I just got 2 Powerwalls and a Gateway 2 installed last week. I had an existing 22 panel, 5.7 kw solar system with Enphase M215 inverters. The panels are arranged in two strings - one with 14 panels and one string with 8 panels. These two strings feed into a subpanel with two 20/2 circuit breakers and from there are connected into the main panel via a single wire. Initially, after the Powerewalls were installed and the system was powered up, 8 of the panels were not generating power according the the Enphase Enlighten monitoring program. After flipping the breakers in the solar subpanel off and back on again, the 8 panels "woke up" and began generating power. However, I am noticing that in four of the last five days, those same eight panels are going dark for anywhere from 45 minutes to an hour and a half. This happens around noon time when solar production is near its peak, but not at exactly the same time every day. The Powerwall batteries are nowhere near capacity when this happens. Any thoughts on what might be going on?
Powerwall 2 and Enphase M215 problem
- Thread starter Tuolumite
- Start date
The only time the powerwalls would be attempting to turn off the inverters would be if they are at a full charge *and* you are off grid. If you are on grid, then even if the powerwalls are fully charged any excess solar power would just be going back to the grid.
The way the powerwalls turn off the inverters is to raise the frequency (I think the default is 65hz) but, again, they can only raise the frequency if you are off grid. If you are on grid then the powerwalls need to match the grid frequency.
Certainly at first blush it doesn’t seem like the powerwalls would be causing this. Is there any indication from Enphase why they are going offline?
The way the powerwalls turn off the inverters is to raise the frequency (I think the default is 65hz) but, again, they can only raise the frequency if you are off grid. If you are on grid then the powerwalls need to match the grid frequency.
Certainly at first blush it doesn’t seem like the powerwalls would be causing this. Is there any indication from Enphase why they are going offline?
charlesj
Active Member
You need to call Tesla Tech and ask them to lower the frequency of powerwall inverters to 61Hz just above the 215's shut off at 60.5Hz according to Enphase.
I have the same inverters, only 17 panels though, and recently one inverter just decided not to report for a full day and came back the following day. Happened twice now, 3 weeks apart.
Nothing specific from Enphase except the first claimed over voltage that is strange as that would have affected the others equally.
I have the same inverters, only 17 panels though, and recently one inverter just decided not to report for a full day and came back the following day. Happened twice now, 3 weeks apart.
Nothing specific from Enphase except the first claimed over voltage that is strange as that would have affected the others equally.
No indication from Enphase as to why the units are going offline. I did check back several weeks and verified that the outages only began after the Powerwall installation. Very mysterious...
I'll check with Tesla Tech about adjusting the frequency. I'll verify that they have specified the right solar inverter in their setup.
Yes, you would think that any problem with the Powerwall frequency would affect all the inverters, not just those on the one string. And if it was an inverter going bad, you would think it would only affect one panel, not eight.
It’s worth talking to Tesla to adjust the frequency, but as I said above, that’s not your problem. The only time the powerwall frequency will come into play is when you are off grid and the powerwalls are fully charged. When you are on grid the powerwalls need to match the grid frequency or very bad things will happen.
What's the specific error that your inverters are throwing? Usually the inverters or Envoy will tell you exactly what's going on.
Sometimes it's easier to look at the logs of the Envoy itself on the local network, than using the Enlighten website.
You'll want to look at the event log and inventory pages.
My top guess as to the issue:
Comms issues (inverters are still producing, but the envoy can't communicate so they appear offline)
You may need to move the Envoy so it's "closer" to the inverters. Sometimes you'll need to install a noise filter on the subpanel that the Enphase inverters are on if noise is being injected upstream there and have the Envoy wired into the same subpanel as the inverters.
Sometimes it's easier to look at the logs of the Envoy itself on the local network, than using the Enlighten website.
You'll want to look at the event log and inventory pages.
My top guess as to the issue:
Comms issues (inverters are still producing, but the envoy can't communicate so they appear offline)
You may need to move the Envoy so it's "closer" to the inverters. Sometimes you'll need to install a noise filter on the subpanel that the Enphase inverters are on if noise is being injected upstream there and have the Envoy wired into the same subpanel as the inverters.
Your Powerwall installation should include a current transformer monitoring solar output, so what does the Powerwall software show happening to the solar production when the Enlighten software shows the panels dropping out?
If the Powerwall software shows no disruption, the microinverters are still producing, and the problem is a communications problem between the microinverters and the Envoy. [Quite plausibly the Powerall installation degraded that powerline communications channel somewhow.]
While if the Powerwall software shows the same disruption as the Envoy software, then there should be an error message logged by Envoy, you just need to find it. [Unless the same phenomenon is both knocking out production and communications, while seems unlikely.]
Cheers, Wayne
I agree that a frequency problem is a longshot, given that most of the inverters are behaving normally.
Good suggestion, but both the Tesla app and the Enlighten monitoring program are showing a power dropoff at the same time, so I think it's not a communication issue. I haven't found anywhere on the Enlighten site where it is reporting an inverter error. It just shows the power going to zero on the bank of eight panels. Looking at the individual inverter data, I'm not finding anything abnormal. I'll see if I can find the event log on the Envoy.
