Magic smoke released, everything still works. Scratching head

2twisty
2twisty Solar Expert Posts: 199 ✭✭✭
This morning, I was awakened to the sound of a capacitor losing its magic smoke. Pop! Hissssssssss.

I jumped up and saw and smelled the smoke lingering in the air, but could not identify the source. All my components still function: the inverter, my battery charger and my charge controller all still appear to be functioning normally.

This has got me really stumped. Any ideas of where I can check? I've examined everything on my power wall that has capacitors in it. I can't find any blown caps and I can't smell it coming from anything. Short of opening up my inverter and charger to inspect physically, I am out of ideas.

I would think that if a cap blew that the component containing it would stop working......

Please advise.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Magic smoke released, everything still works. Scratching head

    Not always DOA--Sometimes they are filter or paralleled capacitors that fail.

    Things to look for... Higher heat/hot components (like paralleled capacitors still working now have higher ripple current). Look at the ends of the capacitors. They may bulge or some may have a "cross" cut in the base (weak spot for venting) that shows cracks in the crosses.

    Wet, shiny, browned spots near capacitor on PC Boards.

    Once the air clears of the smoke/smell... Try smelling air right at each device. Hopefully, you can pick up the smell of the failed component(s) right at the device that failed.

    In general, something else is going to fail--But it could days to months to years... Don't know. Having a workable backup plan (if off grid) with tested/working Genset+AC battery charger+fuel to carry you through until repairs are made.

    Good Luck,
    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • 2twisty
    2twisty Solar Expert Posts: 199 ✭✭✭
    Re: Magic smoke released, everything still works. Scratching head

    Since I planned to do an EQ cycle today anyway, I am charging the batteries up with the generator so that I can EQ with the panels when I have strong sun. I'll wait a bit and try sniffing again.

    If I can't find it, I think I'll open up the inverter. Since it's a cheapy Harbor Fright Chinese piece of fecal matter, I'm gonna bet that's the fail point. It was also physically close to where I saw the smoke. From the location of the smoke, it would almost have to be either the inverter or the charge controller. The battery charger was several feet away from the cloud.

    I removed the cover from the Midnite Classic and I could see nothing wrong with the 4 caps that are visible when the cover is off. No bulging or discoloration.

    I will be replacing this inverter within the next month or so with something better, likely an Outback. So, hopefully, we can get through this without too much trouble.
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: Magic smoke released, everything still works. Scratching head
    2twisty wrote: »
    This morning, I was awakened to the sound of a capacitor losing its magic smoke. Pop! Hissssssssss.

    How do you know (or why do you think) it was a capacitor? Other things can pop and hiss and leave an odor. Maybe you heard and smelled the arcing of a loose connection somewhere.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i