madbeanpedals::forum

Projects => General Questions => Topic started by: billstein on November 09, 2013, 07:32:41 AM

Title: Exploding Electroytic
Post by: billstein on November 09, 2013, 07:32:41 AM
Was working on a pedal tonight, plugged it in to test  and had a 100uF electrolytic explode on me! Anybody else ever have this happen?
Title: Re: Exploding Electroytic
Post by: kothoma on November 09, 2013, 07:41:53 AM
Luckily no. Only heard of it. Wrong polarity?
Title: Re: Exploding Electroytic
Post by: billstein on November 09, 2013, 08:24:28 AM
Quote from: kothoma on November 09, 2013, 07:41:53 AM
Luckily no. Only heard of it. Wrong polarity?

That's the first thing I thought of. I checked it and it was right. I looked it over and couldn't find anything wrong so I soldered another one in there and fired it up pointing it away from me just in case. So far everything's good.
This was pretty radical, I think it could cause an injury if the case that blew off hit me. I have no idea where it landed.
Title: Re: Exploding Electroytic
Post by: Gilmourisgod on November 10, 2013, 02:34:30 PM
I wired a power jack wrong, cap blew up in my face as I was leaning right over it, lucky I was wearing glasses.
Title: Re: Exploding Electroytic
Post by: jkokura on November 10, 2013, 05:31:57 PM
Wow! You're fortunate you were wearing glasses. I had one of those blow, and it would seriously damage an eye quite easily.

Jacob
Title: Re: Exploding Electroytic
Post by: mcalaff on November 18, 2013, 05:05:19 PM
Months ago I use a wrong power supply and a electrolytic cap. exploded fortunately inside the pedal. Fortunately the pedal works well with a new cap.

The problem was use an AC adaptor instead of an DC adaptor. A confusion when I bought it.
Title: Re: Exploding Electroytic
Post by: slimtriggers on November 25, 2013, 01:28:37 AM
I've done it.  Scared the crap out of me :D  I had the wrong polarity on my wall wart.  Thought I'd flipped the diode in the power filtering section, so I pulled it out and re-soldered it the other way.  I did this despite verifying the component was correctly installed per the layout and schematic.  The problem was that I wasn't getting any voltage after the diode, so the schematic had to be wrong.  Right?  Luckily I wasn't hurt and all the other components survived.

The moral of the story is to verify that your power supply polarity is correct before beginning to debug your circuit :)
Title: Re: Exploding Electroytic
Post by: pedalman on November 25, 2013, 07:16:37 AM
Had that happen to me last year. Coming to Jesus meeting. Every once in a while we need those reminders. Makes you slow down and double check your work
Title: Re: Exploding Electroytic
Post by: juansolo on November 25, 2013, 06:41:05 PM
Yup, got the polarity wrong. It goes bang in a big way and make a surprising amount of mess.
Title: Re: Exploding Electroytic
Post by: CRBMoA on November 25, 2013, 07:02:12 PM
Quote from: billstein on November 09, 2013, 07:32:41 AM
Was working on a pedal tonight, plugged it in to test  and had a 100uF electrolytic explode on me! Anybody else ever have this happen?

I was working this summer on a DIY P/S that I built 25 years ago. I had overloaded it and blew up a cap. Replaced the cap, but had not identified any other defects caused by my misuse of the P/S.

I used the correct cap, and the polarity was correct. The voltage rating was more than adequate (according to the original build docs).

I powered it up after replacing the cap, and it sounded like a .22 went off in my face, and the metal jacket BARELY missed my face.

I do not have that P/S anymore.
Title: Re: Exploding Electroytic
Post by: jvg13 on November 26, 2013, 12:56:33 AM
.
Title: Re: Exploding Electroytic
Post by: jball85 on November 28, 2013, 07:52:16 PM
my first neovibe build blew up both huge 100ufs at once, I thought that I was gonna have to start over, luckily that wasnt the case. I had the rectifier in backwards (oops).