29 Jan
2024
29 Jan
'24
5:56 p.m.
On Jan 29, 2024, at 8:47 PM, Jonathan Chapman via
cctalk <cctalk(a)classiccmp.org> wrote:
Thanks for the confirmation. And also a good reminder that static electricity is one way
to charge capacitors, at least ones with good dielectrics. After all, the famous Leyden
jar is nothing more than a capacitor charged by static electricity, and it can certainly
hand out substantial shocks.
paul
This apparently is true of some capacitors as
well, I'm not sure which types.
It is true of all capacitors (CRTs are intentional capacitors, after all) designed for
and subjected to sufficiently high voltage. It's referred to as dielectric absorption,
and is why HV caps ship from the factory with the leads shorted.
I have a 4.7 uF tens-of-kV capacitor in the shop for reasons. The shorting jumper got
knocked off once while moving stuff past it, and I noticed it the next day. By that point,
it had accumulated enough charge to register over 200V on a Simpson 260 VOM (not a high
impedance meter). I don't know if that was accumulated static charge or from
dielectric absorption.
Thanks,
Jonathan