Load banks are used for testing generators, transformers, discharging batteries and UPS systems. They are used to prove the capacity of a power source or in tuning the speed and voltage regulating system in generators. They consist of elements which serve as the load. Load Banks can be designed to draw both active as well as reactive power. It is possible to have the load bank draw power at a specific power factor. The high power consumed by the load bank results in the generation of heat. This is heat is dissipated usually by forced air cooling involving fans. Load Banks are usually portable and are enclosed in containers. Load banks which draw power at different voltages are available. Load banks have provisions to incrementally increase the loads on the power source.