FoxESS Community - Owners & Installers Forum

Hello,

I recently had a AIO-H1-5.0-HSV10.4 system installed and am concerned the installers have done something very wrong but as usual, once they received their cash they are not terribly responsive, so Iḿ making sure my understanding of how the system should function is correct before I look into pursuing them in small claims court and hiring another solar electrician to come clean up their mess.

my situation: We have experienced 8 inverter overload events during what should be normal usage , 3 during the day while the PV array is active, and 5 at night when pulling power from the batteries. Once the house load approaches 5kW, the inverter overloads and we lose all power. Iḿ talking running a half dozen lights, fridge, freezer, oven and dishwasher then turn on the washing machine and boom, power goes out. I was under the impression that while mains power is available the system should be drawing from mains if it requires more power than the PV/batteries could safely provide, and only if running on EPS when mains is lost should this be a problem? (yes, our installer connected the entire house load to EPS, known problem we are rectifying).

Watchign some videos about the systems features, etc i can only find confirmation that the power usage is prioritizing PV, then battery and lastly solar, but nothing to confirm the behaviour of the inverter overload.

Can anyone confirm for me if;

a) While mains power is available, and inverter overload/shutdown should NOT result in a complete power outage, and
b) Under normal operation, the system intelligently manages the load on the inverter and draws from mains when the load is higher than the inverter maximum safe load

Thank you for your time!

Hi

While our inverter is a 3.7 rather than a 5, and it's an H1 rather than an AIO, the same principle applies. It works as you describe, ie drawing from the mains if total draw exceeds the inverter capacity, or simply if the battery is discharged and the solar yield is unable to supply the required power.

our installer connected the entire house load to EPS, known problem we are rectifying

Yep, this is what needs fixing but you already know that!

An update for those following along, we still have our lights and power socket loads connected to the EPS port, static load of 0.2-0.7kW depending on how many lights are on, so we are fine with managing the additional appliance load manually with in EPS mode to avoid EPS overloads given the max load on these circuits could exceed 5kW if everything in the house is turned on at once.

However, the saga continues as we got a new induction cooktop and oven installed today (both on their own circuits and not connected to EPS port) and when the installer fired them both up to functional test them BOOM, inverter overload and power blacked out. Oven is rated at 3kW and cooktop 2.4kW. Grid active, according to the product page for our system "no inverter load limit during grid active periods and can export excess solar power to the grid". I call BS, as we have never been able to draw above the 5kW inverter load limit with grid active regardless of how the loads have been configured. I have seen grid consumption at night after the batteries have discharged completely on cloudy days, and daily feed ins to the grid so grid is definitely connected/active. I have a scheduled call back from FoxESS Support on Monday to go over the system with me remotely and hopefully find a configuration/setting error - will let you all know if they find something!

Did they manage to pinpoint the problem at all?