Pyro fuse blew in Powerwall in garage?

[kairojya]

I would appreciate feedback from other owners that had a related incident, or others with systems in their garage that have better monitoring than me. I don't think smoke detectors work well in a garage even without any ICE usage, especially in humid climates. I don't think a rate of temperature rise detector would have detected this incident.

I had what is being referred to as a 'thermal event' with my system today. Given what little understanding I have of these systems, I wonder if a pyro fuse blew. In one of my Powerwalls I can see debris through the side cover near the top where the fan is. The other Powerwall looks clean and brand new by comparison. This Powerwall has a strong electrical burning smell from the top of both side panels. There is no obvious damage on the exterior of my Powerwalls, inverter, or gateway. Nothing obvious inside my inverter.





I happened to go into my garage this afternoon and there was a small amount of smoke and a strong electrical fire/burning smell. At the time I had 2 Model 3's (82 kWh packs) at 60%~ state of charge and 2 Powerwalls fully charged in the garage. It didn't seem like there was an active fire so I moved the cars out and away from the home as fast as I could safely do so.



Then I powered down my solar/Powerwall system via the A/C disconnect, and started checking everything. Oddly my Powerwall+ 50A breaker was in an intermediary position:



My system seemed to be operating fine and was looking like a record solar production day. When I went to the Support page in the app I noticed that the system had already generated a service request:



It turned out that several days ago one of my Powerwalls detected a fault. After 24 hours if a fault persists, the system will generate a support request automatically. I never received a notification about it in the app, via email, via text/voice message. I check the app often every day too. I first learned of it when I went into the Support section on the energy side of the app after my incident today. I called the energy customer support number that I had saved in my phone from previous issues and explained what happened. I'm using a baby monitor to keep an eye on my powered down system as I wait for Tesla to work my high priority ticket.

 

[BGbreeder]

Based on your breaker, it looks like your Powerwall + had an unplanned "overload".

It would also seem as if your safety systems worked as intended. I think shutting the system down and flipping the breakers all the way to "OFF" is definitely prudent. (Nice touch to use a baby monitor to keep a watch on the system.)

Good luck and keep us posted please!

All the best,

BG

 

[Vines]

Looks like there was some hardware failure and the safety systems worked as intended.

Let us know what the resolution is. I suspect they will RMA this unit when they can get a crew out.

 

[Matt-FL]

Curious to see the resolution process and timeline for future reference.

 

[taphil]

Here’s my timeline

Powerwall died? DC Stage Fault

I was at home and heard a a few loud pops but didn't know where they were coming from, thought maybe outside. Later on I look at the Tesla app and it says "Powerwall Disconnected, Breaker or Disconnect Open." Went out to the Gateway, and indeed one 30A breaker for one Powerwall tripped. I...

teslamotorsclub.com

 

[kairojya]

Based on your breaker, it looks like your Powerwall + had an unplanned "overload".

It would also seem as if your safety systems worked as intended. I think shutting the system down and flipping the breakers all the way to "OFF" is definitely prudent. (Nice touch to use a baby monitor to keep a watch on the system.)

Good luck and keep us posted please!

All the best,

BG

Looks like there was some hardware failure and the safety systems worked as intended.

Let us know what the resolution is. I suspect they will RMA this unit when they can get a crew out.

Curious to see the resolution process and timeline for future reference.

Thank you all for the feedback, I will follow up. I did ultimately flip the 2 Powerwall breakers off in addition to the toggle switches on the side panels of both Powerwalls.

The techs assure me that the failsafes worked. Something appears to have blown in my Powerwall+ unit as there is soot/debris in that space at the top where the radiator, fan, and some low voltage wiring harnesses are.

Here’s my timeline

Powerwall died? DC Stage Fault

I was at home and heard a a few loud pops but didn't know where they were coming from, thought maybe outside. Later on I look at the Tesla app and it says "Powerwall Disconnected, Breaker or Disconnect Open." Went out to the Gateway, and indeed one 30A breaker for one Powerwall tripped. I...

teslamotorsclub.com

Thank you for sharing, I checked through some of your thread but want to read through it thoroughly later today and follow up if I have any questions/comments.

 

[kairojya]

Update
My Powerwall+ (just the PW, not the inverter) was replaced today and my system is back online. I am pleasantly surprised by Tesla’s response time. My system was back online with a Powerwall replaced within 22 hours of me calling in to report the “thermal event”.

From what I was told, an engineer(s) that remotely reviewed the case said the AC-DC converter is what burned / blew up. The only thing notable that the onsite crew found, that I hadn’t already saw and reported yesterday, was when they pulled the Powerwall+ off the wall and saw a burn mark on the back side of the unit. There were on site for several hours today, and I had to step out during the time that they pulled the unit off the wall. I didn’t get to see it myself, they told me about it when I returned. Another truck came to bring the new unit and they had already left with the bad one by that time.

I’m not sure how comfortable to feel about this. I’m happy that Tesla responded quickly. It looks like I won’t be able to find out what failed or what the root cause was with my Powerwall+. I’m unhappy that the unit detected a fault several days prior and never alerted me of it. It created a support request that was only visible if I had gone into the Support section in the app. Since I was never alerted to an issue, I had no reason to ever go into the Support section until the thermal event took place. Had I know there was a serious fault, I could have turned the system off several days prior to the thermal event instead of waiting for Tesla to process the presumably lower urgency automated support request. I think once I called in and described the thermal event, that trigged a higher priority, which I can’t think of a reason why it shouldn’t have.

It should be noted that I had one of the early Powerwall+ units. I was the 2nd install in my area after they became available. I assume Tesla has made many changes since then like they do on the automotive side, and hope that I won’t ever have a ‘thermal event’ ever again.

The API reports a nominal full capacity of 15.0 kWh. My original Powerwall+ reported 14.1 kWh about 45 days after install.


@taphil just read through your thread, you had a much more frustrating experience than me. Sorry to hear about it. I heard similar pops/bangs like in your video. There were 2+ of them, and I only ended up having 1 breaker trip. This was all after whatever burned or blew up that caused the smoke and smell.

 

[BGbreeder]

That's great news! I'm glad that you got it repaired/replaced so quickly.

I wonder if there are/were some components in the early versions that were at / close to the redline, so to speak.

Frankly, I'm impressed that Powerwalls work so well. Perhaps I am easily impressed.

All the best,

BG