This unit consists of a 3-stage spur gear unit with 4 shaft. One and two stage gear units can thus also be realized. Each shaft can be equipped with an additional flywheel mass to increase the angular inertia. The gears are driven using a cable drum and a variable set of weights that are lifted using a removable crank. Unwinding is prevented by a safety catch a clamping roller free wheeling hub prevents undesired coiling of the cable. The weight is arrested by a receptacle with an impact attenuating insert.
A hand brake facilitates gentle braking. The transparent protective cover prevents unintentional contact with the rotating parts. All four shafts are fitted with inductive sensors for measuring the speed. A chart is used to record speed-time diagrams from which the angular acceleration can read.