Why Isn't There a Setting on the EG4 18Kpv to NOT Discharge the Batteries When Grid is up?

[skoshorek]

I bought the EG4 18Kpv and 6 LifePower4 batteries to have backup power if the grid goes down. My existing grid-tied solar system is AC coupled to the new inverter, and the entire system is set up with my utility for exporting back to the grid. I want the full 100% of battery capacity to be available when the grid goes down, so the system can last as long as possible before the batteries are drained.

Here's the problem (unnecessary limitation?) with the 18Kpv that I've run into. The new inverter insists on draining 10% of my battery capacity as soon as the sun goes down, and the batteries remain at 90% SOC till about 10AM the next morning; when there MAY be enough solar power to start charging the batteries back close to 100%. If the grid goes down overnight I am starting out 10% behind in battery capacity. There is no setting to tell the system to LEAVE MY BATTERIES ALONE while the grid is up. Why not?

This seems to be well within the technical capabilities of such a powerful and clever inverter, but the software programmers didn't think anyone would want this, I guess. Is there some valid technical reason for needing to discharge the battery bank every day? Does anyone out there have a way around this?

I have tried to use the Quick Charge feature to work around this limitation, but Quick Charge isn't working on my system. I would guess that it is seeing the same 90% limitation on AC Charging. The funny thing is, on my laptop hitting the Quick Charge button brings up a dialog box that says the action was "Successful", even though there's no battery charging going on. That's another small issue. There are inconsistencies between each of the available monitoring and settings panels in how they respond to user inputs. It just adds to the confusion. I can live with these inconsistencies, but I don't want to live with less than 100% battery capacity when the grid goes down.

I have contacted Signature Solar about this and they say that this is a limitation that they've discussed with EG4, with no solution available at this time. I imagine that this would require a software change from EG4 or LuxPower to accomplish what I want. I sent an email to EG4 on their website, but haven't heard any response yet from them in 4 days. I'm going to send them another message in case they just missed my first one.

Is there anyone from LuxPower lurking on this site who could comment on this issue?

 

[BKY2003]

Did you try Discharge setting, On-Grid cut-off volt(V) 56 volt?

 

[skoshorek]

No, but I will. I have it set to use the SOC% as the control for now, and it only allows settings between 0 and 90%. I tried setting at values above 90%, and they weren't accepted.

 

[EG4_Jarrett]

I have contacted Signature Solar about this and they say that this is a limitation that they've discussed with EG4, with no solution available at this time. I imagine that this would require a software change from EG4 or LuxPower to accomplish what I want. I sent an email to EG4 on their website, but haven't heard any response yet from them in 4 days. I'm going to send them another message in case they just missed my first one.

I would like to look into this real quick and see what is going on and why there hasn't been a response. Can you DM me your email address that you sent the email from?

Also, I am looking into rest of the message so that I can respond appropriately. I'll be speaking to LuxPower about this issue specifically as well.

I don't want you to think that this is all that I got from the post, because I see the issue that you are talking about and would like to resolve this for you as quickly as we can.

 

[skoshorek]

Well, it looks like progress. At least the setting wasn't rejected. I switched to Voltage control and set the On-Grid cut-off to 56.0V. The batteries are presently at 99% SOC and 53.8V, according to the inverter LCD screen. I have the AC coupled solar array set up to give Battery First priority to charge the batteries when there is excess solar power, and the highest I can set the SOC% is 99. I wonder if I should also use Voltage control on the AC coupled charging. I'll leave it where it is for now, and let the forum know if it keeps the discharge from occuring this evening. Crossing my fingers. Thanks for the suggestion.

 

[skoshorek]

I would like to look into this real quick and see what is going on and why there hasn't been a response. Can you DM me your email address that you sent the email from?

Also, I am looking into rest of the message so that I can respond appropriately. I'll be speaking to LuxPower about this issue specifically as well.

I don't want you to think that this is all that I got from the post, because I see the issue that you are talking about and would like to resolve this for you as quickly as we can.

I didn't send it from my email. I used the EG4 contact page which doesn't require an email address. I also sent a message this morning on that same page. I would prefer to send my requests directly to someone's email address so I can track any responses and know if it was received, but there is no info on the EG4 site to allow that. Thanks for your interest in this.

 

[skoshorek]

I would like to look into this real quick and see what is going on and why there hasn't been a response. Can you DM me your email address that you sent the email from?

Also, I am looking into rest of the message so that I can respond appropriately. I'll be speaking to LuxPower about this issue specifically as well.

I don't want you to think that this is all that I got from the post, because I see the issue that you are talking about and would like to resolve this for you as quickly as we can.

I would like to look into this real quick and see what is going on and why there hasn't been a response. Can you DM me your email address that you sent the email from?

Also, I am looking into rest of the message so that I can respond appropriately. I'll be speaking to LuxPower about this issue specifically as well.

I don't want you to think that this is all that I got from the post, because I see the issue that you are talking about and would like to resolve this for you as quickly as we can.

Jarrett,
Sorry, but I'm clueless how to send a DM on this forum. I'm computer literate, but forum stupid.

 

[millsan1]

I put in the same request. I had a tech at EG4 reach out to me and he said he would bring it up with his team internally.

 

[BKY2003]

Might not hurt to set the discharge off grid voltage to your 20% voltage values also. So when the grid goes out it will discharge appropriately.

 

[EG4_Jarrett]

Jarrett,
Sorry, but I'm clueless how to send a DM on this forum. I'm computer literate, but forum stupid.

I sent you a message. Feel free to reply when you have time.

