Persoz pendulum

The instrument consists of a pendulum which is free to swing on two balls resting on a coated test panel.

The hardness of any given coating is given by the number of oscillations made by the pendulum within the specified limits of amplitude determined by accurately positioned photo sensors.

An electronic counter records the number of swings made by the pendulum The pendulum consists of balls which rest on the coating under test and form the fulcrum.

The two pendulums differ in shape, mass and oscillation time, and there is no general relationship between the results obtained using the two pieces of equipment.

In either case, the test simply involves noting the time in seconds for the amplitude of swing to decrease from either 6 to 3 degrees (Konig pendulum) or 12 to 4 degrees (Persoz pendulum).