High Voltage Engineering Van de Graaff Accelerator 6 MV Vertical

The Van de Graaff-generator consists of a belt of silk, or a similar flexible dielectric material, running over two metal pulleys, one of which is surrounded by a hollow metal sphere. Two electrodes, and, in the form of comb-shaped rows of sharp metal points, are positioned respectively near to the bottom of the lower pulley and inside the sphere, over the upper pulley. A high DC potential (with respect to earth) is applied to roller a positive potential in this example.