FoxESS Community - Owners & Installers Forum

Hi everyone,

I've recently noticed an issue with my one of my HV2600 V1 Rev. D batteries.

For the past few days, I've noticed that the charge in my batteries would reach up to about 49% (from about 35%) and then remain that way for a couple of hours and then suddenly shoot up to 100%.

I went into the garage to check on them yesterday, and one of them seems to be flashing Red and Green for about 1-second continuously. I can't make sense of FoxESS' documentation as to what could be causing this...

My installer has also booked an engineer to inspect, but the next available appointment won't be until the end of the month. I'm just wondered if there was anything else I could do in the meantime to try and resolve it (if it is indeed possible).

What I have done so far, as well as making sure all of the cables are connected properly, is to power off the entire system using Will Eccles' fabulous guide on YouTube, and reboot everything. This cleared the indicator LEDs on the battery momentarily, but then they came back again

Edit: The Inverter shows 6 x batteries when viewing 'About > Batteries', and the app reports a total voltage of 320.8v at 100% SoC.

Please help.

The battery red light is an alarm light because the battery has detected an internal fault, i'm surprised that your BMS or Inverter isn't showing any error - if you go to your inverter panel and click Enter, History, Error Logs - is there anything showing in there related to recent battery faults.

Without a battery fault code it is hard to diagnose the problem (you would expect bat volt faults or similar), The battery voltage sounds about right for 6 packs and if the pack is continuing to operate it may be a sensor or firmware fault on that one battery pack but it isn't serious enough for the BMS to trip the contactor feeding the inverter.

Thanks for your reply and my apologies in the delay responding.

The inverter reported an under voltage fault at one point, and a list of the usual faults that occur after the system is restarted, but nothing else other than that - nothing in terms of audible alarms or any fault indicators on the BMS or anything...

I guess it doesn't really matter now as my installer has replaced the unit with a new one this morning. What is surprising though is that he did a voltage test on the individual unit and it still reported a nominal 53v

The HV2600s seem very temperamental, in my opinion...

Thanks again.

Good morning.

I have the very same issue today. single battery green and red led flashing together once every 3 seconds. Battery voltage is good for the 7 batteries i have fitted. No error messages on the BMS, just a green led and then the charge status leds.
system seems to be operating normally.

I have sent an email to FOX ESS customer support.

Alan wrote: Fri Dec 01, 2023 10:01 am Good morning.

I have the very same issue today. single battery green and red led flashing together once every 3 seconds. Battery voltage is good for the 7 batteries i have fitted. No error messages on the BMS, just a green led and then the charge status leds.
system seems to be operating normally.

I have sent an email to FOX ESS customer support.

Possibly a low temperature issue, are they located in a cold place ? - from 10C to 0C they start to derate and below 0C they are stopped from charging altogether as a protection - which battery type is it HV/ECS ?

@alan / @sipxstream:

The problems you describe are exactly what I experienced last year when it turned very cold a few weeks after our system was installed - our batteries are in an unheated, north facing and permanently shaded garage so nice and cool in summer, but barely above ambient in winter. The cure is to build some sort of insulated box for your batteries so they don't get so cold, as well as making sure you have up-to-date firmware on all the components. After doing this, ours have operated flawlessly ever since.