EBME Forums Forums Free discussion Out of Hours Exploding multimeter ( cheap and nasty one )

If I understand correctly, CATIII multimeters should be able to withstand 8kV across the inputs - the cheap ones available are not CATIII. Here is what happens to one such multimeter!

Exploding cheapy meter

I wonder what that sparkler-like thing was?

No EBME tech should be using rubbish multimeters anyway.

Something made of ferrite would be my guess.

My own view is somewhat different, Jon. Why not use only cheap test kit, but keep well away from 8 kV (anything kV, in fact)! And ... if you think you are "safe" as long as you're using Big Brand multimeters, then you've literally got a shock coming to you, my friend! Electricity in all its forms needs to be respected!

Interesting how the worktop was blackened and charred BEFORE the meter went titsy. Almost like somebody had been experimenting with frying stuff already. Heck - put kilo-volts with current across most stuff and it'll fry, even kilo-volts with NO current will frazzle CMOS. I expect that if you put a multi-meter in a 1kw microwave oven for five minutes - that's spectacular..... but why would you?

Exactly!

I think that "experiment" is meant to be the VDE testing house, or some such Place of Doom and Great Sadness. Just make sure that you don't send any meters for them to "test"!

I can't help wondering how the Gossen Metrawatt multimeter got on when subjected to the same amount of abuse!

In fairness, and in the interest of balance and suchlike.....
I remember when microwave ovens first appeared, and we put everything we could think of in them just to see what would happen. People said "why would you.....". We said "because we can!".
We thought eggs in their shells would be neat - but they just popped.
Fruit in peel had potential, but was very variable - and messy.
A bar of soap - takes a while but foams into a giant blob.
This had potential - so we went serious.....
Aluminium foil - bright lights and molten metal - and warm microwave units!
Steel Wool - pretty sparkles.
Lightbulbs - glowing colours weirdly before popping.
CD's - pretty fireworks (it was something to do with all the poop on PC mag covers.

I had watched this highly entertaining YouTube guide to choosing a DMM and despite it's "..for beginners" there were points I had not thought about!

http://www.youtube.com/watch?v=gh1n_ELmpFI ( no captions but he speaks very clearly despite his strong Australian accent! )

Dave Jones explains the reasons for not choosing very cheap DMMs, opening a few to point out poor construction practices which ought to put any ebme tech off getting one for work!

He also runs an interesting electronics forum and this thread discusses the DMM video: http://www.eevblog.com/forum/index.php?topic=383.0

Preaching to the converted?

But don't worry, Jon - thieving Pikeys aren't fussy (and I write from sorry experience).

OK, Dave Jones' rants ... er, videos are good ... but ten minutes of that noise is more than enough for me. Thank Goodness I don't work with anyone with rabbit like that!

What brought that remark about? I don't remember any reference to them in Dave Jones' vids or this thread?

I'm sorry Jonathan ... I had thought that the thread was about ways to make your test equipment disappear!