Exploding cap!

[Robjkmannering]

Bought a cheap Roberts R700 today, plugged into 18v supply and BANG!
A black TCC electrolytic shot its contents into the kitchen wall.
My pregnant wife, who was busy ironing, thought that we had been shot.
I expect this with valve stuff but battery portables?
Has anyone else suffered this and is it just old age or incorrect storage?

Rob

[Joe]

If it was the supply de-coupler it would be straight across the PSU and that would have far more current available than batteries.

I've yet to have one go up on me but was always warned to be careful about connecting them the right way around as they could explode.

At least there's no question as to whether it needs changing or not!

- Joe

[Robjkmannering]

Yes very true, my fault, it was a laptop supply capeable of 4 amps!
Electrolytic had dried up so was just paper/foil mess.
Rob

[Aerodyne]

Years ago I was working on a Telefunken tape recorder. I had the thing vertical on the bench with the base cover removed in order to check voltages. A faint humming began but before I could move there was a bang like a rifle shot and a small electrolytic hit me in the chest with tremendous force, knocking me backward. If I'd been lower I could easily have lost an eye. As it was, I had a fine multicoloured example of a painful and tender bruise that changed hue over a fortnight or so before fading. A new electrolytic worked perfectly. As I recall, it wasn't even at high voltage. Luckily, it is the one occurrence I've experienced so far! I would not have believed it had it not happened to me.
-Tony

[Joe]

I can't quite join this club as there was no bang but I've just connected a 16μF 450V one across the mains, by mistake, and "They don't like it up 'em."

I've got a Bush BP90 on order so was fiddling about with ideas for a PSU. A jet of steam shot out of it more or less instantly and it was bloated and damned hot.

I thought I'd better call it a night after that as I must have been getting tired and it also stunk the workshop out! At least it was only a cheap one.

- Joe

[DODGERN]

It seems as if you are not alone Rob. YouTube has a number of cap explosions although they are pre-meditated. Luckily it wasn't a mains smoother....now they do make a mess!

Roger.

http://www.youtube.com/watch?v=B8gFgIQl2HI

[Jamie-Skinner]

I haven't had any on battery set, I run this from the mains nearly every day?

[tiv48]

yes low voltage electrolytics do go bang years ago a certain satalite reciver was well known for its small electrolytic caps going bang this was of corse caused by a psu fault.battery powered stuff using dry batteries dont tend to suffer be cause of a lack of amps.then again early cannon camcorders used small silver surface mount electrolytics and they would spill there guts over every thing.(more curant from nicad batteries)
rob t