for Battery Energy Storage Systems
As an alternative to fixed-contact power rails and busbars, backplanes with spring contacts enable individual testing and replacement of a battery’s cells. Dimensional accuracy and spring characteristics are critical to the quality of such contacts, so 100 % checking has to be carried out on each contact terminal.
By means of an automatic X/Y positioning unit, each spring contact is positioned under an electrical linear actuator with a 8431/32 strain gage force sensor mounted on the front end, and a test stroke is initiated orthogonally to the spring contact. Depending on the design of the spring contact, a test stroke of typically only < 1 mm compression is performed within the permissible elastic spring deflection. The DIGIFORCE® 9307/9311 process monitoring can record the quality-relevant parameters of initial height h0, spring rate and hysteresis, and check them for compliance with tolerance specifications. An OK/NOK evaluation and measured values for reporting are made available at various interfaces.