I noticed that when using “Self Consumption” working mode, the device would always use GRID to pass-through to power the AC even if the SOC is way above the set point. I observed that it would only use GRID to charge the battery unless the SOC is below the set point (PV can always charge), that is good. However, even when SOC is above set point (even if it is above by a lot, say target SOC is 50% and my SOC is 83%), it still pass the GRID input to AC output and not use the battery. This seems wrong, as I would want to “self-consume” the PV energy instead of using GRID to power AC out. I’ve read that there is a 10% buffer where it would continue to pass-through until SOC is 10% above setpoint, but in my case, my SOC is 83% and my setpoint is 50% and is still using GRID pass-through instead of battery. Why is that?
I have 1 x B300k and 2 x B300 connected
My max grid input current is set to 7A, charging mode is Standard.
My AC load is small, only around 70W, does this matter?
IoT v8026.12
ARM v2204.11
DSP v2174.11
BMS v1073.07
Hi snowstorm, yes something seems wrong. My unit is also set to self consumption and my SOC is currently set to 35%. My unit charges on solar with the grid being the backup. And yes you are correct as this leaves me room to get that free power. On a couple of bad solar days It will start drawing from the grid if I hit 35% and I have verified this and that it also stops the grid pass thru at 45% and switches over to the battery/inverter. Let us know what you figure out. I have no settings help for you this time as yours seem correct.
The issue I have is that it never switches away from grid pass through even if the SOC is significantly above the set point for self consumption mode. It never seems to self consume.
Have you tried changing your SOC setpoint just to see if you can get it stop grid draw? Maybe cycle the working mode a few times? IDK if it is possible it is stuck in a dif mode but showing self consumption. I can’t look at mine right now as it seems Bluetti’s servers are down in the morning and I get a greyed out connection until they restart the servers.
I was backing up my networking equipement at around 70w earlier, and it never switch away from grid pass-through. Just now, I plugged in a dehumifier and it drew total of 544 watts, and it switched away from gird pass-through to battery only. I wonder if there is a minimum wattage that is required to activate the inverter. Maybe if the load is small enough, Bluetti won’t switch to inverter as the inverter loss is greater than the load. I will do more experimentation today and see what’s going on.
Ok, I’ve done some more testing and observed that grid passthrough seems to persist even at SOC well above the setpoint if the AC load is small. With SOC 9-10% above set point of 70%, it would switch away from grid pass-through to inverter power if I load AC somewhere around 150w. If it is lower than that, it would switch back to grid-passthrough. I think this make sense as the inverter takes power to run, maybe 2% of its rating, that coupled with the 85% or so efficiency may make it not make sense to run the inverter until load is large enough. I wish Bluetti would explain this behavior more as it looks like something is wrong, or better yet, this should be configurable as there may be situation where someone really doesn’t want to use the grid in self-consumption mode.
I hooked up a bench top DC power supply to a big coil of extension cords (as a resister) and ran a more sensitive test. It looks like that when in “self consumption” mode, grid pass-through is maintained even when the SOC is well above target (in my case it was 96% vs 70% target) if the grid pass-through input is <150W. I slowly increased the power of the DC power supply and it maintained pass-through until grid input is around 150w. At which point, the grid cuts off and it goes to battery only. Interestingly, if the AC output is then reduced, it would maintain battery power until the AC output goes below around 120W or so.
IoT v8026.12
ARM v2204.11
DSP v2174.11
BMS v1073.07
@BLUETTI Can someone from Bluetti jump on an explain how this is supposed to work? Can I turn this off so it it would stop pulling from the grid if SOC is above set point. It is OK to have a few % buffer, but always using grid no matter what for small loads would prevent PV from ever being used as the battery hits 100%. Is there ability to turn this on/off. Since my loads are only around 70w, my device would basically never use solar power and only grid pass-through. Maybe something like…
Below SOC setpoint - Grid pass-through and charge
Less than 5% above target SOC - Don’t charge, continue grid pass-through
Between 5-10% above target SOC - Don’t charge, only grid pass-through for small loads, inverter otherwise
More than 10% above target SOC or >95% SOC - Don’t charge, never pass-through
All of the above assume AC load < max grid, otherwise we’ll need to use the inverter. There are probably more nuisance and edge causes, but it would be good to consider them.
