Inverter Shutting Down

[lucassaugen]

I've got a ticket in with Tesla but the first person I talked to didn't seem to know if this was even an issue. Waiting to hear back.

Whenever there's a drop in sunlight the inverter goes into night mode and stays there for like 30 minutes.

So, if a stray cloud passes in front of the sun for 5 seconds and then moves on. My inverter shuts down for 30 minutes and then comes back like nothing happened.

So, yesterday was very sunny and late in the afternoon we had some high faint clouds start to roll in.

I have a Delta M4 inverter and it was the first time our installers had installed it. Had to come back a couple of times to fix the 2.7kWh cap but they took care of that without me asking.

 

[gpez]

Welcome!

I think some more details would be super helpful.

- Could you include the other graphs in your screen shot? Home, Powerwall, Solar, and Grid?
- What mode is your Powerwall in? A screen shot of the settings page would work.
- Did you verify by chance that your inverters are actually shutting down (as opposed to this simply being a data collection and graphing issue)?
- Is your inverter giving you any error or status messages when this happens?
- Expanding on that a bit further you said they go in to "night mode". Is that an actual mode or just the way you're describing the fact that they're not producing any more?
- Any other odd behavior you've noticed? Could either be about your solar setup or devices around your house during these production dips.

 

[lucassaugen]

- Could you include the other graphs in your screen shot? Home, Powerwall, Solar, and Grid?
- What mode is your Powerwall in? A screen shot of the settings page would work.
- Did you verify by chance that your inverters are actually shutting down (as opposed to this simply being a data collection and graphing issue)?
- Is your inverter giving you any error or status messages when this happens?
- Expanding on that a bit further you said they go in to "night mode". Is that an actual mode or just the way you're describing the fact that they're not producing any more?
- Any other odd behavior you've noticed? Could either be about your solar setup or devices around your house during these production dips.

I'll include another screenshot at the bottom of this post, but I've seen no correlation between anything except for a drop in sunlight on the panels. If I was to walk in front of the panels my own shadow would cause the inverter to go into night mode.

Powerwall is currently in cost savings mode but I've tried all modes and nothing changes.

The Delta M4 Inverter doesn't have a display. The only way to see the error log is with a bluetooth app on an android phone. I am able to use the M Professional app on my iOS phone and see some data but not the log. There are some flashing lights on the front side of the inverter. Those lights tell me it goes into 'night mode' according to the instruction manual.

With this same app I am able to confirm it's not a reporting error. The graphs from the inverter matches the Tesla App.

The last thing I notice in the iOS app is that the inverter isn't even checking for voltage during these outage times. I think this is because it's gone into it's night mode which I assume is some sort of power saving mode for the evening where it only wakes up to check for current every once in a while.

Nothing else around the house seems odd.

I'm also including a screenshot from yesterday when there were no clouds in the sky. You will see two times towards the end of the day when the inverter shutsdown. This happens every day around that time because a shadow from a tree moves over one of the panels. 30 minutes later that shadow is still on the panel but the inverter wakes back up and starts to produce again but lower production because of the shadow. Another tree shadow moves on to the panel later and that's the second drop.

 

[gpez]

Totally sounds like an issue with your inverter (maybe panels?) and with the additional info you provided it doesn't strike me as a Powerwall issue.

Are you able to get the installer out to look at it? Perhaps there's a firmware bug or configuration setting that is screwy. The M4 manual states night mode: "Grid is connected, but the inverter is unable to feed in grid because PV voltage is too low." http://www.deltaww.com/filecenter/Products/Download/05/0505/user Manual of M series_20180123-00.pdf page 42. One panel being shaded shouldn't cause the inverter to drop off. If your PVs are operating normally then my bet is on the inverter.

 

[mrizzo123]

OMG! I have the EXACT SAME ISSUE. I just had these installed. I have a 15KW system with two Delta M8 inverters. I noticed the same sensitivity to slight change in light, even small clouds cause the system to go in to some sort of reset. I used the same tool and noticed when I caught the error it was showing a PV Undervolt. What is interesting is sometimes the Delta app shows no voltage on some of the strings when there is full sun. I am no electrical engineer but my feeling is that this inverter is not handling the adjustment of MPPT when there is a slight fluctuation of output power, dragging down the voltage and tripping an arc fault system or something.

I have complained to the installer who agreed that this should not be happening. He had me call Tesla tech support. After a week or so they seemed to note some issues, however, they told me that I am on the latest Firmware. I have been waiting almost 2 weeks for a tech to come out to my house. Sigh..

Tesla either fixes this thing or I want another inverter brand, these things seem to be crap or they are not installing them correctly. I have a basic 200W panel with a Victron Energy MPPT charge controller. That thing can charge almost in bright moonlight. I would hope this fancy setup I got from Tesla would be better.

I have also noted that around 4:15pm the output just stops, regardless of sun. Sure I am not at the apex, but I mean I should be getting 3-4KW out of the damn thing in the summer.

Thanks to gpez, who has been helping me connect my powewall system to my home automation stuff. He pointed this thread out. At least I do not feel alone...

