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PV Voltage Being Limited by my new EG4 12000XP

This seems a bit odd for me to understand. In the morning, does the voltage not slowly creep up from 0? Also on some of the warmer days this week, I am unsure this is a problem here in Central FL. I could be wrong, and will test it anyways. I am more thinking the voltage is ramping up to 120v then stopping. It sits right at 120.0v Even during the middle of the day before the reset as well. If it was overloaded somehow, I think it would be safer for it to disconnect or not allow current to flow? I guess a lot of speculation there.
I'm guessing the MPPT algorithm has a bug in it at startup, where it gets stuck, and the fix will be a simple firmware update.

So at https://monitor.eg4electronics.com under Maintenance->Remote Set you don't have Start PV Volt(V) as at here?

Screenshot 2024-11-30 at 5.23.18 PM.png
 
I can not find a section with any Start PV Voltage or similar text anywhere. Here is my full settings list. Signature Solar did help me with most of these, the ones that were changed anyway. Since I had "dumb" lithium batteries(no Ethernet connectivity), I use lead acid, and set equalization period to 0 as the (?) tip suggests.
1733006137872.png1733006182766.png
 
I can not find a section with any Start PV Voltage or similar text anywhere
You're right, it's not there. I'd have thought the 12000xp was similar enough to the 18Kpv that they'd have a similar UI, but I guess not.

Try turning off one of the breakers when it gets stuck tomorrow morning, if that doesn't do it, turn that breaker back on and open the other one. [Monday do it in the opposite order.] Maybe that'll shed some light on the problem...
 
This seems a bit odd for me to understand. In the morning, does the voltage not slowly creep up from 0?
Not really, as soon as they see light the voltage spikes until there is enough light and the MPPT finds it's power point and starts making power.
In the attached graphs you can see when they first showing voltage but there wasn't enough useable light to make power, once there was enough light to make power the voltage dropped.
 

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You're right, it's not there. I'd have thought the 12000xp was similar enough to the 18Kpv that they'd have a similar UI, but I guess not.

Try turning off one of the breakers when it gets stuck tomorrow morning, if that doesn't do it, turn that breaker back on and open the other one. [Monday do it in the opposite order.] Maybe that'll shed some light on the problem...
Likely the software was written slightly different and EG4 did not expose that specific setting via the web interface for the 12000. It might be because that setting has limited usage.

On the 18kpv when looking at the underlying modbus data/settings I see a fair number of settings that are not exposed to changed on the web interface/lcd interface.
 
You're right, it's not there. I'd have thought the 12000xp was similar enough to the 18Kpv that they'd have a similar UI, but I guess not.

Try turning off one of the breakers when it gets stuck tomorrow morning, if that doesn't do it, turn that breaker back on and open the other one. [Monday do it in the opposite order.] Maybe that'll shed some light on the problem...
I did take one panel out of the series already. It should drop it to about 400v or so I would suspect. Maybe a tiny bit higher.
I use a double pole breaker. So it is either on or off for both sides. I am only using 1 PV line, out of the 4 available, splitting the 2 mppt controllers. so just 1 series line, and 1 breaker, and 10 panels(9 in the morning tomorrow). The amps should still max out around 11 or 12.
Not really, as soon as they see light the voltage spikes until there is enough light and the MPPT finds it's power point and starts making power.
In the attached graphs you can see when they first showing voltage but there wasn't enough useable light to make power, once there was enough light to make power the voltage dropped.
I see your voltages there, and I was expecting somewhat similar charts. What is your Open Circuit Voltage? I would just like to compare.

Also here is some data to look at with my voltage recorded from the inverter(11/28). I didn't even know this existed until now. Not sure if the data points are as accurate as yours(for voltage). I used data from a few days back due to the better weather (mostly clear skies), giving a much more consistent performance. The 2nd chart is from the dashboard on the same day. Just so you can see the bigger picture. I am not loading this thing down at all, at least not much yet, but this doesn't change the issues I am having. And others with bigger loads.

You can also see in these charts exactly where I reset my breaker around noon. It probably didn't show a dip to 0 on the cart due to my actions of resetting the breaker within 20 seconds, maybe less.

I hope this fills in more clues, and I suspect it just a firmware fix as well as some others have mentioned.
1733015743526.png1733015568138.png
 
I see your voltages there, and I was expecting somewhat similar charts. What is your Open Circuit Voltage? I would just like to compare.
~360VOC for inverter 1 and 287VOC for inverter 2.
Note that I'm running a different brand AIO, I was just illustrating what voltage looks like at first light.

Here's my 410VOC SW string from earlier today.
1000012528.jpg



I did take one panel out of the series already. It should drop it to about 400v or so I would suspect. Maybe a tiny bit higher.
I use a double pole breaker. So it is either on or off for both sides. I am only using 1 PV line, out of the 4 available, splitting the 2 mppt controllers. so just 1 series line, and 1 breaker, and 10 panels(9 in the morning tomorrow). The amps should still max out around 11 or 12.
These results will be interesting to see.
 
