Eeyore wrote:

Anton Gÿsen wrote:

Serge Auckland wrote:
"Anton Gÿsen" wrote
Eeyore wrote:
Anton Gÿsen wrote:

I have a capacitor rated 0.22 microfarads 250 V AC which came out of a
broken power tool (it was wired in series with the mains supply IIRC) -
would that do?
GOD, you're thick. You shouldn't be allowed ANYWHERE NEAR electricity.
Keep spreading the love, Graham.
What I'm sure Graham meant to say was that the capacitor you have was
designed to go across the mains switch of the power tool as a
suppressor. It would only be in series with the mains supply when the
switch was off, and be shorted out by the switch when switched on. I
would not want to use capacitor rated at only 250 volts on the mains, I
would prefer one rated at least 350v.
Thanks.

And it MUST be 'X-rated'. Don't expect to find it in Maplin.

Only X and Y rated caps are approved for use in mans application.

X for 'across the mains'
Y (pref Y2) for 'mains to ground'

See BSEN 60065.

Why couldn't you have said that in the first place?