Introduction
While zappi and eddi were not specifically designed for off-grid systems and are not officially supported for such applications, their intelligent features can make them a viable option for managing energy use in an off-grid environment. However, implementing this setup requires expertise in off-grid systems, and success may vary depending on the specific application. With the right technical knowledge, myenergi devices can help optimise the use of solar energy and battery storage.
Understanding the Basic Principles
Substituting a Battery as a Grid Connection
In an off-grid system, the battery acts as the "grid" for the myenergi devices. These devices monitor the flow of power to and from the battery in the same way they would in a grid-connected system.
The use of current transformer (CT) clamps is essential for monitoring power flow and providing the necessary data for the device to manage energy distribution effectively.
CT Clamps and AC Current
CT clamps play a crucial role in the operation of myenergi devices by measuring electricity flow and helping the device determine power delivery.
It is important to note that CT clamps function only with alternating current (AC). Therefore, the CT clamp monitoring the "grid" must be attached to an AC cable that connects to the battery system and records all power flowing to and from the storage battery.
Inverter Behaviour and Float State
In off-grid systems, inverters typically reduce their output when the battery nears full charge and enters a float state. During this state, the inverter limits its output to match the energy demand of the switchboard, preventing battery overcharging.
If the inverter or battery management system includes a float relay, it can be integrated with the myenergi device to optimise performance. The float relay activates when the battery reaches float, and when wired to the eSense input, it signals the device to enter Boost Mode. The boost will automatically end when the battery exits the float state.
Step-by-Step Installation Guide
Planning and Preparation
- zappi and/or eddi
- CT clamps
- Inverter
- Materials for connecting to a float relay (if applicable)
Identify the AC cable that connects the battery to the rest of the system. This is where the "grid" CT clamp will be installed.
Installing the CT Clamps
- Attach a CT clamp around the AC cable connecting the battery to the system. This clamp will act as the "grid" CT, monitoring power flow to and from the battery.
- If the system includes multiple power sources (e.g., solar and wind), additional CT clamps may be needed to monitor these inputs.
Connecting the Device
- Follow standard installation procedures to connect the myenergi device to the electrical system.
- Ensure the device is properly configured to recognise the CT clamps and monitor power flow.
Configuring the Float Relay (Optional)
- Connect the float relay to the eSense input on the myenergi device.
- Configure the device to enter Boost Mode when the float relay activates, ensuring solar energy continues to be utilised when the battery is full.
Manual Boost as an Alternative
- Manually activating boost will draw power from the battery.
- As the battery discharges, the solar system will work to replenish it.
- The zappi or eddi will detect this solar input as surplus energy and redirect it to charge the vehicle or other loads, thereby maximising solar power usage.
Setting an Export Margin
- Set the export margin to reserve a predefined amount of solar energy for the battery.
- Once this margin is met, the device will begin consuming any remaining surplus energy.
Testing and Optimisation
- After installation, test the system to ensure the device correctly monitors power flow and diverts surplus energy accordingly.
- Continuously monitor the system and make adjustments as necessary to optimise performance.
Key Considerations
CT Clamp Placement
Proper placement of the CT clamp is essential for accurate monitoring. Ensure the clamp is installed on an AC cable that is connected to the battery system.
System Integration
The success of this setup relies on seamless integration between the myenergi device, the battery, and the inverter. Verify that all components are compatible and correctly configured.
Maintenance
Regularly inspect the system to ensure continued functionality, particularly during periods of high solar generation.
By following these guidelines, myenergi devices can be effectively integrated into off-grid systems, enhancing the use of solar energy and battery storage while maintaining efficient power management. However, as myenergi products are not designed for off-grid use, users should proceed with caution and understand that support is not available for non-standard installations.