Adding Single Central Inverters
To add single central inverters to the site one at a time, click on the 'Central Inverter' map tool (highlighted in red below):
A yellow popup menu appears allowing you to specify the inverter type to add, along with the module type to use with this inverter, some collection effect values and which transformer instance to add any added strings to.
Then click on the map to add a central inverter instance. No physical object (that may provide shading) is added to the site -- it is just a placeholder for the central inverter.
The inverters appear in a table in the Inverters tab in the lower pane of the screen. Note the string length is set to be the default string length you defined in the 'String Length' task screen. You can change the string length in this table:
You then need to manually assign strings to these central inverters. See Assigning Strings to Central Inverters for how to do this.
However, the above method is very laborious if you have more than one or two inverters in your site. A more common way of adding inverters and automatically stringing them is to use the Specify Site Layout tool. Access this using the 'Specify...' button in the Site Layouts panel. See Specify Site Layout Tool for more details on how to use this.