~360VOC for inverter 1 and 287VOC for inverter 2.
Note that I'm running a different brand AIO, I was just illustrating what voltage looks like at first light.

Here's my 410VOC SW string from earlier today.

These results will be interesting to see.

Thank you. I see the MPPT is attacking the solar to start, keeping the voltage well in range(even if it was cold and could have been out of range compared to the circuit was at open voltage).
This is mostly what I expected in the morning, as the spikes don't ever reach your OCV. So this will likely not change much, but like you said, still will be interesting. Simple changes like taking 1 panel out takes a few minutes and if it can point to a problem on my side or EG4 side to help create a fix, and not damage anything, I am all for it. What is a few hours or a day lost? At least for me being grid supplemented.
 
I use a double pole breaker. So it is either on or off for both sides.
But you have one set of double-pole breakers in each of those two external boxes, one for each array, to feed the separate MPPT inputs, no?

Instead of turning the (rotary) switch on the inverter, which disconnects both arrays from both MPPT inputs, try turning off one (or the other) of the double pole breakers in those external boxes, so you can see if disconnecting one string from one MPPT input will help.
 
I am also having the same issue with the same inverter. Issue starts in the morning. It stays at 120V until I either turn off PV from EG4 Switch, or turn off PV at breaker. I have 1 series string that sits at 445v open circuit. It then goes to an appropriate ~365v or so on after the "reset".

I did receive an Email from the level 2 tech support team, mostly stating they are aware of the issue and may have a fix. But that was all that was stated for now. I will update here if they give me good advice or changes. Since this is an issue that can only be tested once each day essentially, this problem could take a long time to get figured out, unless i tarp down all my panels lol.
I’m crossing my fingers that it will be solved with a firmware update SOON. ;-)
 
@Joehaynie Since our Open Circuit Voltage is close to the same. I am going to reduce my series string down one panel for tomorrow morning to see how it performs. Worse thing is I just add it back in when I turn the system off, or maybe figure out somewhere the issue could be stemming from. So far I have had 5, out of 5 days since it was put into operation that this has been an issue, so any change could rule out other troubleshooting, even though we are staying well within the spec sheet. It might be worth doing a half string tomorrow on one of your sets to see if there is any change, if you have the wire length ability in your setup to do that.
Thank you. I won’t be able to try that for a couple of days. I have a whole new set of issues with the inverter. Yesterday the inverter registered an overcharge in the battery bank and shut off the power to the house. I went through a shut-down and start-up process and now the lights are back on but the inverter is only using power from the grid—not from the battery or the PV arrays even though they have power to contribute. I’m waiting until Monday so I can call the folks at SignatureSolar to get that problem solved. Then I can go back to troubleshooting the 120V constraint.
 
But you have one set of double-pole breakers in each of those two external boxes, one for each array, to feed the separate MPPT inputs, no?

Instead of turning the (rotary) switch on the inverter, which disconnects both arrays from both MPPT inputs, try turning off one (or the other) of the double pole breakers in those external boxes, so you can see if disconnecting one string from one MPPT input will help.
I’m the one with two arrays and two breaker boxes (I’m the original poster). I believe @Aether has only one array and one breaker box. Beyond that our systems seem pretty similar. I also have LiFePo4 batteries that aren’t on their list so we’ve both had to set them up as Lead-Acid. His single array is about the same capacity as each of mine. It’s also interesting to note that he is having the same problem in Florida so I don’t think cold is a factor.
 
Thank you. I won’t be able to try that for a couple of days. I have a whole new set of issues with the inverter. Yesterday the inverter registered an overcharge in the battery bank and shut off the power to the house. I went through a shut-down and start-up process and now the lights are back on but the inverter is only using power from the grid—not from the battery or the PV arrays even though they have power to contribute. I’m waiting until Monday so I can call the folks at SignatureSolar to get that problem solved. Then I can go back to troubleshooting the 120V constraint.
Do you know what BMS is in your batteries? Can you communicate with it via Bluetooth or PC?
It sounds to me like the BMS is in protect mode from the overcharge.
What voltage are you charging to in lead acid mode?
 
But you have one set of double-pole breakers in each of those two external boxes, one for each array, to feed the separate MPPT inputs, no?

Instead of turning the (rotary) switch on the inverter, which disconnects both arrays from both MPPT inputs, try turning off one (or the other) of the double pole breakers in those external boxes, so you can see if disconnecting one string from one MPPT input will help.
I only have 1 input, 1 array, 1 string, 1 double pole switch, 1 black and red PV line in, All panels in series.

