One line eletric diagram

[Smart $]

Here is a pretty simple example.
...

This drawing is more like a One-Line/Riser Diagram. ...

I agree. On large projects, the one line may show service (possibly include the utility transformer and primary), feeders, major distribution components (switchgear, MCC's, etc), major loads, and panelboards (no panel loads typically on one line unless considered a major load). Depending on scope of work, that can get condensed.

 

[Smart $]

I agree. On large projects, the one line may show service (possibly include the utility transformer and primary), feeders, major distribution components (switchgear, MCC's, etc), major loads, and panelboards (no panel loads typically on one line unless considered a major load). Depending on scope of work, that can get condensed.

Here's the example given in NECA 100, Symbols for Electrical Construction Drawings.