 

[charlesj]

That should not happen. I have that on my app at times, yet on the Enphase home page, my inverter company, There are no such zero production. Other days it follows production very well, clear or clouds passage.
Could it be the sensors or the app?
I have noticed a few huge difference between the apple app and windows app of the same day. Crazy. Same data, different outcomes.

 

[mrizzo123]

That should not happen. I have that on my app at times, yet on the Enphase home page, my inverter company, There are no such zero production. Other days it follows production very well, clear or clouds passage.
Could it be the sensors or the app?
I have noticed a few huge difference between the apple app and windows app of the same day. Crazy. Same data, different outcomes.

I have used the same app as the OP has used and confirmed that there is no power being made, so I do not think it is just a lag with the energy gateway. You can also tell that the inverter is in some sort of reset process by the behavior of the status lights. It is definitely freaking out for some reason and not making power for large chunks of time.

 

[charlesj]

Well, I have also seen this issue with house power usage on the app, periods and at times for hours on end, the house is not using power , zero.
That is an impossibility as the house is powered during those times. That is not an inverter issue and my Enphase inverters don't have those issues, certainly not all 17 of them .
So, I don't know what is going on. Maybe I should have been calling tech support every time it happens?

 

[lucassaugen]

Following up on my original post.

I did get a tech out here and they were already aware of the problem. It has something to do with the MCC(?)s on each panel that communicate to the inverter. They are sensing the drop in sunlight and telling the inverter to shutdown for safety. This is a firmware issue from Delta that they need to fix. I'm actually surprised Tesla is still installing these inverters without a fix in place.

The shutdown happens a lot out here on the coast where we have fog that rolls in.

This was many months ago that the tech was out here and there still isn't a firmware update to fix it. I'm not sure what we need to do to get this firmware fixed.

 

[charlesj]

While you have a solar shut down, I experience this with home consumption and shorter periods of solar dropping to zero briefly. Way different inverters so that is not my issue.
Here is a screenshot of Aug 9 home consumption.
Zero consumption for a very long time. Of course house was powered as usual. Finally passed this on to techs as well.

 

[brigs]

I made an account just to post here. I have the exact same issue, and it's a problem with the inverter whenever shade hits ANY of the panels. We have a tiny little chimney that throws a small bit of shade on the bottom corner of one of our panels and it shuts the entire system off. Tesla says this is a known problem and that Delta is working on a firmware update to solve it. Granted, if you guys had this problem back in April I wonder how long it's going to take to fix it...

 

[charlesj]

I made an account just to post here. I have the exact same issue, and it's a problem with the inverter whenever shade hits ANY of the panels. We have a tiny little chimney that throws a small bit of shade on the bottom corner of one of our panels and it shuts the entire system off. Tesla says this is a known problem and that Delta is working on a firmware update to solve it. Granted, if you guys had this problem back in April I wonder how long it's going to take to fix it...

I am not sure whom you are responding to.
My picture is the house not using any energy that cannot be.
Finally this issue was solved yesterday for me. One was a current sensor in subpanel was not a real powerline sensor sending info through power line but through an antenna that was inside the metal subpanel.

 

[lucassaugen]

He was responding to me, the original poster.

I didn't post it here but I did learn about the firmware issue when a tech came out. He did a short term fix that did solve the problem for now. Still waiting on that firmware though. I hear there was a beta in the wild being tested but it wasn't fixing the problem. I can't believe Tesla is still installing this combo with the known issues.

 

[brigs]

What was the short-term fix? Do you have any info on it?

 

[lucassaugen]

The issue is between the inverter and the MCIs. If you remove one of those two things from the situation the issue goes away.

 

[Odobo]

Just found this post after trying to search for this problem.

Just wanted to add that there are multiple apps you can download on a android by a developer call HDC SPA Team. They developed the M Professional that if you search Delta M series inverter on google, you will find link that mentioned it. But they also developed a couple more apps that are basically the same thing but have a little bit more functions. One of them call Trinahomr actually pull the error logs and I can see whenever the solar stop working, there was a arc fault and reported voltage of 470 V in my case.

There is alsoa m-tool app that you can find on IOS devices, on there you will find a ARC setting that you can enable/disable it. Mine was enabled and instead of 15 to 30 min stoppage, it will have a arc fault error every time a cloud fly over and stop for like 5 to 15 mins..... It also happens much more frequent with it enabled. When I disable it, I see similar stoppage as OP's graph....

 

[lucassaugen]

Oh nice! I downloaded the Trinahome and was able to see the logs. Thanks.

 

[giac]

I have exactly the same problem. With a M8 , I have 3 PV arrays. One of the arrays just stops working suddenly at around noon.

Has Tesla solved this issue for anyone? I'd rather not play around with the inverter myself...

 

[MorrisonHiker]

I have exactly the same problem. With a M8 , I have 3 PV arrays. One of the arrays just stops working suddenly at around noon.

Has Tesla solved this issue for anyone? I'd rather not play around with the inverter myself...

We have 4 inverters and noticed one of them started shutting down on warm days last summer. Tesla came out to check on things but it hasn't been over 75F/24C in months, so we don't know yet if the issue has been fixed. If it starts happening again this spring, we'll be calling right away to report it.

 

[ejcj]

Hi there, I am experiencing this issue too. Has there been a resolution? Even small clouds throw the M4 inverted into it's reboot cycle.