Voltage earthing through dishwasher casing/door

[Cordless Crazy]

Found out earlier that when I plug my new Bosch dishwasher into a shor

extention lead (one without and earth wire for some reason (afte investigating)) there is some residual voltage running through th casing/metal door lining. Upon touching the door I got a small shoc (bit like and electric fence).

Checked it out and it seems to be of the figure of 50v running betwee the door and the floor i.e. with me acting as an earth!!

Bit more than I expected for residual voltage, as you would get wit most appliances.

Once plugged in to the normal ring main and not with the crappy ex lead (that which is now confined to the shed as spare parts) th residual voltage reading drops to zero (as expected) as the integra earth wire is taking it away.

My question is: does this sound right or is the appliance faulty

-- Cordless Crazy

[Chip]

On Thu, 21 Sep 2006 22:30:06 +0100,it is alleged that Cordless Crazy spake thusly in uk.d-i-y:

With a modern new dishwasher, it's likely to have electronic controls, and thus a mains interference suppressor, which would have capacitors to earth, resulting in a few volts (usually around half mains potential) to 'frame' if the frame isn't earthed.

Usually the leakage is quoted to be at single digit or fractional milliamps from a healthy filter.

[meow2222]

The voltage measured is as much a function of the meter as the appliance, so 50v doesnt tell us much. But a shock form it means its leaking more than it should, so yes somethings wrong. Earthed leaky fixed appliances are commonish and dont seem to contribute to the death figures, even though one would imagine them to be a risk.

NT

[Andy Wade]

I don't agree with that bit. A Class 1 appliance like this could leak up to 0.75 mA, which is more then enough to give a perceptible sensation or tingle, but not a dangerous shock. There's no evidence here of anything being wrong at all, apart from the OP having extension leads lying around with no earth conductor.

[meow2222]

A tingle is not an electric fence like jolt where I come from.

NT

[<me9]

I would expect a tingle enought to wake you up, rather than a shock. If the earth is open circuit to any appliance with switched mode power supplies or motors with brushes I'd expect a mains filter to give about half mains voltage on the earth, and a current to earth of well under 5ma. If it was as high as that it would fail a PAT test and would need investigating.