Horizontal to Vertical: An Increase in Effective Calibration Using Rope Fixtures

Abstract

At our laboratory, the calibration of a cable tension meter was traditionally done in the horizontal plane. This was done primarily due to the configuration of the test machine used at the time of calibration. The accuracy of this measurement was affected by additional forces such as cosine error and gravity affects on the unit under test itself. The implementation of a new, vertical testing machine in our laboratory offered us the opportunity to move the calibration to it and save time while improving the uncertainty of the measurement. However, this action was met with some difficulties that caused us to identify an important improvement not only to our methodology, but also to the basic design of the new test machine. At one point, we even exceeded the capability of our new machine and had to bring in the manufacturer to repair it. We worked with the manufacturer of the machine to increase the common understanding of the type of measurements that their machines may potentially be used for in the field. In the end, we greatly increased both the efficiency as well as the uncertainty of the calibrations for these particular units.