Inverters - EG4 Community Forum

New Flexboss21 off line

Myronbilliot — Sun, 02 Aug 2026 22:07:44 +0000

I purchased a second Flexboss21 to add to my system. I have everything connected except for the parallel cable until I get the firmware updated to match my first Flexboss21. The new Flexboss21 shows off line no matter what I do. The dongle is connected to the network and I can see it thru the app and web page but the inverter shows offline. I have just a battery, grid power and output power wires connected. I connected solar just to see and it does not have any effect, still offline.

GridBOSS + FlexBOSS21 - production metering for SREC reporting?

hicks81 — Thu, 30 Jul 2026 13:36:13 +0000

I have a FlexBOSS21 with a GridBOSS and DC-coupled battery storage, and I'm registering for SRECs in Pennsylvania, where a solar-dedicated revenue-grade meter appears to be required for systems like mine.

Your Hybrid Inverter RGM Protocol Support doc says RGM protocol integration isn't supported when a GridBOSS is in the system. Three questions:

1. Is that still accurate on current firmware, and is GridBOSS support planned?
2. Reading the doc, the WattNode CTs land on the inverter's grid input cables - so is this integration intended as improved grid-side sensing rather than a PV production meter? If I need a solar production figure for SREC reporting, does the RGM integration provide that at all, with or without a GridBOSS?
3. If the answer to (2) is no, is there any supported way to get a revenue-grade PV production number out of a FlexBOSS21 - or is an external meter on the FlexBOSS-to-GridBOSS AC conductors the only route?

Also passing along a request already raised here: lugs or a landing point on the GridBOSS for a production meter would save owners in SREC states a lot of money and rework.

12000XP Off-grid with 120v generator.

ionstorm66 — Mon, 06 Jul 2026 01:28:10 +0000

I have a 6.5kw 120v 50a generator I would like to use with my 12000XP. I don't thing chargverters can be paralleled thus only 2500w output, so my question is there anyway to use the generator or grid input on the 12000XP to charge the batteries off the 120v generator?

Flexboss 21 - PV String Anomalies (Clipping) when under high load

vMAC — Mon, 15 Jun 2026 21:44:13 +0000

I'm hoping that someone on this forum can help me with a recurring/repeatable issue that I have been having with the Flexboss 21. I've called Signature Solar number times and they don't believe the unit is functioning out of spec. As this is a the second Flexboss 21 that I've had, I'd be extremely worried if both had this same rare issue. Here is a brief synopsis of the issue, and while I'm happy to share more information, I don't know how to put it into the best technical terms, so I will just explain what I'm seeing.

First I have a Flexboss 21 (FAAB-2525) that is installed in my garage along with two EG4 Indoor batteries, and PV strings (42, 410w panels) that come off the attic directly into my inverter (no combiner, disconnect, or breakers). I then have a 60 amp breaker that backfeeds into the main breaker box. So it supplies any excess solar to the main breaker to feed loads or back to my utility for buyback.

My issue is that if I have a high load (I don't know how long it has to be, but over 30 minutes based on the logs) the PV strings will stop growing in power. So if I am pulling in 4kw @ 8am off the panels, and the load stays over a certain threshold for longer than a certain amount of time, the PV will stop growing. Today I had this happen in which my AC is running nonstop (because it's going to be 111*) and my mini-split in the casita is doing the same, and pool pump etc are all running. Due to this the PV stopped growing at 3kw. I didn't notice it, so the batteries never charged today and it kept pulling from the Grid instead of resetting the PV strings. When I notice this happens my only solution (that I know of) is to restart the inverter entirely and it will then jump from 3kw to (in the case of today) 13kw immediately. I have provided the logs from today, and a screenshot from today, when this happened. I also had this happen while I was on vacation 6/1/26 and pulled the logs and snapshot of the same (you should see the spike in Solar PV from a low number to one much higher, the only change is a restart of the inverter.

2703

2704

Can someone help me diagnose why this is happening, and how it can be fixed? I know I am not on the latest firmware, but when I seen the release notes, I didn't see anything in regards to this issue. It won't let me upload the excel from EG4 website, but if anyone needs it I can send.

Error W009 - fan stuck

GotTheKnack — Sat, 06 Jun 2026 15:25:25 +0000

FlexBoss21: Well, the fan is actually running, I slipped a small piece of paper up through the grill and it is indeed running, which leads me to believe that its a motion sensor issue. I can't determine determine if the problem is on a circuit board, or more likely in the fan, or a bad connection there. BUT, the fault light is always on and that could hide a more serious fault. So, I had better do something about it.

It appears that the fan array can be removed externally for inspection, tests, possible component replacement, etc if the Inverter is off and isolated electrically for safety purposes.

Is this fan tray available separately?
Can it be replaced "in place"?
What is the part number needed?

My system was purchased in late fall of 2025 and commissioned literally 2 hours before the end of the tax rebate expiration- kudos to all that helped me!

I have no experience with EG4 hardware support, RMA procedures, etc. So I need directions on how to proceed.

Items are all warranted under my name, the electrical contractor ordered from Soligent, by agreement with the electrical contractor, I am first line support for my system. I am experienced with heavy industrial electronics and electrical work by trade, but retired.

Allen

Is it possible to clear messages in 18kPV?

detschel — Sat, 06 Jun 2026 00:42:07 +0000

Hi, is there a way to clear the meassages / event log in the 18kPV? Setup includes two 280 indoor batteries if that matters. Thanks !

EG4 FlexBOSS18 Connection

sam126 — Sat, 30 May 2026 16:28:40 +0000

Hi, just bought EG4 FlexBOSS18...below wiring diagram is from their website. Want to know if the 200A breakers shown in the diagram (in red) is actually a same breaker and not 2 separate breakers?

2689

How to tell why GridBOSS started generator?

eg4c — Wed, 27 May 2026 20:59:44 +0000

The other day my generator suddenly started working at half past midnight. I checked generator logs and it was triggered by GridBOSS 2-wire start feature. There was no outage, and batteries were at ~50% SOC (generator is set to trigger at 30%). Generator worked for ~10 minutes, then stopped.

I have graphs of grid voltage, battery SOC and generator voltage, and I verified those statements are correct.

What might have caused GridBOSS to trigger generator? If you have a theory, tell me how to confirm.

AC Couple Enphase IQ7XS ro Gridboss?

Opalfrost98gt — Wed, 20 May 2026 16:04:18 +0000

As title states Im planning to AC couple my Sunpower Equinox system which has Enphase IQ7XS Microinverters. I'm reading that they require a specific Enphase profile to work properly with the Gridboss, Do you know what that specific profile is?

Thanks

Greg

Gridboss/flexboss feature request (conditional SOC options)

okieSolie — Tue, 19 May 2026 15:45:47 +0000

Hello i have a few feature requests for the software that would help me and I think others as well.

1. If grid goes down have an option to set charge soc to a certain amount such as 100%

1.b Or if severe weather predicted on current day or next day also have an option to set charge soc to a certain amount such as 100%

2. For SOC accuracy, option to set how often in weeks to automatically charge battery up to 100% and how far to let it go down (such as 20%).

This would be nice since would not have to do this manually, if normally keeping my batteries just for back up at 70 or 80% for example.

Thanks