Both the Powerwall software and the Envoy are showing the same power dropoff. I'll try to find the Envoy error message. I'm not finding any on the Enlighten website.
Perhaps depending on the vintage of Envoy, if you go to the physical Envoy unit it should display its current IP address on the LCD screen. Then if you type that IP address into a web browser on a computer on your local network, you'll get the Envoy's local web page. On the top is a choice called "Events". If you check that log during the no production period, the most recent events should show the reason for the lack of production. If you check the log at a different time, you'll have to scroll back through all the hum-drum events that get logged all the time to find the events related to the drop in production.
At least, that's how my Envoy works.
The most likely reason for the drop in production, given your description, is overvoltage. This happens when the supply voltage at the electrical service from the power company is on the high end of allowable, and the cumulative resistance of the wiring between the electrical service and the microinverters is sufficient that the microinverters would have to exceed their maximum programmed voltage in order to export power. [If you're familiar with the usual notion of voltage drop, then since the microinverters are a supply, the voltage drops from them to the electrical service; and since the power company's voltage is what the microinverters have to match, the effect is a voltage rise at the microinverters relative to the power company.]
This could have been caused by the Powerwall installation either because (a) one of the new connections is actually poorly made and has excess resistance or (b) they just added a bit more wire and a few more connections, which was enough to tip a marginal situation to begin with past the operating boundaries.
In any event, if you're getting overvoltage error messages now, and not before the Powerwall installation, you should get the Powerwall installers to investigate why and fix it.
Cheers, Wayne
At least, that's how my Envoy works.
The most likely reason for the drop in production, given your description, is overvoltage. This happens when the supply voltage at the electrical service from the power company is on the high end of allowable, and the cumulative resistance of the wiring between the electrical service and the microinverters is sufficient that the microinverters would have to exceed their maximum programmed voltage in order to export power. [If you're familiar with the usual notion of voltage drop, then since the microinverters are a supply, the voltage drops from them to the electrical service; and since the power company's voltage is what the microinverters have to match, the effect is a voltage rise at the microinverters relative to the power company.]
This could have been caused by the Powerwall installation either because (a) one of the new connections is actually poorly made and has excess resistance or (b) they just added a bit more wire and a few more connections, which was enough to tip a marginal situation to begin with past the operating boundaries.
In any event, if you're getting overvoltage error messages now, and not before the Powerwall installation, you should get the Powerwall installers to investigate why and fix it.
Cheers, Wayne
OK, I accessed the Envoy event log. All eight inverters are reporting the following three events at the time power production from those inverters shuts down:
at 11:53AM :
AC Frequency Out of Range: Set
AC Voltage Out of Range - Phase 1:Set
Grid Instability: Set
At 12:38 PM, the following event is recorded for 7 or the eight problem inverters:
AC Frequency Out of Range: Clear
At about 12:40 power production from the eight inverters begins again.
At 1:08 PM, seven of the eight problem inverters show:
AC Voltage Out of Range: Phase 1:Clear
AC Frequency Out of Range: Clear
Grid Instability: Clear
At 1:23 PM, one of the eight inverters shows:
AC Voltage Out of Range: Phase 1:Clear
AC Frequency Out of Range: Clear
Grid Instability: Clear
At 1:23 PM, the other seven problem inverters show:
AC Frequency Out of Range: Clear
Grid Instability: Clear
At that point, all inverters are operating at full power again.
You can call Enphase support and ask them, also let them know you have Powerwalls.
There are Grid Profiles just for them.
OK, I don't know enough about the Enphase microinverters to tell you why it is showing both Frequency Out of Range and AC Voltage Out of Range. I would suspect it is a voltage issue.
An independent way to measure the voltage and frequency would be useful here. If you have a Kill-A-Watt then that would work. Otherwise, you can use the Powerwall gateway computer if you can get IP access to it (lookup other threads on how to do that). Then you can type into a web browser:
https://Powerwall_local_IP_address_goes here/api/meters/site
and you have to override any security warnings due to the Powerwall's unsigned certificate. That will give you a response which will include the following fields of interest:
"frequency": 60,
"v_l1n": 121.55999755859375,
"v_l2n": 121.58999633789062,
Once you get a way to measure frequency and voltage, then you want to see if there's a difference between when everything is working and when the 8 microinverters stop outputting. If you verify that there is no difference, and the voltages listed are noticeably higher than 120V, then it is surely an overvoltage problem.
Cheers, Wayne
charlesj
Active Member
Are there enough decimal places in that voltage reading?
No decimal in the frequency? What gives?
Typically you will see this when you lose the grid.
So I suspect a bad or loose electrical connection for this string of 8 microinverters that is probably getting triggered in the middle of the day when solar production is at it's highest.
My recommendation - leave the breaker for that string turned off until you can get all the wiring inspected for the branch.
Just to confirm I read your posts right - the 8 panels that are generating this error are all on the same branch/circuit-breaker, right?
Similar threads
