You can create a load classification so that it is available in the project environment. 
To create load classification for connectors
-  Open an electrical device in the Family Editor. 
- In the drawing area, select an electrical connector. 
- On the Properties palette, click the button to the right of the value for Load Classification. 
 
- In the Associate Family Parameter dialog, click Add Parameter. 
- On the Parameter Properties palette, create a load classification parameter. See Creating Project Parameters.