Fox ESS Resources for EP11 Batteries & Hybrid Inverters

06/10/2025 | HEG™ | Home Battery

Congratulations on the installation of your EP11 Fox ESS Battery with Hybrid Inverter. The battery configuration can vary depending on the existing infrastructure at your property and whether you have existing solar. HEG attempts to ensure that most installations are DC-Coupled where possible, which means that the battery can be recharged by your solar in the event of a multi-day power outage.

Essential Loads / Emergency Power Supply / Off Grid Mode

With most Fox ESS Hybrid Inverter / EP11 Battery installs, there are either 1, 2 or 3 circuits in your switchboard that receive battery power when the electricity grid goes down. The quantity of circuits depends on how much amperage is available on the EPS (or Emergency Power Supply) of your inverter and battery in combination (it gets a bit technical!). Note: Circuits represent a grouping of lights, power points and/or appliances at your dwelling, not just a single light or power point. These circuits are referred to as “essential loads” because they are deemed to be important circuits to maintain during an outage, such as lights, power points that provide electricity to routers, fridges and charging stations.

It is important to know that when your dwelling loses grid power, then not all items in your home will be backed up – only the items that are connected to the essential load circuits. Additionally, because the essential loads are routed via the Fox ESS hybrid inverter, when the inverter is switched off, then the power to the essential load circuits is disabled i.e. they will receive no power.

Fox Cloud 2.0 Overview

The Fox Cloud 2.0 App allows monitoring and configuration of your Fox ESS inverter and battery system. It is typically accessed via an app or via a web portal. Here is an overview of its operation.

https://www.youtube.com/watch?v=CbwCep5Y6CI

Quick operational tips for the Fox Cloud 2.0 App

Swipe left on the Home Screen to show more information, then scroll down to show various detail charts. These charts can be viewed by day, month, year or “Lifetime” by selecting the appropriate option at the top of the screen.
Click on Devices (bottom of screen) and then on battery-1 (or other batteries) to access configuration details.
You can specify times to charge up the battery from the grid (Force Charge Time) during off-peak tariff periods, specify the Battery Reserve Capacity and System Minimum State of Charge (SOC)^.

^ Battery Reserve Capacity is the amount of energy in a battery that is kept aside for potential emergency backup during a utility outage, while the System Minimum State of Charge (SoC) is the percentage of battery capacity below which the battery will not discharge for general use. The minimum SoC setting ensures there is sufficient energy to power essential loads during a power failure, which is the reserve capacity, while the general setting allows the battery to discharge for daily use down to a lower level to maximise energy use.

Resetting the Battery

Sometimes the Fox ESS battery will need to be reset. This may happen if there is a need to clear an error code, or wifi connectivity has been lost and you want to try to re-establish it, a power fluctuation that has caused an issue or if a manual changeover switch has been used, or as directed by Help Desk staff. In these cases, simply hold the silver button at the top-right side of the EP11 battery in for 5 seconds until you hear/feel a click, then wait for 1 minute and then hold the button in again for another 5 seconds.

Top right of EP11 Battery showing reset button

Fox ESS Cloud Monitoring Web Portal

This interface uses the same login details as the Fox Cloud 2.0 app, but is able to show more indepth and clearer graphs: https://www.foxesscloud.com/login