Testing method of force measurement system of universal testing machine

Testing method of force measurement system of universal testing machine,as follows:
1. Detection of zero point drift
After preheating for the specified time, the universal testing machine is in a good working state. If the force range of the force measurement system is divided into multiple gears, it will be placed in a gear in a small measurement range, and the zero point drift is detected within the specified time. The results should meet the requirements specified in the standard.
2. Detection of discriminant threshold
The discriminant force threshold of the test machine's force measurement system is detected by the following method: In the zero test force state, at least one digital incremental change should be generated after applying a force of 0.25% FL.
3. Observation and determination of resolution
Observation and inspection during the test process through actual tests (or in combination with other test tests). The resolution of the force indicator device r should be determined by observation and calculation when both the motor and control system of the test machine are started and under zero test force.
4. Detection of all permitted errors and relative resolution
All allowable errors of the universal testing machine force are used to detect using a specified standard force measuring instrument (or special inspection weight). During testing, the level of the standard dynamometer should be correctly selected according to the level of the universal testing machine, so that the allowable value of the measurement error of the dynamometer is not greater than one-third of the allowable value of the display error of the tested machine force. The relative resolution a and relative error q , relative error of the display value of the universal test machine force measurement system, and relative error of the display value repeatability b , and relative error of the display value return journey v are detected according to the method specified in GB/T 16825.1. The relative error of zero points is calculated according to standard formulas, and each test result should meet the requirements of the standard.