Grid Tie Inverter Fail, Genie escapes.

[dan-tron]

Hi all.  I'm new here but have been watching EEVBlog for over a year.  Something happened today and I thought some here would enjoy it.

One of the two inverters at my parents' house failed today.  They have a grid tie solar system.  One of the units decided to release the blue genie.  Some of it was caught on their surveillance cameras.  (link below) You'll see the smoke wafting from the right side of the screen, followed by mom running out with the phone as she calls the fire dept.  Mom called me next and I walked her through the emergency disconnects to isolate the inverter.  I drove over and arrived on scene after the fire men determined there was no fire.  I opened the unit up as far as I could and took some photos of the damage.  It looks like one of the electrolytic capacitors blew up and hosed everything with electrolyte goo.  I dare not open it further since it is 7 years into a 10 year warranty and I do not want to void it.  So there you have it, a video of the magic genie being released.  Be free!!!

http://youtu.be/eKRxEcsalqs

Oh and the capacitors appear to be Nichicon brand.  I stuck my phone inside and shot a photo looking up into the problem area.  There seems to be a piece of metal above the blown cap.  Not sure if that is the cause or a result of the damage.  Thoughts?

[Richard Crowley]

Certainly do nothing to void the warranty. But if there are two of them, can you do a "differential diagnosis" and compare them to note obvious differences.  Are you SURE that brown liquid came out of the big electrolytic cap?  That doesn't look like what I have seen from other  catastrophic electrolytic failures.  That piece of metal does, indeed look "out of place", but the capacitor doesn't seem particularly vulnerable from that end.  The terminals are on the other end, aren't they?

[dan-tron]

The odd bit of metal is above the top of the cap.  Good idea though, perhaps tomorrow I can go back and take similar pictures looking up into the good unit while fully disconnected from DC and AC of course.

[aargee]

Maybe a transformer has let go, that looks like molten varnish and could explain the metal laminate looking piece on top of the cap.

[TheBay]

Nasty!

That's not from an electrolytic imho.

Good job they don't use PCB's in caps/transformers any more though!

[G7PSK]

That looks like winding varnish to me, also there is too much residue to be from that cap so my guess is the transformer blew up possibly from an inrush of power from the mains. from the mains.

[German_EE]

Agreed, it is varnish. Well done to your mother for doing all the right things before calling you, I hope that she's OK.

[dan-tron]

It had not occured to me that the varnish on the transformer windings would liquify like that.  Interesting.  Today the installer came out and I went over there to meet them.  Its a good thing because I convinced them to replace both Xantrex inverters with SMA's and include monitoring cards.  Probably will happen after Thanksgiving.  But this gives me time to go back and dig into it and see what really happened.

[justanothercanuck]

For firemen, those guys sure walk slow. 

[BillyD]

For firemen, those guys sure walk slow. 

Lol, good point, I was thinking the same. Nor did they look prepared to charge into a wall of flame and smoke!
I'm presuming they were already briefed en route about the condition of the building.

[dan-tron]

Yes.  It seems when you tell them there are no flames, just smoke, and it's electrical, they don't come sirens blazing and fully suited up to jump into a burning building. 

[n45048]

Yes.  It seems when you tell them there are no flames, just smoke, and it's electrical, they don't come sirens blazing and fully suited up to jump into a burning building.

Interesting. In Australia (in my state at least) the fireys respond to *every* job under lights and sirens. Even if it's just fluids on the road from a car crash.

Although they don't bother with breathing apparatus everytime unless there is actual red stuff.

[dan-tron]

Today I had a chance to take apart the failed inverter.  It looks like all that liquid is just from two of the large capacitors actually.  The transformer windings all look to be in perfect condition.  Here's a few pictures of the devastation.  The capacitors that failed are Matsushita Panasonic brand.  All other parts appear to be in good shape but of course that doesn't mean that something else didn't fail, causing cap-splosion. The venting hot electrolyte burned through the plastic shield above the caps (which looked like a piece of metal earlier) and even came out the back of the unit through a hole for the mounting bracket.  Enjoy. 
Thanks.