Limitations in backup mode
The inverter is a hybrid inverter that is designed for optimal use in parallel grid operation.
If there is a grid failure, the inverter can establish its own 3-phase backup power network using an emergency generation mode, also called backup mode.
The inverter is not designed to be used permanently as a microgrid inverter. The maximum number of operating hours in backup mode is 5000 hours. The warranty for the device then expires because the load in backup mode is higher than in grid mode.
Consumers in backup mode
Be aware that not all consumers in the house grid can be supplied with energy, because the power from the battery and PV modules is not sufficient at all times. Therefore, in backup mode, it makes sense to only supply certain consumers with energy.
Compatible backup switches make it possible to divide up the supply to the house. All consumers that are not required during a grid failure are connected to the grid mode branch. Consumers that should continue to be supplied during backup mode go in the backup mode branch.
If an overload occurs in the house grid because there are too many consumers in backup mode or when a backup power network is being established, the inverter tries to establish a backup power network three times before shutting down. A message on the inverter display indicates that this has happened. If this occurs, reduce the consumers and acknowledge the message on the inverter display. The inverter then tries to establish a backup power network again.
1 | PLENTICORE G3 |
2 | KOSTAL BackUp Switch (manual switch) |
3 | Mains operation |
4 | Backup mode |
5 | Consumers in grid mode |
6 | Consumers in backup mode |
Be aware of the following points:
- The power in backup mode depends on the installed PV power and the available battery power.
- It is not possible to use all consumers in backup mode.
- For reliable operation, do not connect any consumers that rely on having a stable energy supply.
- Do not connect any consumers that have a larger total usage than the maximum backup power.
- Do not connect any consumers that can cause very high startup currents. In backup mode, some electrical devices may not function correctly due to the starting currents being too high. In backup mode, only connect consumers that are absolutely necessary.
- The inverter only switches to backup mode when the conditions are met. This means that the consumers must not exceed the power limits available in backup mode. In this case, reduce the consumption (shut down consumers) so that the inverter can switch to backup mode.
- Self-consumption control via switched outputs in backup mode has no function. Only switched outputs for events can be used.
- Do not switch the inverter off in backup mode if PV power is no longer available. If it has been switched off, the inverter cannot establish a new connection to the battery. Backup mode is only continued once there is sufficient PV power available again.
- If there is no longer any PV power present and the battery has been discharged to the set min. SoC, backup mode is terminated.
- If the battery SoC falls below a minimum limit (dependent on manufacturer, typically 3%) during a power cut, the battery cannot be emergency charged and the storage system shuts down automatically in order to prevent deep discharging.
Switch the battery’s fuse back on as soon as there is sufficient PV energy. The inverter then charges the battery to the set Start SoC for backup mode and continues backup mode. - The backup mode function must be activated in the inverter's Webserver.
- Active power reduction in terms of power output and input has no function in backup mode.