Tip/Warning if you have more than one Powerwall

[Yonki]

Just had a Solar + 3 Powerwall system installed. Have been running off-grid while waiting for PTO. App shows 3 Powerwalls with a state of charge somewhere between 0% and 100%. Walls charge up to 100% during the day; house runs off Powerwalls when there’s no solar production.

After a week or two I got the feeling that the Powerwalls were discharging too quickly. As an example with nice round numbers, let’s say I was running off the Powerwalls for 13.5 hours between sunset and sunrise, and my house used an average of 1kW. So I would have drawn about 13.5kWh from the Powerwalls between when the panels stopped producing and when they restarted.

Since each Powerwall has 13.5kWh of energy, I basically used 1 Powerwall worth of energy overnight. But my app said I was at 50%, not 67% (as you’d expect with 3 Powerwalls). I did similar measurements and calculations over several days and concluded that my system was behaving as if I only had 2 Powerwalls, not 3 (even though the app always said I had 3). All 3 Powerwalls were on and glowing green on the sides. I also reset the Gateway and the Powerwalls multiple times during my testing to make sure that didn’t solve the problem.

I eventually got through to Tesla and had them run a diagnostic. Initially they saw nothing - everything looked fine. I asked them to look again and after more testing, they said something like “oh…it looks like one of your Powerwalls is in permanent standby.” So they confirmed that I had a Powerwall that wasn’t working correctly and opened a “Tier 2 ticket” or some such thing that hopefully someday will lead to the problem being fixed.

So my warning to everyone with multiple Powerwalls is:

You could have a completely non-functional Powerwall and the problem will not show up in your app and Tesla might never notice.​

So I recommend you do a sanity check (compare kWh usage vs % drained) periodically to make sure you have all the energy storage you paid for.

There were two other clues that I had a bad Powerwall. The first is that when I turned my Powerwalls off and on with the switch on the side, you could hear relays clicking inside 2 of them, but one was silent.

The second clue is that (labeling my 3 Powerwalls A, B, and C), I could turn off A and B, and C would continue to power the house. I could turn off A and C, and B would continue to power the house. But if I turned off B and C, there was no power.

 

[zƬesla]

Guessing you may also be able to check the status through the TEG Powerwall API by browsing to https://TEG/api/powerwalls. If you are not already signed into the TEG, visit https://TEG/ first to sign in. Replace TEG in the URL with your local TEG IP address. (TEG = Tesla Energy Gateway)

 

[BGbreeder]

Just had a Solar + 3 Powerwall system installed. Have been running off-grid while waiting for PTO. App shows 3 Powerwalls with a state of charge somewhere between 0% and 100%. Walls charge up to 100% during the day; house runs off Powerwalls when there’s no solar production.

After a week or two I got the feeling that the Powerwalls were discharging too quickly. As an example with nice round numbers, let’s say I was running off the Powerwalls for 13.5 hours between sunset and sunrise, and my house used an average of 1kW. So I would have drawn about 13.5kWh from the Powerwalls between when the panels stopped producing and when they restarted.

Since each Powerwall has 13.5kWh of energy, I basically used 1 Powerwall worth of energy overnight. But my app said I was at 50%, not 67% (as you’d expect with 3 Powerwalls). I did similar measurements and calculations over several days and concluded that my system was behaving as if I only had 2 Powerwalls, not 3 (even though the app always said I had 3). All 3 Powerwalls were on and glowing green on the sides. I also reset the Gateway and the Powerwalls multiple times during my testing to make sure that didn’t solve the problem.

I eventually got through to Tesla and had them run a diagnostic. Initially they saw nothing - everything looked fine. I asked them to look again and after more testing, they said something like “oh…it looks like one of your Powerwalls is in permanent standby.” So they confirmed that I had a Powerwall that wasn’t working correctly and opened a “Tier 2 ticket” or some such thing that hopefully someday will lead to the problem being fixed.

So my warning to everyone with multiple Powerwalls is:

You could have a completely non-functional Powerwall and the problem will not show up in your app and Tesla might never notice.​

So I recommend you do a sanity check (compare kWh usage vs % drained) periodically to make sure you have all the energy storage you paid for.

There were two other clues that I had a bad Powerwall. The first is that when I turned my Powerwalls off and on with the switch on the side, you could hear relays clicking inside 2 of them, but one was silent.

The second clue is that (labeling my 3 Powerwalls A, B, and C), I could turn off A and B, and C would continue to power the house. I could turn off A and C, and B would continue to power the house. But if I turned off B and C, there was no power.

