EG4 12K/18K/FlexBoss Firmware FAAB-2122 (Now replaced by FAAB-2525)

[Redpineapple]

THIS FIRMWARE IS NOW REPLACED BY FAAB-2525!
https://diysolarforum.com/threads/new-18kpv-12lv-flexboss-and-gridboss-firmware-9-28.113344


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Old notes / bugs


Wish I saw this earlier. Really wish that EG4 had some sort of alert for new firmware and notified the end user when the log into the monitor center or Application

@EG4TechSolutionsTeam you might want to make this a popup on your portal... just my .02 cents.

Be warned! This update is full of bugs and kinda 1/2 baked! Read the bugs and change logs before going forward! There is no going backwards in firmware!

If you do update the flex boss, you will also need to update the grid boss firmware at the exact same time if you are running a grid boss system!

Updating the flex boss and also the grid boss may or may not default your settings on the grid box as well! Back up a configuration PDF of your settings before you touch anything!

New Firmware Patch Notes


Change Log

FAAB-2122​

2025-05-13​

• Based on FAAB-2021
• 1.Add Weekly Setting function
• 2.Add the function of Sporadic AC charge power function, it will cause the AC charge power to fluctuate randomly between the set AC charging power and 2% rated power.
• 3.Optimize the response speed and stability in zero export mode in meter mode.
• 4.Optimize the restart logic that modify the CT/meter, battery type and brand will not be restarted.
• 5.Improve the issue of reading the RGM settings.
• 6.Improve the issue of power display on Micro-Grid mode.
• 7.Improve the issue of not stopping at the Stop Discharge Volt of forced discharge.
• 8.Improve the issue where the LCD display on the load power side lacked Smart Load power when the Micro Grid plus Smart Load mode were enabled.
• 9.Improve the issue of increased charge power when setting the Charge Last mode.
• 10.Improve the issue of abnormal load display in web page flow chart during parallel mode.
• 11.Improve the issue of getting phase lost warning when switching from on-grid and off-grid in three phase parallel mode.

I have not updated yet but I saw it just now
**EDIT**
I've updated as of 7/15 and ran into some issues (along with other users).

A few bugs or unreported changes.

1. A full power cycle may be required to fully update this firmware. YMMV - https://diysolarforum.com/threads/new-eg4-12k-18k-flexboss-firmware.108200/post-1496716
2. For the FB21 the fans now come on at 4000 Watts and are not 100% going. There is a curve built into the logic now. This is not documented anywhere in the firmware release - https://diysolarforum.com/threads/new-eg4-12k-18k-flexboss-firmware.108200/post-1496741
3. Charge from Grid seems to be changed or having issues where it will charge outside of the time slot. The entire "time based" features seem to need some work - https://diysolarforum.com/threads/new-eg4-12k-18k-flexboss-firmware.108200/#post-1496713
4. The iOS / Apple EG4 app needs to be updated to show these new features
   1. If you use an outdated app to configure the inverter with the new firmware the app may undo / fight with some of the changes. YMMV / You've been warned.
5. If you have a dedicated screen (FB21 for sure) the touchscreen does not show the new features. Only the web portal shows the new features for scheduling
6. battery communication Sensitive issues if you are using a Gridboss. Any communication disconnects reboot the device
7. Doing quick charge does not fall off the schedule the following day. The next day will have the same quick charge schedule time you had requested the day before. Quick charge is 1 hour of time that inserts itself into your schedule
8. If you have peak shaving enabled you are not able to use quick charge. Peak shaving overrides the request. You must first disable peak shaving to quick charge
9. If you have a Grid boss attached to your Flexboss / eg4 hybrid inverter you will also need to update your Gridboss firmware - https://diysolarforum.com/threads/problems-with-eg4-app-after-firmware-update.108256/
   1. I still see the GB Firmware as up to date for version IAAB-1300 (as of 7/18/25) but there may be a newer one? Trying to get clarification on this.
10. TBD (I could go on... but their notes still need to be appended for what was fully touched

@Will Prowse have you tried this new firmware and if so can you make a video on the upgraded features?

