Which load bank control is a series of switches used to select a specific resistive load value from the generator?

The correct choice is the Kw step switches because they are specifically designed to provide a means of selecting discrete resistive loads for testing generators. In load bank testing, it is essential to apply specific load values to assess the performance of the generator under different operating conditions. The Kw step switches facilitate this by allowing the operator to make precise adjustments to the load being applied.

While the other options are related components of a load bank system, they serve different functions. The volts select switch is related to setting the voltage level but does not deal with load selection directly. The blower fail indicator is a safety feature that alerts operators to any failure in the cooling system but does not impact the selection of load values. Auto load balance refers to a system that maintains equal loading across multiple phases, which is important for operational efficiency, but it is not the method used for selecting specific resistive loads. Therefore, Kw step switches are the correct choice, as they directly address the function of selecting specific load values for testing.