AT420D Compound Pendulum Impact Tester is used to determine the impact toughness of non-metallic materials such as rigid plastics, reinforced nylon, glass reinforced plastics, ceramics, cast stone, electrical insulating materials, etc. Equipped with different pendulums and supports, it can carry out Charpy impact tests, Izod impact tests or tensile impact tests. « Single-chip large touch screen control, able to communicate with a PC with test software;« Replaceable pendulum and specimen supports, compatible with Charpy impact tests and Izod impact tests; « Instantaneous determination and recording of the property curve of materials during impact;« High-speed stress measuring sensor to capture signals produced in the instantaneous impact on specimens and detect angle-displacement signals at the same time;« High-precision encoder with 10000 sampling points, so resolution is up to 1/65536;« Direct display of angle on PC with an accuracy of 0.001°; « Auto calculation of test data on PC and finally obtaining and displaying impact work and impact energy and the average of results of continuous 10 tests;« Curve displays of the impact process, including the curve of dynamic mechanics and the curve of impact strength, real-time reflecting the breaking process of high polymer materials during impact;« High-speed angle displacement monitoring system and stress measuring sensor, able to display N-T and J-T curves, storable and printable;« Double-function curve contrast display, integrated printing and separate printing, convenient for the operator to contrast and analyze;« With functions of analysis on impact strength points and mechanical breaking points;« Multi-type data display and conversion;« Auto pendulum-releasing function by software or electronic pendulum-releasing function.