@mciholas @TacoMeat - I'm wondering if this changed the fan speed stepping or if that's a future release (and they didn't mention it in the release notes). Please test and report back!

I'm tempted to try it especially since it has a weekly schedule now which is what I've been asking for / wanting for awhile.

Patching this will likely drop AC connections to / from the device so be warned.

Thanks!

 

[TacoMeat]

I'm not sure, I want to say it "feels" like it's a little less but I was thinking the same as you, it's not on the change log.

So far it has been fine. I'm still dealing with random Leakage | High problems. Hopefully we've addressed them after this week.

 

[Redpineapple]

@TacoMeat - the fans no longer go full tilt at 6000 but they also don’t spin up below 6000 still.

Between 8k and higher the fans go full tilt

@EG4TechSolutionsTeam - can you please rewrite your support article for the monitor center?

I’ll be calling signature solar tomorrow b/c this just doesn’t seem right

Your old document is here - https://eg4electronics.com/wp-content/uploads/2024/09/EG4-Monitor-Center-Overview.pdf

I’m technically savvy and I’m still having issues with this new update.

After updating I still can’t get the battery to ac charge based off of time the way I want.

I’m getting invalid parameters when setting info on the weekly schedule but no detail on what that error means.

I also can’t see the battery info on the web portal (but I can on the app)

Very bizarre

 

[geordi]

I don't know if this is a function of this new firmware or not, but I think it IS the firmware. When the gridBoss and FlexBoss run the battery down to minimal, the power flickers (causing things to reboot) when it switches to grid supply and starts charging the battery a bit - then it swaps back to the battery, runs it down from 5%, and blips the power again.

Don't like it at all, and it has been annoying my RV Victron inverter that is connected as a load, causing THAT to shut down entirely every time the system blips.

It was not doing this on the previous firmware. As an additional annoyance, unless I have it set for "off grid" mode, it will not utilize the batteries to carry the loads at all, where previously it would seamlessly carry the loads on the batteries and use the grid as a backup when the pack was depleted.

 

[DavidHouse]

I've been running 2122 for the past couple weeks on my 12kPV and haven't had any issues, compared to previous versions. It also didn't fix the relay cycling issue that some of us have been having, but then again the release notes didn't claim that it was going to fix it. Relay cycling thread for reference: https://diysolarforum.com/threads/e...n-battery-full-after-firmware-upgrade.103615/

Out of curiosity, does anyone know what item number 2 is in the release notes?

• 2.Add the function of Sporadic AC charge power function, it will cause the AC charge power to fluctuate randomly between the set AC charging power and 2% rated power.

 

[Redpineapple]

It’s right next to grid charge

 

[Redpineapple]

I upgraded last night and I’ve had nothing but problems I kind of regret upgrading

I can no longer charge from grid based off of time (only SOC)

I can no longer quick charge either

I am now escalated to tier 2 at EG4

 

[EG4TechSolutionsTeam]

I upgraded last night and I’ve had nothing but problems I kind of regret upgrading

I can no longer charge from grid based off of time (only SOC)

Does it not give you the option to set it, or does it allow you to set it but fail to activate?

 

[geordi]

EDIT: Ignore my misunderstanding below - the firmware bug / system performance issue is this: When there is a communication disruption between the battery and the inverter, the GridBOSS and the inverter BOTH dump all loads rather than the expected behavior of sending loads to the grid while the inverter alone stops producing until the communication issue resolves. Communication interruption is caused by the BMS in the pack throwing an error / resetting itself.

Original post with diagnostic guessing follows:

I can set quick charge (I don't want to grid charge in any other way than manual) and that works for me. I THINK I figured out the power blip issue, the "Seamless EPS Switching" set to disable seems to have the opposite effect that you might expect. When disabled, it changes modes without annoying sensitive loads. When ENABLED - it kicks things offline. This is with "off grid mode" enabled, if I disable that, then it just disconnects the batteries and feeds everything from the grid.

Although today I hit quick charge, and instead it hands the loads to the grid and sends 100% of the solar into the batteries. That's not what I asked it to do.