I got this from Bluetti Support. This does make sense, but they didn’t specify how high of an AC load is required to turn off Grid Pass-through. My testing suggest it is around 150V. What seems out of spec is that in time of use mode, grid pass through still seems to be on during peak time with a small AC load. The desired function as described below suggest that it should always be off during peak time. I am going to do some more testing around this and see.
The activation/deactivation of grid direct connection is not only dependent on whether the SOC is above the set point, but also influenced by the load size. It is a dynamic adjustment strategy aimed at ensuring stable power supply and optimizing energy utilization efficiency.
Charging behavior:
In the self-consumption mode, the grid (AC) only charges to the preset SOC value set by the user. Once the SOC reaches this preset value, the AC stops charging, and thereafter the battery can only be charged to a higher level through photovoltaic (PV).
Grid bypass operation:
Even if the SOC is above the set value, the system may still enable grid bypass (i.e., grid direct connection) to directly supply power to the load instead of through the battery inverter output. This design is to enhance the stability of the equipment output, especially when PV power generation is insufficient or the load is large.
Self Consumption Mode
Function: Designed for areas with abundant solar.
Charging Behavior:
AC/grid charges the battery only up to a preset SOC value (PV preset).
Beyond this SOC setpoint, only PV (solar/DC) can charge the battery.
Load Behavior & Grid Pass-through:
When SOC > setpoint, loads are powered by PV and battery.
However, grid pass-through may still be active depending on the AC load size and battery SOC.
Grid pass-through turns off when:
SOC is above the setpoint AND
Load is high enough for the system to switch to battery+PV.
Grid pass-through may remain ON for small AC loads, even when SOC is above setpoint.
Time of Use Mode
Function: Optimized for areas with time-based electricity pricing.
Time Segments:
Charging Time (Off-Peak):
Grid charges battery and provides pass-through.
Discharging Time (Peak):
Grid input OFF – no charging or pass-through.
Loads powered by battery and/or PV.
Default Time (Neither):
Grid does not charge battery but still allows pass-through.
SOC Parameters:
SOC_L (Low SOC):
If battery SOC falls below this value, grid charging and pass-through are allowed regardless of time period.
SOC_H (High SOC):
Grid will only charge up to this SOC. Beyond this, only PV can charge battery.
Pass-through Behavior:
During Peak: Grid completely OFF.
During Off-Peak: Grid ON for charging and pass-through.
During Neither: Grid pass-through ON, charging OFF.
Note: Even during “non-grid” times, low AC loads may still trigger pass-through behavior depending on SOC and load demand.
4.Custom Mode
Function: Combines aspects of the other three modes with user-defined behavior.
Grid-Off + Time-Off:
Similar to Self Consumption Mode – grid is OFF, and operation depends on PV and SOC_L setting.
Grid-On + Time-Off:
Equivalent to Time of Use mode during full Off-Peak – grid charging and pass-through always allowed.
Grid-On + Time-On:
Behaves like Time of Use mode with full schedule-based logic.
SOC_L:
Ensures a minimum battery level; when SOC < SOC_L, system allows grid charging regardless of time or other settings.
I noticed that my Bluetti Apex300 behaves mostly as described. But AC pass through is always on no matter what if the AC input power is less than 150w. It doesn’t if SOC is well about set point or we are in a peak time of use period. Once pass through is off, it will remain off until AC output drops to 100-120w, then grid pass through will come back on. This prevents self consumption from ever working if your load is <150w. I wish the threshold is configurable.
Snow go back to the pic that I posted, A picture is worth 1000 words and you can see that my load is 86W, self consumption is working correctly as I have the SOC set to 35% and I am not drawing any from the grid. Maybe you got a bad unit or a bad firmware revision or it is corrupted. I would put in a ticket with Bluetti.
Ah, you are on the previous version. It is possible that they stopped the roll out of the current firmware due to other issues (like PV cutting off randomly link and link)
One thing I noticed before I update is that even thought the screen and the app is not showing grid pass-through, grid is actually passing through. I first saw this on the “Energy Statistics” view, and wondered why there was grid consumption during the times when SOC > target. Then I verified using an external power monitor on the AC input line. Once I updated the firmware, the actual behavior didn’t change, but the display on the Bluetti device and the app showed grid pass-through to match actual energy use.
