Capacitor question

Thank you for interesting information!

Well, at least I know THE single most important thing about electricity that I need to know.

CALL AN ELECTRICIAN! LOL

My analogy was meant merely to mean that those who talk up the danger of capacitors are more often that not people who have no practical experience of the subject, really, but are nonetheless happy to repeat dubious but thrilling Tall Tales of far off danger.

Now you are underplaying the position. Most modern electronics have a power supply that contains a large electrolytic capacitor which (when charged) will typically be at 150v DC in the USA and 330V in places with 240V mains. Needless to say, that is enough to bite you pretty hard. I would expect the OP’s device to have this.

And you can definitely get a shock off an electrolytic capacitor after plugging out. Yes electrolytics leak charge but no so fast that you can’t unplug, open the case, and get a shock. Ask me how I know!

Well, “useless longshorer” is still pretty judgmental and I can see one taking offense to that. It’s interesting, because, like Jasmine, I did think “land-lubber” was a corruption of “land-lover” (“b” ↔ “v” phonemic changes are common in languages) only to discover that “lubber” is a word in its own right which forms the second half of the compound “landlubber.”

It is without question a judgmental term. It is a term seafarers use judgmentally about people who don’t know about matters maritime.

I am a landlubber.

This leads me to what I think is my last question. How long do they hold a charge? I’m thinking it varies with the type of capacitor and the device in which it is being used.

Is the high voltage why CRT TVs were all crackly and full of static electricity if you got near the screen? I remember when I was little (about 8), I moved up close to the screen, and my hair was suddenly plastered to the screen. It scared the heck out of me because I had seen part of the movie Poltergeist, specifically the little blond girl and the TV. LOL

There is no single answer. Most well designed devices should have a bleed resistor across any dangerously high voltage capacitors but some don’t. Capacitors vary tremendously in capacity (ie by several orders of magnitude), and in their leakage current. So how long they take to leak down to a safe voltage cannot be boiled down to a single answer.

Really, if you are going to be playing with this stuff you should (a) understand how to recognise the high voltage capacitors in a given device and (b) know how to discharge them. It’s not hard to learn.

Yes. They typically used the entire CRT envelope as a great big high voltage capacitor.

You mean like this :slightly_smiling_face:

Well thats not a capacitor but a Van-de-Graff generator which is close. And thank you for giving me this idea : I will try to use your idea with my teenage daughter and maybe she will get interested in this stuff :slight_smile:

Or maybe she’ll get really annoyed that her hair is a complete mess. LOL