I am talking about mild “tingles” and not proper electric shocks. However, if anyone receives any kind of electric shock, the appliance should be disconnected immediately, and an appliance engineer called out. Mild electric shocks or tingles might not be taken seriously, but they can turn into lethal full mains voltage shocks at any time.
So never use any appliance even if you only get a mild shock from. Disconnect it immediately. The reason you get shocks from a washing machine, or any other appliance, is because it is not earthed properly.
Why Does an unearthed appliance cause shocks?
All large appliances need to be connected to earth for safety. The earth wire runs down the mains cable and then through the socket it is plugged into. If this connection becomes broken at any point in the machine, cable, plug or wall socket, then you can get the symptom of mild electric shocks.
The shocks are often mild, or just tingles because they are caused by small amounts of electricity leaking or inducing across to the disconnected earth wire and running through the casing. It’s a phenomenon related to eddy current, but it’s not necessary to understand the scientific reason.
Such an appliance poses a serious danger. Because the mild shocks indicate that the washing machine is not earthed it means that if a component inside the machine’s insulation breaks down, or a live wire comes adrift and touches the metal parts inside, then the low voltage current will be replaced by the full mains voltage – which can kill. Without a path to earth, the washing machine cannot blow the fuse, and instead could just work as normal but be lethal.
Plug not earthed?
The first thing an engineer is likely to check is the appliances plug. They would check inside the plug to make sure the green and yellow earth wire is connected securely.
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If it’s OK, then either the earth wire inside the mains cable could have a break somewhere inside and needs replacing, or it may not be connected inside the washing machine. (The latter is very unlikely, I’ve never known it, but it’s theoretically possible). Both can (and should) be checked with a continuity test meter by checking the continuity between the earth pin on the plug and the metal door hinge or another suitable bare metal point on the washing machine.
Moulded plugs
Most appliances have long since come with pre-fitted moulded plugs which can’t be checked. So if unable to check inside the plug the first thing an engineer would check is the continuity down from the earth pin as described above. If he had a good reading he shouldn’t need to look inside the plug anyway. If the reading was open circuit or high resistance, but the earth was connected properly inside the machine he’d cut off the plug about an inch down and replace it because earth wires can break at that point. If that failed to make a difference he’d replace the mains cable.
Extension cables
If the appliance is plugged into an extension cable then clearly there could be a problem anywhere on the extension. So an engineer would check the earth connections and continuity on the extension cable. Ideally ditch the extensions, they aren’t ideal on large white goods appliances. If one is necessary try another extension (but make sure it’s appropriate – appliances and extension cables). I have seen appliances plugged into totally inappropriate extension cables that are using 2 core cable with no earth!
Wall socket not earthed
Another possibility is a fault in the wall socket. The earth wire could be disconnected inside or the brass earth prongs inside could be worn or too far apart to grip the earth pin on the plug properly. Obviously you don’t mess with wall sockets. If you suspect a faulty wall socket get an electrician – not an appliance engineer.
Don’t confuse with static electricity discharges
If you get just a single short shock when you touch an appliance (possibly accompanied by a cracking sound) which doesn’t reoccur when you touch the appliance again this could be static electricity discharging from your body and is very different to this issue.
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Hi! i just got a new laptop which tingles me when it is plugged in, even when the socket is switched off. On battery power, it is fine. My husband was unable to feel anything. Then i told my electrician sister in Australia about it and she said it’s dangerous, don’t use it. I am on a 24 volt solar system. i have noticed a few other small appliances also tingle me when i plug them in. With some, i just turn the plug upside down and it stops. With the laptop, i can’t do that as it has a three-prong plug like the three-prong socket. I suspect the whole house needs grounding and maybe certain sockets need to be replaced. When i called the local guy who does electrical work he seemed to be in the dark about grounding issues. So then i unplugged the laptop from the powers-strip socket it was in and moved it to a different one and the tingling stopped. So perhaps the socket os faulty. Thank you for your nice, clear article.
I was called to investigate an instance of customers getting small shocks from a row of lighted shelves, they are about 30 shelving systems attached to each other in a row with 18watt flourescent tubes lined along the front. I tested between the earth at the hot at the main swith and got 115v which is good, then I used an extension cable and went between the hot and each of the shelves on each module and got 115v, I even scraped a bit of the paint off in some cases for direct contact. So every shelf is gorunded yet I got anoyher call of a customer getting shocked on a drinks display freezer, I cant seem to understand whats going on in that supermarket, any ideas or suggestions?
Hello Eric. Lighting isn’t what I cover, but could these shocks be static discharge by any chance?
Other than that if there is current running through the shelving due to an earth fault you should be able to detect it with a neon screwdriver, or one of those battery powered voltage detectors.
If it’s not static discharge and is leaking current or current migrating to casings or shelving it can only be an earth fault otherwise fuses would blow. Make sure the lighting is plugged into an earthed socket and any extensions used are earthed if they need earthing.
Hi! I have a small back porch. I have a stand up freezer, washer and dryer back there. The dryer is plugged in to a 220 all by itself. The washer and freezer share a electrical strip. Mt freezer has been zapping me. Not a shock, but tingling through my hand. Then the washer did the same. The washer had some water leaking from under it. We replaced the strip with a new one. Plugged therm in separated still did it. Even used another oulit, still did it! What is going on?!
The only thing that can cause a shock or tingling shock is either static discharge, which would only happen once and then if you touched it again right after the charge on your body would have gone or a faulty earth inside the appliance, in the plug, or the socket, or the house wiring. If you are getting mild shocks from any appliance you should stop using it and get an electrician. The first thing is to check the plug on the appliance (if possible) and then plug it into a different socket or extension cable. All the information is above in my article.
Hi, I’ve just got a shock off the inside drum of our washing machine, I’ve used a meter and it’s showing 115V. Any ideas what may be causing this?
It can only be caused by an earth problem as described in my article above, otherwise it should blow the fuse or trip the electrics. The only way I can imagine this being possible is if the drum was completely insulated from the rest of the machine and not earthed in any way but somehow a wire was touching the drum pulley. But I can’t think of any electrical wire or part that could be touching it.
That was my thinking too, the earth connection to everything seems fine, have metered out and everything metal within the machine has continuity with the Earth pin of the plug, equally I can’t see anything within the machine that looks wrong (snagged wires, etc). Could a heating element failure somehow do it? Thanks for your help so far!
Hello Chris. If the heating element is down to earth, or damaged exposing the inner element then it should instantly blow the fuse unless the socket it’s plugged into, or the washing machine plug, or any point on the cable or inside the machine is not earthed. The first thing an engineer would do is test the continuity of the earth pin on the washing machine’s plug to the metal casing on the machine or the metal door hinge. There should be virtually no resistance. If there’s a high resistance or open circuit it needs investigating.
After that they’d check the wall socket with a plug in socket tester.
Hi Andy,
Sounds like I’m on the right lines then as I’ve checked both of those things and they’re both fine, got a plug in RCD tester too and tested in the socket it’s plugged into and it trips as expected.
Any other clues or is it time to call in an expert or see who has offers on washing machines?!?
Have you used the washing machine plugged into the RCD and does it trip? If it doesn’t it’s hard to see how the washing machine could possibly be earthed if it doesn’t trip a sensitive RCD. Check continuity from the earth pin on the plug to the earth on the heating element.
Well the problem seems to have gone away, not reassuring me as somethings obviously not right but thank you for your help anyway Andy!