 

[Redpineapple]

Does it not give you the option to set it, or does it allow you to set it but fail to activate?

Gives me the option but nothing happens when I select it.

Same issue on web or mobile device.

They had me do a full shutdown (Gridboss breaker / inverter breaker / battery breaker / battery power) and then reverse the steps.

I still can’t charge

 

[Redpineapple]

I can set quick charge (I don't want to grid charge in any other way than manual) and that works for me. I THINK I figured out the power blip issue, the "Seamless EPS Switching" set to disable seems to have the opposite effect that you might expect. When disabled, it changes modes without annoying sensitive loads. When ENABLED - it kicks things offline. This is with "off grid mode" enabled, if I disable that, then it just disconnects the batteries and feeds everything from the grid.

Although today I hit quick charge, and instead it hands the loads to the grid and sends 100% of the solar into the batteries. That's not what I asked it to do.

No, no it’s not

 

[geordi]

I left mine alone after hitting quick charge, and seeing (~30 seconds later) the 300 watts from solar into the battery and 4500 from grid to the loads.... And around 5 minutes later it was properly pulling 15000 from the grid and stuffing ~11500 into the batteries.

 

[skimandan]

Yay EG4!

Thanks for adding the weekly scheduler for us folks on TOU rates!

I look forward to trying it out once my RMA is complete and my hybrid inverter will actually work with the batteries I have attached, instead of operating aa an expensive grid tied inverter.

Anyways, yay!

 

[Redpineapple]

I finally got my inverter sorted out.

The documentation on the weekly settings overrides the main page…. But it doesn’t state that in the errors found.

It’s working (for now), but quick charge still doesn’t behave for me.

I’m going to ride with my daily config for a bit and try weekly out again this weekend.

I can’t afford to be down for an extended period of time

 

[RARankin]

Out of curiosity, does anyone know what item number 2 is in the release notes?

• 2.Add the function of Sporadic AC charge power function, it will cause the AC charge power to fluctuate randomly between the set AC charging power and 2% rated power.

Very curious the point of this. For giggles I enabled it just to see what it does tonight when I AC charge. Seems like an odd feature...

 

[Quattrohead]

It varies the charge power so that it looks like a normal household load rather than a battery or EV charger.

 

[RARankin]

It varies the charge power so that it looks like a normal household load rather than a battery or EV charger.

Is it just to trick the power company into thinking you're not charging?

 

[Redpineapple]

Is it just to trick the power company into thinking you're not charging?

I'm not really sure what the purpose is but I enabled it last night and it seems to be doing as expected? Perhaps it's a battery tender setting so it's not always a linear charge into the batteries?

See below.



And look at my charge from grid last night (all over the place)

 

[TacoMeat]

Anyone run into where AC Charge Mode DOESN'T turn off? I have mine set from 7pm - "Mid-night" (23:59) and last night I noticed it didn't go off until 7 mins after mid-night and only after I pushed an updated time.

Not looking to charge battery, just handle loads (EVs).

 

[Redpineapple]

Here are some of the new settings since it's not

A. documented
B. detailed
C. clear on what it does or doesn't do.

When you upgrade to the latest firmware EG4 suggested that you do a full power cycled on the inverter not just a "reboot" to clear everything.
This was required for me to get everything operational / working correctly.

To do a full power cycle do the following (assuming you have a grid boss or AC input power)

1. Turn the breaker off going into the Inverter from your main panel (Grid Boss / etc.)
2. Turn off the breaker in the inverter
3. Turn off the breaker on the battery
4. Turn off the power going to the battery (in my case it was a power pro wall mount so it was a button)

Wait a few min's and confirm everything is dark / off

Reverse the steps 4/3/2/1


-------------------------

Here are some of the new options when you use the new firmware.

Weekly Set is an option (which takes you to the URL https://monitor.eg4electronics.com/WManage/web/maintain/remoteSetWeekly)



From that new page you have the option to set weekly for any of the working modes.



There is a lot here to work with and I'm glad they finally have a weekly schedule.