Thanks for the tip. I will double check the math on the discharges.

I am deep in the "well, the switch doesn't do anything" with Tesla at the moment. They have run diagnostics and say that it is "OK", but don't have a response for "well, the switch doesn't do anything".

More when I know it...

All the best,

BG

 

[Yonki]

Guessing you may also be able to check the status through the TEG Powerwall API by browsing to https://TEG/api/powerwalls. If you are not already signed into the TEG, visit https://TEG/ first to sign in. Replace TEG in the URL with your local TEG IP address. (TEG = Tesla Energy Gateway)

I’ve been meaning to try out that API, will try this weekend. Thanks.

 

[zƬesla]

I’ve been meaning to try out that API, will try this weekend. Thanks.

Take a look at the docs. I may have the wrong URL.

GitHub - vloschiavo/powerwall2: Tesla Powerwall 2 - Local Gateway API documentation

Tesla Powerwall 2 - Local Gateway API documentation - vloschiavo/powerwall2

github.com

 

[Flyguy]

Thanks for the FYI. Were all three green side mounted strips pulsating when the Powerwalls were discharging?

 

[miimura]

When my Powerwalls were first installed, I put them in backup mode to charge them. It only ever reached 54%. It turns out that the breaker to one Powerwall was off. Turning it on allowed the system to reach 100%.

 

[Yonki]

Thanks for the FYI. Were all three green side mounted strips pulsating when the Powerwalls were discharging?

Good question! The two good Powerwalls are pulsating but the bad one is just solid green. Another tell!

 

[genobi]

I'm in a similar boat...

I do extensive logging of the power status using the /api/meters/aggregates endpoint and store it (I query every 5 seconds, so far 33GB of JSON data!). Looking at my dashboard I noticed the charge curve was more "boxy" than it should be. Subsequent investigations shows it skips ~45% of the battery charge (while charging/discharging it might go from 44% to 90% within a single 5 second polling interval). I called the installer, who is also the ONLY group who can provide the warranty service outside of Tesla, and if I didn't have gobs of data to show, I doubt they would take me seriously. They reached out to Tesla who asked me for some info (specifically the info I provided the installer already...) and I provided them lots, including very specific time stamps and payloads. 12 days later... all I know is that "they found some alerts" and are continuing to investigate.

Hopefully something is done. Its actually infuriating to realize there is a whole alerting mechanism within the gateway that no one is looking at (tesla nor the installer), doesn't show in the Tesla App and we have zero access to as owners. I asked if I can get access, even via API. If I stumble across something, I will post the endpoint here and propose a commit to the vloschiavo/powerwall2 repo

-Justin

 

[slcasner]

Hopefully something is done. Its actually infuriating to realize there is a whole alerting mechanism within the gateway that no one is looking at (tesla nor the installer), doesn't show in the Tesla App and we have zero access to as owners. I asked if I can get access, even via API. If I stumble across something, I will post the endpoint here and propose a commit to the vloschiavo/powerwall2 repo

The alerts are accessible through the /api/devices/vitals endpoint that returns binary data in Google's protocol buffers format. See the jasonacox/pypowerwall repo.

 

[genobi]

That is awesome. Thanks.

 

[tedsk]

Same here. One of the two powerwalls I have faulted but no alerts of any kind in the app. Just noticed that my powerwall is discharging way too quickly for the capacity it should have. After calculating actual capacity using consumed kWhs and lost % of SoC I figured out it has less that 50% of its nominal capacity of 27kWh (13.5x2). Diving into the problem and pulling vitals from it I discovered that one of two units is complete toast with bunch of nasty alerts:
"alerts": [
"POD_f030_HW_CMA_UV",
"POD_w024_HW_Fault_Asserted",
"POD_w030_HW_CMA_UV",
"POD_w032_SW_Brick_UV",
"POD_w044_SW_Brick_UV_Warning",
"POD_w058_SW_App_Boot",
"POD_w063_SW_SOC_Imbalance",
"POD_w067_SW_Not_Enough_Energy_Precharge",
"POD_w090_SW_SOC_Imbalance_Limit_Charge",
"POD_w093_SW_Charge_Request",
"POD_w105_SW_EOD"
],
I do not believe that this issue could be just "missed" by Tesla.
IMO they are hiding such problems as faulted batteries deliberately to save themselves money at owners expense.
If I didn't notice that it is discharging too quickly it would have stayed unnoticed for a long time if not for its lifetime.

Such a shame.

 

[CrazyRabbit]

Do these alerts look normal?

