FoxESS Community - Owners & Installers Forum

Have moved into a new property with FoxESS Inverter, Battery Installed.
EPS Load displayed is the same as Total Load.

When I saw EPS load I was hopeful that it might mean we could avoid power flick overs but no the inverter records events when the mains flicks over.

Asked installer in a teams meeting and said he would get back to me on this and a number of questions.

Have new neighbours and they had a meeting with the installed and kindly invited me to sit in.
They also have the same dashboard display where EPS Load matches Total Load.
The installers technician confirmed that there was noting connected to the Inverters EPS output.

The firmware levels seem quite old. Would anybody be able to confirm that firmware updates would fix the display issue. I now realise that even if we had EPS it would not avoid flick overs as there is a 2-3 msec cutover.

Given that lots of people must have solar and battery, does the cost of implementing a UPS facility, even for a short while i.e. avoiding flick overs, mean this is only viable where there is a significant requirement that would justify the cost.

Hello and welcome Keith,


Take a look here https://midsummerwholesale.co.uk/buy/fo ... -H1-3-7-G2
You can download the datasheet/manuals

EPS (Emergency Power Supply) inbuilt. Homeowners can keep the power on during power cuts with no effect to the inverter's output power.


For firmware updates, try and install FoxCloud2.0 App on phone/tablet if you have not already using same login credentials. Bookmark this page https://www.youtube.com/@iameccles/videos
See if you can DIY the firmware update https://www.youtube.com/watch?v=dJ4jQ_zyako

If not contact the installer and ask them to push FW updates for you, or email service.uk@fox-ess.com with your Inverter SN.


Cheapest method if the above mentioned EPS function doesn't switch at all, is to get a small UPS for internet router (as most would want that running)

The answer to the EPS load = Total Load is not straight forward as there have been numerous problems with the app mis-reporting Total Load as EPS load and also different firmware versions have exacerbated the display problem.

That said your firmware is very old and needs updating, the latest firmware versions are listed here viewtopic.php?t=1927

The EPS/UPS question is a more complex subject and cost can play a significant part, to try and answer your question simply - you can run a hyrbid inverter permanently in EPS mode which means it is powering the loads, but in your case with a 3.7kW inverter you cannot run the whole house on EPS as it would trip it into overload.

The only credible answer with a small inverter is to accept that you install an EPS circuit that only runs a very limited number of devices that cannot exceed the inverters overload capacity either via c/o switch or a 'critical' power circuit that always runs off EPS.

There are numerous regulations around this and so whatever you do it is essential that you get an installer or electrician that understands the safety requirements - not least the special earthing that is required for when you are running off-grid. This is because when the grid has been lost you have to assume that it is physically disconnected and so any earth connection would be lost and has to be replaced with an isolator to disconnect your house circuits from the DNO supply and you install an earth rod that provides the earth connection whilst off-grid.

The automatic changeover switches manage all of this (when installed correctly), but some users simply wire a trailing socket into the EPS outlet and ensure that when there is no grid they use only class II devices (double insulated and electrically isolated). - this is a quite an old description of the EPS options that predates the newer ATS switches you can now buy, which may help explain options.viewtopic.php?t=52