This suggestion doesn't help me.
I’m crossing my fingers that it will be solved with a firmware update SOON. ;-)
I think this is the only option. Taking 1 panel off my string did nothing. I might try 2 for tomorrow morning.
Thank you. I won’t be able to try that for a couple of days. I have a whole new set of issues with the inverter. Yesterday the inverter registered an overcharge in the battery bank and shut off the power to the house. I went through a shut-down and start-up process and now the lights are back on but the inverter is only using power from the grid—not from the battery or the PV arrays even though they have power to contribute. I’m waiting until Monday so I can call the folks at SignatureSolar to get that problem solved. Then I can go back to troubleshooting the 120V constraint.
Wow, that is annoying. Well sorry to hear about that. And your parameters are set correctly for charging I assume?
The BMS on the battery should stop an overcharge.
I’m the one with two arrays and two breaker boxes (I’m the original poster). I believe @Aether has only one array and one breaker box. Beyond that our systems seem pretty similar. I also have LiFePo4 batteries that aren’t on their list so we’ve both had to set them up as Lead-Acid. His single array is about the same capacity as each of mine. It’s also interesting to note that he is having the same problem in Florida so I don’t think cold is a factor.
This is interesting. So we are discovering that we both are on Lead Acid mode. Maybe this change is affecting another change in the software causing the MPPT to behave how it is.

Also, just in case it was missed by anyone, taking 1 panel out of my series array 9/10 did not change anything this morning. It still sat at 120V.
I put it back in for the rest of the day to get maximum absorption.

It would be interesting to note, if anyone else has the same issues as us, and is running in Lead Acid mode. I think this is rare for people to be on this setting. Maybe someone can make their smart batteries into dumb batteries for a morning and set it to that, and disconnect their com cables? I would doubt this could cause any damage, but maybe make sure just in case.
 
Just an update, I have not heard from SigSolar yet. Also 8 out of 10 panels in series string lead to the same result this morning.
 
I’ve had my EG4 12000XP inverter installed for a couple of weeks, but I’ve noticed a troubling trend. The inverter itself seems to be limiting the voltage (and consequently the wattage) of both of my PV strings to 120V. The strings themselves (11 330W panels each) are actually generating over 400V. When the sun comes out every new day the voltage on my PV strings gets limited to 120V until I reset the PV switch at the inverter. Even then the voltage at the inverter is less than the voltage coming from the strings. By the next day it goes back to 120V and I have to reset it again. Here’s a short video demonstrating the problem.

So far it has stumped my friends at Signature Solar, though they are working on it. Anybody here have any idea what may be going on?

Would you be able to send me the serial number for this inverter? I would like to update the firmware to see if this issue related to the firmware version.
 
I only have 1 input, 1 array, 1 string, 1 double pole switch, 1 black and red PV line in, All panels in series.

This suggestion doesn't help me.

I think this is the only option. Taking 1 panel off my string did nothing. I might try 2 for tomorrow morning.

Wow, that is annoying. Well sorry to hear about that. And your parameters are set correctly for charging I assume?
The BMS on the battery should stop an overcharge.

This is interesting. So we are discovering that we both are on Lead Acid mode. Maybe this change is affecting another change in the software causing the MPPT to behave how it is.

Also, just in case it was missed by anyone, taking 1 panel out of my series array 9/10 did not change anything this morning. It still sat at 120V.
I put it back in for the rest of the day to get maximum absorption.

It would be interesting to note, if anyone else has the same issues as us, and is running in Lead Acid mode. I think this is rare for people to be on this setting. Maybe someone can make their smart batteries into dumb batteries for a morning and set it to that, and disconnect their com cables? I would doubt this could cause any damage, but maybe make sure just in case.
So Monday morning I actually copied your parameters you posted, and my system reset and started working without running off the grid. Thank you! Because of the reset I don’t know yet if the 120V limit got resolved or not. I’ll check when the sun comes up this morning.
 
Do you know what BMS is in your batteries? Can you communicate with it via Bluetooth or PC?
It sounds to me like the BMS is in protect mode from the overcharge.
What voltage are you charging to in lead acid mode?
My batteries are made by Eco-Worthy and their BMS is supposed to be accessible via bluetooth, but the instructions in their app are in Chinese so I haven’t gotten that connected yet. I had it charging up to 58.4V, though I changed that parameter yesterday morning.
 
Would you be able to send me the serial number for this inverter? I would like to update the firmware to see if this issue related to the firmware version.
Absolutely. It is XXXXXXXXX. Let me know if you update the firmware and I’ll report back on whether anything changed. Thank you.
 
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My batteries are made by Eco-Worthy and their BMS is supposed to be accessible via bluetooth, but the instructions in their app are in Chinese so I haven’t gotten that connected yet. I had it charging up to 58.4V, though I changed that parameter yesterday morning.
You might want to try the xiaoxang app, I probably butchered that spelling, the icon looks like an elephant.

PS - I'd edit your post with your serial number and pm eg4tech with it directly.
 
The firmware has been updated, please let us know if it resolves the issue.
So, since you updated the firmware I’m not seeing the arrays being limited to 120V (we’ll see if they go back to that tomorrow), but the output from the arrays still seems very limited even though we have a full sunny day with no clouds. I have two arrays and each has the potential of generating around 3500Watts and nearly all my measurements put the volts higher than 430 on each array. You can see in the image below that the volts are hovering around 280 and watts around 800 for each array. Any ideas of a root cause for the limited PV input?

IMG_0768.jpeg
 
Limited home / battery charging loads seems why as your not sending excess to the grid.

You would need to enable grid sell to have maximum harvest from the solar.
 

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