 

[CrazyRabbit]

One can also look at energy_discharged, values should be nearly equal.. https://192.168.xxx.xxx/api/system_status

 

[Matt621]

This is a long post, but trust me I think you'll find it worthy of your time.

I too have had issues with multiple Tesla PW. We had 3 installed. When the system went "live" we were not getting the power overnight that we should have. Basically we were running out of energy by 8-9pm each night. I put in a TT to the installers of the system and they said they would look into it but I never heard back from them. I'm not as well versed (yet) as most of you in doing the math, but I knew 3 should be lasting more than 3-4 hours. One other thing I had trouble with was my UPSes in the home. We have 10 computers and almost all are on UPSes. And we frequently have power outages (rural community with not the most reliable grid). But what was happening was when the power would go out, it would take about 1 second for the PW to kick in. But that was too slow for all the UPSes so they'd kick on. However, some of them, the BETTER one, would not kick back off. This was very confusing to me and it was depleting the UPSes when we still had power from the powerwall. Upon some searching I found the issue. The PW/Solar system was kicking the frequency up to 65.5 hz. This cause the better UPSes to sense a problem with the power so they stayed on. I put in a TT with Tesla via the installers and after a few days they confirmed the issues an fixed it. Okay now here is where all this applies to this thread:

Once they fixed that, I now had power all thru the night! Hardly ever touched the grid all night. And before the PW were 'fully charged' by about 10am, but now with all 3 online it took until noon to 1pm to fully charge all 3. I was very happy, but dismayed because If not for my UPSes having issues I might never have noticed it. (Although I would have been complaining that I was running out of electricity at night.)

But wait, there's more! 10 days later I got a notice on my phone about a "maintenance" on my system from Tesla. Okay, were were offline for 8 minutes and back up and running. I have no idea what they "maintained" but whatever. But now we don't have electricity all night like we did before, we are back on the grid again. Looking at the Telsa app and our local power company you can see what I'm talking about.

It could be slightly less production, however if the PW are fully charged by 1-3pm then once we are on them after the sun goes down, they should be good all night unless we decide to cook or run the washing machine, etc. Which we have not been doing. So why were are "slightly" back on the grid at night I don't know. The 10 days from Jun 16 to Jun 26 shows that the 3 PW are enough to cover our usage all during the night. But not anymore. Again I have a TT into Tesla and again I have no response.

So for what it's worth, if you have multiple PW you really need to stop on top of things to make sure you are getting all the power you paid for.

 

[Matt621]

One other thing I meant to mention. During the first part of the graph we had the PW to to 90/10. 90% usage, 10% reserve. And we still were on the grid all during the night. After the first fix, we never got below 25% on the PW. So I changed it to 75% usage/25% reserve. But since the maintenance update I've had to change it to 80% usage/ 20% reserve and I still hit the grid during the night. So we lost 5% reserve capacity as well as still hitting the grid slightly. Also I forgot when we first started (Weeks before what is shown in the attached graph) we were getting PW "offline" msgs almost every morning. I don't know what they did, but we stopped getting those msgs after about a week. But I think that is related to the problem. I think that msg was real and telling us that 1 or more of the 3 PW were really offline. I don't think they actually fixed that problem, I think they just turned off the alert. It was not until the Jun 16th fix that things were really fixed.... for 10 days at least.

 

[power.saver]

Sounds like you are in self powered mode. You need to see how much energy (kWh) is coming out of your PW when they discharge overnight. Three PW have about 40.5kWh energy, and if your reserve is at 25% that means you should be able to draw out about 30kWh after starting with them full. If when you get to 25% less than 30kWh has come out, one may not be working. For example, if you only get 20kWh out when you hit 25% then likely only 2 of the 3 are working. If you only get 10kWh out when you hit 25%, then likely only 1 of the 3 are working. But if you get all 30kWh out when you hit 25% then you may be using more energy at night than you realize.

 

[Matt-FL]

I know several of you have posted screenshots of data collection, figured I'd post a tool (same tool that @CrazyRabbit screenshot earlier) that has helped me stay on top of my powerwall group status.

GitHub - jasonacox/Powerwall-Dashboard: Grafana Dashboard for Tesla Powerwall
Pretty easy install using docker - instructions are easy to follow.

In this dashboard, you get readouts on each powerwall:

• Temperature
• Frequency
• Voltage
• Capacity

Being able to see individual stats for each device will give you the data you need to ensure all the batteries are working as they should.
Far better than the aggregated view in the Tesla app.