 

[skoshorek]

I put in the same request. I had a tech at EG4 reach out to me and he said he would bring it up with his team internally.

Nice to know I'm not just one crazy person wanting this. Now there are two of us. Yay!

 

[skoshorek]

Might not hurt to set the discharge off grid voltage to your 20% voltage values also. So when the grid goes out it will discharge appropriately.

The Discharge cut-off % off-grid was already at 20%, but now, with Voltage control, it is set for 40V. This was the default when I started the app. It seems awfully low to me, but I'll leave it there for now.

Did you try Discharge setting, On-Grid cut-off volt(V) 56 volt?

Success! Your suggestion to try the Voltage control rather than SOC% control over discharging worked. Setting the cut-off voltage to 56.0V kept the inverter from discharging the batteries, which were at a 99% SOC and 53.8V. I hadn't tried this because I figured it made no technical sense that one method of battery control would be different than the other. Obviously, this was just an oversight by whoever programmed the software. If you allow setting the voltage cut-off near max charge capacity, why wouldn't you allow setting the SOC% near max charge capacity as well. Since this works, it doesn't make much sense that using SOC% control doesn't work, except for the fact that the programmers chose not to allow higher cut-off percentages in their settings. I don't know why they would limit that, and it would only take a software change to "fix" this.

This forum has proven to be a big help to me several times, even while just lurking in the background and reading others' posts. Now to have a specific problem solved within hours is fantastic. Thanks again to everyone who responded to my issue.

Now to figure out how to use the Quick Charge function, although it is less critical now that I can keep the batteries at full charge as my default. Time will tell if my 30kWh of battery capacity and 8 kW of solar will suffice to keep me in power for more than a day or so in the summer without doing some load shedding.

 

[Quattrohead]

40 volts is way too low for that setting, I would use somewhere between 48 and 50 volts depending how much you want left in your batteries.
And yes I also found a voltage control better than state of charge so far but there are still significant improvements being made in the firmware, make sure you have the most up-to-date available to you.
And I don't know whether it was down to firmware or settings, but my quick charge did not work but now does, it's pretty slick actually.

 

[skoshorek]

40 volts is way too low for that setting, I would use somewhere between 48 and 50 volts depending how much you want left in your batteries.
And yes I also found a voltage control better than state of charge so far but there are still significant improvements being made in the firmware, make sure you have the most up-to-date available to you.
And I don't know whether it was down to firmware or settings, but my quick charge did not work but now does, it's pretty slick actually.

Yeah, it seemed pretty low for a 48V system. I'll change that setting today to something that represents about 10% SOC. I updated the inverter firmware to fA-1.0/build fAAB-1312, and the LCD firmware to v13, about a week ago.

 

[Q-Dog]

Are you trying to hold the batteries at 100% all the time? LiFePO4 batteries don't really want to be held fully charged for long periods. You should cycle them at least a little.

 

[millsan1]

Sorry to hijack thread, but I wanted to clarify my request to EG4 and SS on this.

Basically, I want my batteries to hold high SOC, prefer 100%, during the day, then go into discharge after solar isn't available, at night.

My thoughts are to run off solar and grid (if needed) during the day, but at night, allow batteries to be drawn from. I would think this could be accomplished either with a schedule, or with a combo of SOC vs Solar being produced.

I wanted this because my batteries primary role is as UPS for the house. I don't mind, and want to, draw from them in the evenings. I have about 30-40 hours of UPS from my batteries.

The problem I was having is that during the day, with solar producing, if I put a high load on the inverter, say charging my EV, the load was being fed from solar, batteries and grid, even though I had set the 18 to prioritize charging batteries.

In my case, I wanted solar to be charging the batteries and total load coming from the grid.

I was told by SS Support that when there is a big load "The inverter tries to get energy from any source". Then why have the charge batteries first setting?

 

[Quattrohead]

I was told by SS Support that when there is a big load "The inverter tries to get energy from any source". Then why have the charge batteries first setting

The inverter will supply all loads up to 12 KW, after that it will supply load from grid rather than shut down due to overload. It works really well.
You might want to clarify with EG4 your usage scenario and settings, it can be quite complex to set up but once it is sorted, it all works seamlessly.

 

[EG4_Jarrett]

Sorry to hijack thread, but I wanted to clarify my request to EG4 and SS on this.

Basically, I want my batteries to hold high SOC, prefer 100%, during the day, then go into discharge after solar isn't available, at night.

I think this is achievable. Can you send me your station name and S/N via DM? I can take a look at your settings and see what we need to do to get this working how you want it to.

 

[skoshorek]

Are you trying to hold the batteries at 100% all the time? LiFePO4 batteries don't really want to be held fully charged for long periods. You should cycle them at least a little.

Yes. I intend to have the batteries at full charge as much as possible. I've heard that the batteries don't want to stay at 100% for long periods, and I think that's why the new batteries are shipped at about 50% SOC. I will purposely discharge the batteries once in awhile, but I'm not sure how often is best yet. I'll also try to quantify what the "damage" would be to stay at full charge. Is it a big issue, or a small issue?

 

[skoshorek]

The inverter will supply all loads up to 12 KW, after that it will supply load from grid rather than shut down due to overload. It works really well.
You might want to clarify with EG4 your usage scenario and settings, it can be quite complex to set up but once it is sorted, it all works seamlessly.

Sorry for the late reply, but I thought a 200A bypass capability meant that the inverter would pass whatever power it needed from the grid, up to the 200A limit, whenever the solar wasn't adequate with the grid up. I still don't see why the battery ever gets involved in this situation.