Dyson shocking - minor electric shock by touching the LEDs

[Scott]

I have a Dyson V8 cordless vacuum cleaner. I have noticed I get a very minor electric shock by touching the LEDs when in use. How can this be?

[Andy Bennet]

Static discharge. Either you or the vaccum accumulated charge - more likely the vacuum as just the act of sucking dust can create a charge on the cleaner inside itself. This makes the outside of the cleaner charge up with the opposite polarity via the capacitance effect of the case. An earthy object like yourself then dissipates it via your finger into your body. My workshop vac. case does the same.

[R D S]

Static?

[Steve Walker]

Wait 'til a child has emptied a complete bottle of talc over the carpet! Vaccing that up gave me quite strong static shocks every few seconds from the hose. Dry powders are notorious for static problems.

SteveW

[alan_m]

The vacuum cleaner is plastic and insulated. Dust being sucked up generates static. You are just discharging static electricity.

[newshound]

Yes almost certainly static. But the OP did not report whether it was a single shock, or a continuous "tingle". It is important to recognise the difference, since the former does not matter but the latter does.

I used to get the occasional tingle from a kitchen sink, until I bonded it properly. I've never been able to find where it came from (but it doesn't trip the ELCB).

[Scott]

I think it's each time you touch the LED. I shall experiment further.

Unfortunately, bonding is not practical in a cordless device :-)

[billyorange007]

I once had a car that gave me a quite 0a nstic shock every time I closed a door after stepping out. I got into the habit of closing it with a hand to the window. Probably rubber soled shoes wouldhave helped also

[Dave Plowman (News)]

The once fashionable nylon seat material was notorious for this. And in those days you might have been wearing artificial fibre clothes too - and shoes. Modern fibres seem better in this respect.

[Davey]

When we lived in Michigan, which gets very cold in winter, and so has very dry house interiors, static is a common problem. We used to have a dog who delighted in pushing her nose into the back of our knees, and watching the reaction as the static discharged and our muscles reacted in spasm.

[Brian Gaff]

Static due the the air movement charges up the machine then you earth yourself? Our Henry does this but only a gold leaf electroscope can see the problem. Brian

[Brian Gaff]

My cleaning lady seems particularly prone to this, I suspect she has particularly insulating shoes and then she touches a filing cabinet or a steel bed frame the earthed screws on a light switch and you can actually hear the spark. Brian

[Brian Gaff]

Yes I spill a lot of talk, I'm blind so tend to um miss so to speak. However it does not seem to be just talc. Brian

[Brian Gaff]

If you want tingles, go to underneath a run of electricity pylons with something metal with some insulation. You can clearly feel the 50 hz tingle when you brush up against the metal. I notice it on the bare bits of my white aluminium cane. It also seems to affect the metal guard rails on a bridge across a local stream.

The very end house in the row closest to the pylons seems to change occupants very regularly, and there are stories of people who live there getting headaches and shocks off of things. Brian

[Brian Gaff]

No it would be nice though to find an answer for the sake of my cleaner who gets it a lot both in my bedroom and the bathroom as far as I know no talc in my bedroom but the carpet is the sort with an integral foam back and this is probably breaking down to dust. Brian

[Brian Gaff]

Surely what you need are conductive shoes so it discharges slowly.

Brian

[Scott]

I remember visiting the radio museum in Lahti, Finland. This was in the old transmitter hall under the main antenna. Fluorescent light tubes illuminated without being plugged in. You could hold a steel bar close to the steel reinforcements in the concrete and create an arc. Apparently the visitors were not meant to do this, but I persuaded the guide. She said I was to keep my other hand in my pocket.

[alan_m]

A fine mist of water from the tap can generate static. It once was a problem when cleaning oil tanker tanks.

[newshound]

Yes but is it a continous tingle, or a one-off jolt.

[Johnny B Good]

I've experienced this static discharge effect with various vehicles in the past, and still do on rare occasions with the current vehicle. The trick to avoiding this is to hold onto a metal part of the door before you step out so as to provide a low impedance path to stop the charge building up as you extricate yourself from the vehicle so you remain at the same potential until you're standing outside on the road/pavement.

For further protection against ESD shock, you can push the door closed by pressing on the window glass. ESD isn't an issue when inside the vehicle due to the Faraday Cage effect (the same effect that allows researchers to safely sit inside the top sphere of very large Van der Graff generators whilst they're producing Mega volts of static charge).

Like the researchers who sit inside the top sphere of a Van der Graff generator, they need to discharge the sphere to ground potential before attempting egress. In the case of a vehicle, the problem arises out of static charge building up on your body due to tribo-electric effect which is then magnified by the reduction of capacitive coupling as you extricate yourself without benefit of a low impedance path to the car's metalwork during the process.

Static build up on the car itself is normally drained to ground by the carbon black in the tyres which makes them a leaky insulator that allows such charges to leak away in a matter of seconds. The problem is not so much the car body having a high static charge so much as your own body being charged to a high static potential as you wriggle yourself out of the highly insulated environment of the car's interior.

You could easily have a few kilovolts of charge left on your body by the time you're standing outside about to close the door by contact with a metallic part that's now connected to a large mass very close to ground potential.