Creep adjustment

Spring-element material exhibits positive creep when it is loaded (elasticafter-effect). Strain gages show a negative creep under load. The signal of a loaded transducer is the sum of both the opposite effects. For high accuracy transducers, the strain gage creep has to be matched as closely as possible to the creep of the spring material. Creep behaviour depends on many parameters such as spring material,strain field, type and thickness of adhesive, strain gage material and design.The end-tab ratio is one of many parameters affecting creep. Most HBM strain gages are available in different end-tab ratios. The effect of different end-tab ratios on creep has to be evaluated experimentally, keeping all other parameters constant. The strain-gage end-loop length ”u” corresponds to a multiple of the gridline width ”s”.End-loop ratios are commonly coded as a letter of the alphabet or, directly, as the relationship between loop length and grid-line width. The table below shows the relationship between both coding systems.