In what scenario would you likely observe a higher available fault current?

The scenario where you would likely observe a higher available fault current is when a system is connected to a utility secondary network. This is because utility secondary networks are designed to provide a robust and reliable power supply with multiple feeds and pathways. In such systems, there are typically more sources of current available to contribute to a fault than in isolated systems or systems with only local generators.

In a utility secondary network, the interconnected nature allows multiple utility sources to contribute to the fault current, which can lead to higher fault current levels due to the combined capacity of these sources. Additionally, since secondary networks usually operate at lower voltage levels while maintaining high current capabilities, this arrangement can also lead to more substantial fault currents compared to systems that have limited source availability, such as isolated circuits or single generators.

The presence of transformers alone does not guarantee high fault current levels, as their impact depends on how they are connected and the overall system design. Isolated circuits, by definition, have limited connections that prevent the flow of current from external sources during a fault, which also results in lower available fault current compared to interconnected systems.