There are four different energy storage operating modes available: (1) Self Use (2) Feed In Priority (3) Backup (4) Off Grid
You can turn these modes on and off by following this path: Advanced Settings > Storage Energy Set > Storage Mode Select > use the Up and Down buttons to cycle between the four modes and press Enter to select one. Either Self Use or Feed In Priority mode must be turned ON, turning one on will automatically turn the other off. Backup mode can be turned on independently of Self Use and Feed In Priority as this mode determines how the system will behave when the grid goes down. Off Grid mode should only be turned on if the system is installed with no grid connection at all.
Within each operating mode there are two additional options: (1) Time Charging (2) Allow Charging from Grid
Time Charging lets you tell the battery when it can accept a charge and when it can discharge power. In order for this to be enabled, it must be set to "Run" and not "Stop" because if it is set to "Stop" then none of these parameters will be enforced.
The time is in 24 hour format and the Charge and Discharge windows cannot overlap with each other. The charge and discharge current values dictate how much power the battery is able to accept/provide.
Allow Charging from Grid is a simple menu that gives you two options: (1) Allow (2) Do Not Allow. As the name suggests, this setting will determine if the battery is able to accept grid power or not. If set to "Do Not Allow" then the battery will only ever charge with PV power. In certain areas, this is required; however, please keep in mind that there must be a large enough PV system to charge the battery back up all the way. If this is not the case, then the discharge rate must be reduced or the system must be set up for zero-net export to maximize how much PV power gets put into the battery.
When operating in this mode, the inverter will store as much of the generated PV power as possible. This means that all of the power that does not get consumed (demanded) by the home will be stored in the battery. If there is no battery, then the remaining power will be exported to the utility if the system is configured that way (see article Export Power Set for more details). This mode is ideal for those who want to utilize their PV power in the evening when the grid power becomes more expensive. We call this concept "energy arbitrage" or "peak-rate shaving" and believe most people will want to be using this mode over the others.
Feed In Priority
When this mode is turned on, the system will prioritize selling power to the grid. This means that the battery will not charge or discharge unless Time Charging is turned on and configured properly. Feed In Priority mode is best for people with large PV systems relative to power consumption and battery size. The point of this mode is to sell as much power as possible to the grid and only use the battery for small windows of time or for when the grid power is lost.
When operating in Backup mode, the system will only discharge power from the battery if grid power is lost. The Backup SOC is the percentage at which the system will make sure the battery does not fall below. For example, if backup SOC is 80% then the battery should not drain past 80% ever.
This mode should only be used for people that are installing the inverter completely without grid power. In fact, no cables should be landed in the "AC Grid" terminals of the inverter but only the "AC Backup terminals". When operating in this mode, the inverter will supply power to the backup loads from the PV and the battery depending on what is readily available.