An electronic load bank tends to be a fully programmable, air- or water-cooled design used to simulate a solid state load and to provide constant power and current loading on circuits for precision testing.

​A combined load bank usually consists of both resistive elements and inductors that can be used to provide load testing at non-unity PF (lagging) including the capability to test the generator set fully at 100% nameplate kVA rating.

A capacitive load bank or capacitor bank is similar to an inductive load bank in rating and purpose, except leading power factor loads are created, so reactive power is supplied from these loads to the system instead of vice versa. Hence for a mostly inductive load this can bring the power factor closer to unity improving the quality of supply. These loads simulate certain electronic or non-linear loads typical of telecommunications, computer or UPS industries. Fluorescent light tubes are also capacitive loads.

An inductive load consists of an iron-core reactive element which, when used in conjunction with a resistive load bank, creates a lagging power factor load.

A resistive load bank, the most common type, provides equivalent loading for both generators and prime movers. That is, for each kilowatt (or horsepower) of load applied to the generator by the load bank, an equal amount of load is applied to the prime mover by the generator.

The three most common types of load banks are resistive, inductive, and capacitive. Both inductive and capacitive loads create what is known as reactance in an AC circuit. 

Load banks are used in a variety of applications, including:
Factory testing of turbines and engine diesel generator sets

Load bank is a piece of electrical test equipment used to simulate an electrical load, to test an electric power source without connecting it to its normal operating load.