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Add the existing panels and inverter to the system design, just as you would for quoting new ones.
Then on the Solar and Battery Designer page, click the 'pre-existing' box next to each inverter and MPPT. That way their energy production is factored into the site and battery charge, but they are not added to the quote price.
Click add inverter
Select the hybrid inverter you wish to use
In the PV module section, select ‘Blank panel’
Check the ‘pre-existing’ box next to the panel name
Add the battery
Do not place the ‘Blank panel’ on the map.
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