Enphase system starts producing only at start of day

[sowbug]

I recently installed a DIY Enphase system. It has IQ8 microinverters and a Combiner 4, with 335W 60-cell panels. It's working fine with one strange exception. If I turn off the system mid-day, for example by throwing the rapid-disconnect switch, then after I turn it back on, the system won't resume producing power until the next day. The Envoy's local webpage reports all 16 detected and all 16 communicating, but zero producing power. If I leave the system alone, then once the sun comes back up the next day, it'll start happily producing.

I see online that at least two other people have experienced this problem, but the feedback didn't lead to a solution. One person did try an experiment disconnecting one microinverter from the PV panel and then reconnecting, and sure enough, it began producing power again. So it seems that if the IQ8s lose AC power mid-day, then they lose their marbles and need zero DC voltage to find them again.

I'd rather not have to throw a tarp over my panels every time their AC power is interrupted. Anyone have an idea what's going on? I will report the issue to my system manager and to Enphase, but I thought I'd ask here for community advice.

[Ampster]

Is the problem a reporting issue. There have been delays with Enphase reporting. When the system comes back the next day does previous day still show gap in production?

[sowbug]

I don't think it is a reporting issue. It first happened on September 14, and then again yesterday on September 20, and the month view of Energy on the Enphase website still shows near-zero production on both those days. Each day after that looks normal, which refutes one explanation that the energy is being produced but mistakenly lumped into the next day. It's also been long enough that any backlog from September 14 should have shown up by now.

I also checked my PG&E smart-meter usage graphs. It's noisy, but if I squint I see higher usage on the days when the panels weren't helping out.

While it's happening, the Envoy's production light is off -- not green, not amber/red, not blinking -- and the local Envoy web page reports zero production.

[solardreamer]

What events do you see in Envoy?

[sowbug]

If that's an Enlighten Manager feature, I don't have it. I ran out of money well before this project got to where it is now.

Incidentally, back in 2014 I had an Enphase system on another house, and I remember being able to see a lot of detail on the website -- geek stuff. I was mildly excited to get back into the Enphase world with my current home, but it seems that in the intervening nine years, they've made the website look nicer while moving features to a higher price tier. I wish I'd known this before deciding to buy Enphase again (not that there's a lot of competition).

[solardreamer]

If that's an Enlighten Manager feature, I don't have it. I ran out of money well before this project got to where it is now.

No need for Enlighten. Just local access to the iQ Envoy/Gateway that should be in your Combiner. You need to access the installer view (with installer login) on the Envoy to get the detail info.

[sowbug]

I'm drinking from a firehose at the moment. I clicked "Installer Login" and was taken immediately to a 401 error page. I did a bit of research, found the old Android app that is supposed to generate the token for the combiner. That didn't install on my modern Android phone, and it appears that it wouldn't have worked anyway because that login link seems to have been killed with a recent firmware update. Which means that I probably need a real Enphase installer login to see what you're describing (even though it's my own hardware that I purchased!).

I did once sign up for an installer account, but the account doesn't have any affiliation with my combiner, so when I try signing in with that account, I get bounced out with a "Sorry, you are not authorized to view that page." I tried asking Enphase support to change my main account to be an installer account, and that costs $250, so I said no. I also tried adding my installer account to the authorized users/companies for my site, and that was rejected.

TL;DR: I don't think I'm going to be able to see anything useful that would allow me to diagnose the issue myself.

[solardreamer]

Enphase offers free online installer training and certification. Perhaps once you are certified you can get free installer access.

[sowbug]

Good tip! But I'm not sure how far down this rabbit hole I want to go.

Meanwhile, I've filed a ticket with my system manager. They're first going to see whether there's a firmware update, and then check with Enphase about known issues. Meanwhile, thanks for helping me talk through the problem. I'll update the thread if I learn anything.

[SamirD]

Curious to see if you've found a solution. It's a weird problem and hence my curiosity since I also have an enphase system (but with older M series microinverters).

[sowbug]

I'm active on the Enphase support thread I linked to earlier. The most recent reply there says that Enphase knows about the issue as of July 27, 2023, and is still working on a fix. I have not personally heard anything further from anyone, and I haven't tried to see whether the problem has gone away on my system (which reports that it is running firmware D7.3.466).

Based on experimentation other owners have done, I believe that if you had a very, very large blanket and covered your panels completely for a few minutes after disconnecting the system from the grid, then removed the blanket and turned everything back on, then power production would resume. The key is lowering both AC and DC voltage to the microinverters to a point where they reboot themselves. Obviously such a workaround would be impractical and potentially dangerous. It's much safer to wait for the blanket of nightfall, even if it forfeits the partial day's worth of production.

[SamirD]

Thank you for the update! Sound like it's something a firmware update to the microinverters will solve. Hope they get that out sooner than later because there's a lot of installs with the iq8 that are probably running into the same issue, but they don't know since they've never shut it off mid-day.

[bcroe]

I recently installed a DIY Enphase system. It has IQ8 microinverters and a Combiner 4, with 335W 60-cell panels. It's working fine with one strange exception. If I turn off the system mid-day, for example by throwing the rapid-disconnect switch, then after I turn it back on, the system won't resume producing power until the next day. The Envoy's local webpage reports all 16 detected and all 16 communicating, but zero producing power. If I leave the system alone, then once the sun comes back up the next day, it'll start happily producing.

When the sun rises, panel voltage will gradually rise until the inverter can
operate, limiting voltage to MPPT point. But when you apply AC power
during the day, the inverter is already hit by open circuit peak voltage, and
maximum current capability. If that voltage is within design limits, then the
problem might be with the startup software. good luck, Bruce Roe

[SamirD]

When the sun rises, panel voltage will gradually rise until the inverter can
operate, limiting voltage to MPPT point. But when you apply AC power
during the day, the inverter is already hit by open circuit peak voltage, and
maximum current capability. If that voltage is within design limits, then the
problem might be with the startup software. good luck, Bruce Roe

Thank you for the additional insights Bruce!

[Rade]

We had an issue with on of our Generac PVLinks here. It was catching intermittent shadows off a tree during the mornings in July and August. The rapid "Full power / No power" cycle caused the inverter to place the array into mumble mode for the rest of the day. It would recover for the next morning, then hit that time of morning again to go offline. They changed a parameter on the inverter for that array (discussed in other threads here) and that seems to have solved the issue.