When a new circuit is instantiated, it is created as a 3-phase voltage source named "Source" connected to a bus named "SourceBus" with a reasonable short circuit strength for transmission systems feeding distribution substations.

Figure 1. Default Circuit

The default values for the source are (see Vsource object definition):

•115 kV

•3000 MVA short circuit

Thus, the circuit can be immediately solved, albeit with a trivial result.

The circuit is also immediately available for adding a substation and/or lines for a quick manual circuit modeling task.

The default circuit model does not include a substation transformer because the user may wish to study more than one substation connected by a non-trivial transmission or sub-transmission network.