When is a fuel one-line diagram required at a generator site?

A fuel one-line diagram is required at a generator site primarily when an external fuel tank is installed. This diagram is crucial for several reasons: it provides a clear and concise representation of the fuel system configuration, including connections, flow paths, and control systems, which facilitates maintenance and safety management. By having a detailed one-line diagram, operators and safety personnel can quickly assess the layout and understand how the fuel system interacts with the generator. This is particularly important in emergency situations or during routine inspections to ensure compliance with safety regulations and standards.

In circumstances where the generator is in continuous operation or if multiple generators are present, while it is important to have clearly defined systems, the requirement for a one-line diagram specifically hinges on the presence of an external fuel tank. Similarly, in cases where a fuel leak is suspected, immediate action and investigation are essential, but a one-line diagram is not a specific requirement for that scenario. The clarity provided by the diagram is most critical when dealing with external fuel sources, which involve additional complexities in the fuel handling and connection to the generator.