View Single Post
  #2   Report Post  
Old September 21st 06, 11:37 PM posted to uk.d-i-y
Chip Chip is offline
external usenet poster
First recorded activity by DIYBanter: Jul 2006
Posts: 31
Default Voltage earthing through dishwasher casing/door

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

Found out earlier that when I plug my new Bosch dishwasher into a short
extention lead (one without and earth wire for some reason (after
investigating)) there is some residual voltage running through the
casing/metal door lining. Upon touching the door I got a small shock
(bit like and electric fence).

Checked it out and it seems to be of the figure of 50v running between
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 with
most appliances.

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

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

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.

There is not the slightest indication that nuclear energy will
ever be obtainable. It would mean that the atom would have to
be shattered at will.
- Albert Einstein, 1932