AZ Solar Junkie
Maricopa, AZ
Hey guys - thought I would share something I discovered on the 6000xp that's saving me money.
Over the summer/fall months I was running the EG4 3000EHV with 3 of the LL V2 batteries. I would almost always get more solar energy than I could actually use with the loads I'm running off the system - never needing to actually let the system pull any power from the grid. Well, actually the system would ALWAYS draw about 40 watts from the grid any time I actually had it connected. In any case, I would leave the system configured to start charging from the grid if the batteries got down to 20%, which only happened after a rare string of bad weather days here in Arizona.
I upgraded to the 6000xp several weeks ago and set up the configuration in the same fashion. In my case I only have the small-ish backyard on the north side of the house as an option to have my solar arrays, and with the low angle of the sun this time of year they are almost always shaded by the house, so my solar production is down like more than 90% versus the rest of the year. Leaving it in this configuration, where it's running off the inverter pulling most of the power from the batteries, and letting it pull from the grid when the batteries get low - what I found in looking at all the numbers is that I was actually pulling MORE from the grid than the total load output due to the pitiful amount of solar power coming in, the internal consumption of the unit and the efficiency losses in the AC to DC conversion and the charging/discharging of the batteries, etc.
I considered just shutting down the system for now and running off my loads off the grid, because I'm using more power by having it on than I'm getting from the solar, but I discovered some things about the 6000xp that I thought I would pass along that is allowing me now to still reduce my grid usage a bit using this setup in spite of the low solar power.
The first thing I discovered is that as opposed to the 3000 EHV which always pulls ~40 watts from the grid when it's connected, the 6000XP pulls virtually NO POWER from the grid when it's powering the loads from the inverter with battery and/or PV power. I'm sure it's not absolutely zero, but it's close enough to it that the emporia Vue CT sensors don't detect any current at all.
The next thing I discovered is that if you enable the battery ECO mode (setting 20), then once the batteries get down to the EOD Battery Discharge Cutoff level (setting 12), the system switches to bypass mode and stays in that mode - only charging the batteries from whatever PV power is coming in - until the batteries get up to 90%. I can't find a setting that allows that 90% threshold to be changed. It's not the AC End SOC setting - it always seems to be 90%. I'm guessing that's just defined as part of enabling the battery ECO mode.
In any case, the important thing I found is that while the system is running in bypass mode, the power it is drawing from the grid virtually identically matches the power draw of the loads - even at night when there is no PV power coming in. Apparently the unit is only sipping a tiny amount of power to keep the internals and monitoring going, but the difference in the total power coming into the grid input and the total power going out to the loads is almost undetectable. In any case it is a totally inconsequential amount of power. I confirmed it's certainly not drawing anything from the batteries either. No current detected and after 14+ hours of no solar with the system in bypass mode the battery SOC did not change even 1%.
So I've settled on this combination of settings for anyone who might find them useful:
In the below screenshot from SA, you can see the first part of this particular day when the system was powering the loads from the batteries/PV using the inverter, and then switched to bypass mode. After that you can see no difference at all between the load and grid, and that's not just how it's being reported but confirmed by external clamp meter and CT sensors.
Over the summer/fall months I was running the EG4 3000EHV with 3 of the LL V2 batteries. I would almost always get more solar energy than I could actually use with the loads I'm running off the system - never needing to actually let the system pull any power from the grid. Well, actually the system would ALWAYS draw about 40 watts from the grid any time I actually had it connected. In any case, I would leave the system configured to start charging from the grid if the batteries got down to 20%, which only happened after a rare string of bad weather days here in Arizona.
I upgraded to the 6000xp several weeks ago and set up the configuration in the same fashion. In my case I only have the small-ish backyard on the north side of the house as an option to have my solar arrays, and with the low angle of the sun this time of year they are almost always shaded by the house, so my solar production is down like more than 90% versus the rest of the year. Leaving it in this configuration, where it's running off the inverter pulling most of the power from the batteries, and letting it pull from the grid when the batteries get low - what I found in looking at all the numbers is that I was actually pulling MORE from the grid than the total load output due to the pitiful amount of solar power coming in, the internal consumption of the unit and the efficiency losses in the AC to DC conversion and the charging/discharging of the batteries, etc.
I considered just shutting down the system for now and running off my loads off the grid, because I'm using more power by having it on than I'm getting from the solar, but I discovered some things about the 6000xp that I thought I would pass along that is allowing me now to still reduce my grid usage a bit using this setup in spite of the low solar power.
The first thing I discovered is that as opposed to the 3000 EHV which always pulls ~40 watts from the grid when it's connected, the 6000XP pulls virtually NO POWER from the grid when it's powering the loads from the inverter with battery and/or PV power. I'm sure it's not absolutely zero, but it's close enough to it that the emporia Vue CT sensors don't detect any current at all.
The next thing I discovered is that if you enable the battery ECO mode (setting 20), then once the batteries get down to the EOD Battery Discharge Cutoff level (setting 12), the system switches to bypass mode and stays in that mode - only charging the batteries from whatever PV power is coming in - until the batteries get up to 90%. I can't find a setting that allows that 90% threshold to be changed. It's not the AC End SOC setting - it always seems to be 90%. I'm guessing that's just defined as part of enabling the battery ECO mode.
In any case, the important thing I found is that while the system is running in bypass mode, the power it is drawing from the grid virtually identically matches the power draw of the loads - even at night when there is no PV power coming in. Apparently the unit is only sipping a tiny amount of power to keep the internals and monitoring going, but the difference in the total power coming into the grid input and the total power going out to the loads is almost undetectable. In any case it is a totally inconsequential amount of power. I confirmed it's certainly not drawing anything from the batteries either. No current detected and after 14+ hours of no solar with the system in bypass mode the battery SOC did not change even 1%.
So I've settled on this combination of settings for anyone who might find them useful:
- Setting 20 - battery ECO mode ENABLED
- AC Charge Setting (setting 14) - Start SOC - 20%, End SOC - 24% - just to prevent the batteries from running down further
- Setting 12 - End of Discharge Cutoff SOC - 22%
- The system runs the loads off the inverter, pulling battery and/or PV only and no power from the grid
- Once the batteries get down to my EOD Cutoff SOC setting of 22%, the system switches to bypass, no longer drawing any power from the batteries, and with virtually no detectable additional overhead draw on the grid vs. the loads. There must be SOME overhead, but it's small enough I pretty much can't even detect it.
- Each day, the batteries will charge with the sorry amount of PV power coming in - depending on the day it may only increase the battery bank SOC by 2% or on a good day lately maybe 5-10%.
- Eventually the batteries get to 90% and switches to the inverter and drains the batteries back down to the 22% threshold. That's my ONE day of grid usage savings
- Then it repeats the whole cycle.
In the below screenshot from SA, you can see the first part of this particular day when the system was powering the loads from the batteries/PV using the inverter, and then switched to bypass mode. After that you can see no difference at all between the load and grid, and that's not just how it's being reported but confirmed by external clamp meter and CT sensors.
