If you were using a pump graph, what information would not be available from it?

A pump graph, often referred to as a pump performance curve, provides essential information about how a pump performs under various operating conditions. Among the factors shown on the graph typically includes the feet of head, which indicates the pressure the pump can generate at different flow rates, measured in gallons per minute (GPM). The brake horsepower (BHP) is also represented, allowing operators to understand the power needed to drive the pump based on various flow conditions.

However, NPSHa, or Net Positive Suction Head available, is a calculation and determined by a range of system parameters, unlike the performance metrics provided directly by the pump graph. It accounts for the pressure conditions and the energy available to prevent cavitation in the pump and is calculated externally based on factors like the height of the liquid supply and system losses, rather than being illustrated on the performance curve itself. Thus, while a performance graph shows critical parameters like head and flow rate, it does not provide direct insight into the NPSHa, making it the correct choice in this context.