I also noticed that the EG4 app needs to be updated to reflect this change. Some settings on the iOS App will undo (break?) what you want to see or change on the inverter. I think this is where 1/2 my issues came with with the upgrade. I would do the upgrade and log into the app to look at something only to find out the app had undone or modified what I actually wanted.

 

[Redpineapple]

Anyone run into where AC Charge Mode DOESN'T turn off? I have mine set from 7pm - "Mid-night" (23:59) and last night I noticed it didn't go off until 7 mins after mid-night and only after I pushed an updated time.

Not looking to charge battery, just handle loads (EVs).
View attachment 312758

Yes same issue.

Make sure that you didn't set anything via the app, as the app seems to undo what you want (at least that is my experience)

 

[Redpineapple]

I also confirmed the fans kick on at 4000 watts now (manually set the AC charge to be 4000 watts) and saw the fans come on and not at full blast (I'd say 70%). At 6000 watts they once again went full tilt.

For those of you who are reading this and wondering what I'm talking about, look here at the Flexboss 21 Overheating Thread - https://diysolarforum.com/threads/f...g-battery-charging.103676/page-5#post-1456748

I ended up adding a 3rd party cooler to the top of my FB21 to constantly pull air over the cooling fins so I don't have this issue. It's a still an issue but possibly "slightly better" now? Hard to tell.

There are some bugs in this release still and some other changes that aren't not documented / in their release notes.

 

[geordi]

One of the bugs seems to be that they made the battery communication MUCH more sensitive - and if it loses comms with the battery for any reason (or no real reason at all!) THEN IT SHUTS DOWN EVERYTHING VIA THE GRIDBOSS.

THIS is why my power keeps shutting off apparently - it did it in the middle of the day today and there certainly wasn't any reason to power off - but it did anyway, twice in the span of 2 minutes. I was able to finally see an event, communication lost with the battery. The reboot last night was "battery low voltage" followed promptly by "battery open" and the GRIDBOSS opening EVERYTHING for another reboot of the power.

THIS SHOULD NOT BEHAVE LIKE THIS - especially when there is grid power present! This is a heck of a bug, honestly.

 

[Redpineapple]

Found another bug.

If you quick charge (which does charging for 1 hour) it sticks around the following day and does not auto remove itself from the schedule.

If you try to quick charge while you are peak shaving you also can’t charge (peak shaving overrides your manual request to charge)

 

[geordi]

I have not seen that scheduling bug on mine, but I'm over this firmware. It isn't even logging the loss in communication every time, but it pulled the batteries down to 4% (48.9v) which is OVER THREE VOLTS per cell, well within the spec range of 2.8-3.65. And then it rebooted on me again.

The BMS (BasenGreen / Tianpower) batteries should not be cutting communication / cutting off the pack, but the inverter and the Gridboss SHOULD NOT be dumping everything when grid is available.

How do we roll back the firmware? It wasn't doing this last week before this firmware. My Victron inverter in my RV (connected as a load to the EG4 GridBoss via normal house load panel) would sometimes reboot itself in the very early AM - but I thought that might have been a frequency issue. Maybe it was this same issue, and it is just happening more often now for reasons I haven't figured out yet.

I had a thought though tonight in trying to understand why this keeps happening randomly. It seems like it only happens when the batteries are at a lower SoC - which would fit with a loss of communication - MAYBE the BasenGreen boxes and their TianPower BMS units are the issue, and there is an error being set inside THEM - but since the communication is not 100% compatible, they aren't sending that error to the EG4, AND the error only appears in their software while it is happening. As soon as the condition clears, any record of the error is also gone.

Losing communication with the battery (like if I pulled out the network cable) makes the GridBoss freak TF out, and dump ALL power connections. I don't know why. Why doesn't it fail over to the grid instead? Maybe the issue is a cheap Chinese BMS that is falling over and dumping the communication for whatever reason, and that's why the FlexBoss and GridBoss are cutting all power.

I'd be HAPPY to swap out the BMS - if I knew that a new one would plug right in with the same connections inside? Anyone know if that's the case, are they all pretty much using the same connections?