.

  • Something like a Model M keyboard is also very easy to disassemble: basically just a few nuts that need removing, and it comes right apart. You can literally take off the exterior keyboard casing and the key caps, blow (compressed air) or vacuum clean the keyboard interior while washing the exterior parts before allowing them to dry thoroughly, never getting water anywhere near anything electrical. – a CVn Jul 31 '16 at 11:42
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To me, this sounds eerily like my experiences with getting a wireless phone wet. I worked in a national call center (in USA) for a wireless phone company, so I heard lots of comments from many people.

From what I can tell: if you get your cell phone wet, you should avoid turning it on (even once) for a few days. The idea is to let any remaining water evaporate: leaving it in sunlight might be helpful (or might cook the phone). Then, you have about a 50% chance of the phone ever working again. If it does work then, it will often work for a few or several months later. However, expected life span seemed to be typically reduced, substantially.

I thought about this, and I think one reason is that when water enters the phone, the effect is often random. Basically, as a conductor, the water causes electricity to go where it is not supposed to go. This tends to cause enough problems that the phone typically turns off, but the presence of long term damage would vary based on where the prohibited electricity ended up going first. That would vary based on exactly where the water entered the phone first, and possibly based on what the phone was doing. Since that is likely to be different for different phones, and the entire process is typically an uncontrolled accident, that's why I refer to the results as essentially being random.

Most of us have probably heard about washing a keyboard in the dishwasher

The results I would expect from this is that some people would have no problems, while some people would have some water get into the keyboard, and not evaporate in some cases, and have water cause a problem.

If you want to gamble, go for it. Your call.

As for me, I typically try to keep my electronics aware from any form of liquid. The proposed idea (placing an electrical component, in this case the wires, in a dishwasher) is a complete violation of the concept of the principle of safety for electronics (totally avoid liquids). I do believe that is why Keltari's comment (“you are kidding right?”) received so many up-votes. I can understand if such a comment is confusing to someone who hasn't been taught the same things I was when I was young. Basically, the idea of cleaning keyboards (which some of us might never do until the keyboard is replaced), by using this technique (using in a dishwasher where water gets splashed in all sorts of directions), is absolutely opposed to the proper handling procedures that many people have been taught, and live by, with results of electronics typically lasting as long as we want them to (until they get replaced).

Washing electronics in a dishwasher sounds like an invitation to damage equipment (bad scenario), or risk random problems immediately, or risk random problems down the road (after remaining water, which might be vaporous, finally gets heated enough (by active electronics)) to go somewhere that it shouldn't. The metal of connectors might be more prone to a chemical reaction (essentially rusting). And the dishwasher is meant for dishes, which can withstand heat and are typically rather big. If a piece of wire came loose and went somewhere bad, clogging a gap or getting tangled around the dishwasher, you could find the cable gets damaged or the dishwasher gets damaged.

  • The thing about cables is not that water will conduct electricity and short things, it is more that water changes the dielectric properties of the cables. Inside the cable sheath, the individual wires are insulated, unlike what you find on a circuit board. Many indoor cables that appear to have waterproof sheaths don't really. If water somehow migrates into the sheath, it is very difficult to get it out again. – Ron Maupin Aug 8 '16 at 3:48
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    @RonMaupin : That too. I saw there were several other answers. I wasn't trying to make mine appear superior, as if the others were wrong. I noted multiple thoughts on why dishwashing cables may be undesirable. I don't claim scientific/electrical expertise to correctly assess which reason is most likely to be the true cause of a negative impact. My main point was just; there are multiple reasons to expect possible negative impact, so thmye recommendation is to avoid this activity. Successfully avoiding this damaging activity is more important to me than selecting which reason why is the best. – TOOGAM Aug 8 '16 at 3:59

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