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MPP LVX6048WP How to set only use battery/PW if grid is unavailable ?

Redacted

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As the title states, I am trying to keep the battery for backup purposes and only use solar and grid for now, I have 4x450 panels, the LVX6048WP and a Jakiper 100ah battery that is running a "critical service panel"

I have been playing with settings and it seems I can not get the battery to not discharge when PV is not available.

Has anyone set this up before? is it a bad idea? what am I missing?

TIA
 
Hello, let me start with simple disclaimer to say that I have no hands-on experience with an LVX6048.

With that said, I would read the manual (if you haven't already done so) and scour the settings (which it sounds like you already did to some extent), and continue to check if there is a way to set it up to behave like that before moving on to other potential solutions. You could also ping MPP Solar to ask them if there is a setting configuration to adjust which could provide this desired behavior (like favor grid when solar not available or something).


But the other point I mainly wanted to mention here. The LVX6048 does have the supported ability to operate in 'batteryless' mode if running as a single unit (not parallel stacked). I wonder if you could put in a battery disconnect switch, which would allow to disconnect it from the unit when charged up to the desired level, then the all-in-one would operate in 'batteryless' mode until such time you brought the battery back into the loop.

Just a thought which might be worth looking into. LFP have low self-discharge, so they can sit for extended periods without losing a notable amount of SoC, while not being connected to a charger.
 
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@Samsonite801 what an elegant solution, relying on software vs a hardware switch. Perfect! It of course is left to me to remember to charge the battery. I will consider this, I may do this on top of figuring out the settings.

Unfortunately the documentation is not fantastic, there is definitely some things lost in translation. That along with some of the worst management software I have seen in a while. I actually got solar assistant running and that has made things a lot easier with the historical information etc.

I will keep digging around, there has to be some settings to make this happen.

Thanks for the information on the LiFePo I have only dealt with smaller drone LiPo batteries etc
 
*solved


Using solar assistant I was able to set some battery parameters using the emulated BMS due to the MPP connected BMS is apparently wildly off.

"Voltronic inverters (Axpert, MPP Solar, Mecer, Kodak, etc.) that don't have a BMS communication cable will have a very inaccurate battery state of charge (SoC) with lithium batteries because they determine the SoC by voltage. We recommend using a battery BMS cable or the Emulated BMS"

So i have now enabled the emulated BMS and have set parameters to not discharge under 90%, that should keep them topped up and ready for any outages.
 
*solved


Using solar assistant I was able to set some battery parameters using the emulated BMS due to the MPP connected BMS is apparently wildly off.

"Voltronic inverters (Axpert, MPP Solar, Mecer, Kodak, etc.) that don't have a BMS communication cable will have a very inaccurate battery state of charge (SoC) with lithium batteries because they determine the SoC by voltage. We recommend using a battery BMS cable or the Emulated BMS"

So i have now enabled the emulated BMS and have set parameters to not discharge under 90%, that should keep them topped up and ready for any outages.

Cool, I figured there must be some way to do it in software/firmware, since it is expected that many people want their solution to operate in a UPS-type mode, saving the battery for when there is no power at all from grid or solar...

I just haven't actually played with my MPP Solar all-in-ones (4x LV6548s) yet, since I'm still trying to get the shop built first, so a lot of this fine polishing configuration detail is still uncharted territory for me at this point.

I also purchased the Solar Assistant code (and installed it on an RPi here) to play around with once I get my system all deployed.
 
This is my first foray into solar and I figured I'd try this all in one system. Seems to be working pretty well, a little rough around the corners on a few things.

Now that it is here I want to run the whole house on it! But first 4 more panels and hopefully another battery.

Thanks for the help!
 
I think the proper setting should be SOL.
This mode will allow battery to discharge only when solar is available. If solar is not available, it will switch to utility/grid power.
 
I think the proper setting should be SOL.
This mode will allow battery to discharge only when solar is available. If solar is not available, it will switch to utility/grid power.
I had that set, yet I was still seeing the utility feeding the battery on the inverter screen. With the other settings I set for battery parmeters I think I am good, I will watch it over the next 24 hrs
 
Hey @Redacted, im also trying to get my LVX6048WP setup. Thanks for the SolarAssistant emulated battery suggestion, im going to give that a shot.

Set in "Grid-tie with backup" operation mode, one thing I noticed is whenever I turn off the grid breaker (simulating a grid down situation) to the inverter it shuts off 30 seconds or so with warnings 2 and 4, and doesn't backup up the loads running through the inverter using the batteries. Have you tried or manage to get this to work? Is this something SolarAssistant can help with?
 
I have moved away from Solar assistant, it seems it has not been updated for our inverter.

yes I have seen this too, The problem I think is that the software is incorrect and setting the "Battery Cut Off discharging when Grid is unavailable", is actually setting the "Battery Cut Off discharging when Grid is available" and vice versa.

Mine would not switch over until I switched them,

Now when I drop my grid input it is a millisecond cut over.

So mine is set to discharge till 48v when grid is avail and 53.5v for when grid unavail, it seems to be a good compromise and works ok. Not having sun for a few weeks is not helping!
 
I have moved away from Solar assistant, it seems it has not been updated for our inverter.

yes I have seen this too, The problem I think is that the software is incorrect and setting the "Battery Cut Off discharging when Grid is unavailable", is actually setting the "Battery Cut Off discharging when Grid is available" and vice versa.

Mine would not switch over until I switched them,

Now when I drop my grid input it is a millisecond cut over.

So mine is set to discharge till 48v when grid is avail and 53.5v for when grid unavail, it seems to be a good compromise and works ok. Not having sun for a few weeks is not helping!
I figured out how to keep the loads on when the grid goes down. I explain it in detail in this comment: https://diysolarforum.com/threads/mpp-lvx6048wp-fault-f32.53944/post-690187
 
I have moved away from Solar assistant, it seems it has not been updated for our inverter.
What did you move to as an alternative? I'm having tons of issues getting my LVX6048WP working with Solar Assistant. (I'm also having issues with Solar Assistant constantly losing the connection to my BMS and never reconnecting)
 
I'm also using:
All running using Docker Compose. When the mpp-solar project implements sending commands to the inverter I plan on making some automations using Node-Red. I would caution, you're going to have to be pretty technically savvy to run a bunch of open source projects.

My dashboard is still a work in progress but this is what I have so far. The second screenshot is HomeAssistant's default energy dashboard.
Screenshot from 2023-03-24 11-08-59.pngScreenshot from 2023-03-24 11-13-55.png
 
I'm also using:
All running using Docker Compose. When the mpp-solar project implements sending commands to the inverter I plan on making some automations using Node-Red. I would caution, you're going to have to be pretty technically savvy to run a bunch of open source projects.

My dashboard is still a work in progress but this is what I have so far. The second screenshot is HomeAssistant's default energy dashboard.
View attachment 141108View attachment 141110
I was going to try and implement some commands via ssh+running mppsolar on the Pi. Maybe using https://community.home-assistant.io/t/sshing-from-a-command-line-sensor-or-shell-command/258731. There's the problem of serializing writes and reads since mppsolar is also running as a daemon, but I'll take my chances :)
 
I was going to try and implement some commands via ssh+running mppsolar on the Pi. Maybe using https://community.home-assistant.io/t/sshing-from-a-command-line-sensor-or-shell-command/258731. There's the problem of serializing writes and reads since mppsolar is also running as a daemon, but I'll take my chances :)
Off-topic in this thread, but I managed to enable/disable the display using a Helper in HA (toggle button), 2 shell_command in HA, a new user on the Pi, and some ssh-fu. If you're interested, I can open another thread explaining how.
 
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