Before starting the test, choose test method, and estimate an initial mass and Δm. Start the test. If the first specimen fails, decrease the mass of the falling dart by Δm. If the first specimen is not a failure, increase the mass of the falling dart by Δm. Continue the test according to this rule. In brief, increase or decrease by Δm according to whether the former specimen is a failure or not. After 20 specimens, calculate the total number of failed specimens N. If N equals to 10, the test is over. If N is less than 10, add specimens and continue to test until N equals to 10. If N is greater than 10, add specimen and continue the test until the number of non-failure specimens reaches 10. Then the tester calculates the test results automatically according to specific formulas.
This instrument conforms to various national and international standards:
ASTM D1709, ISO 7765-1-1988, JIS K7124-1, GB/T 9639.1-2008