fffcj Tiny little 'shock' and earth question .

[fffcj]

My Engl Fireball 60Watt amp and I are living in Spain . When I touched
the front panel , I got a very very small shock on a finger which had
recently been cut . Nothing was detectable with any of my other dry
fingers .I voltage tested between ground at the wall socket and the
amp , ac and dc . Nothing at all . Then , set on AC , I happened to
be holding one of the probes , with the other attached to the wall
point ground . 2 volts ac registered . I'm stumped . I don't appear to
be attached to anything else !
Where is this small voltage coming from ?
Do I need to worry about the earthing in this humble Spanish cottage ?
Are little 'changes' like this normal , and quite safe ?

 

[Sjouke Burry]

fffcj wrote:

My Engl Fireball 60Watt amp and I are living in Spain . When I touched
the front panel , I got a very very small shock on a finger which had
recently been cut . Nothing was detectable with any of my other dry
fingers .I voltage tested between ground at the wall socket and the
amp , ac and dc . Nothing at all . Then , set on AC , I happened to
be holding one of the probes , with the other attached to the wall
point ground . 2 volts ac registered . I'm stumped . I don't appear to
be attached to anything else !
Where is this small voltage coming from ?
Do I need to worry about the earthing in this humble Spanish cottage ?
Are little 'changes' like this normal , and quite safe ?

You form a capacitive divider.
There is say .2 picofarad between you and an isolated
wire carrying 240 volts.
Your capacity is about 20 picofarad, referred to ground..
that means you carry about 1/100 th of the mains voltage,
or about 2 volts.
At virtually no current.
Everything is as it should be.
This is also the reason you hear hum from the speaker, when you
touch an audio iinput.