Abstract
Computer-controlled data-acquisition systems are being used extensively for gathering strain-gage data. This paper explores the relative merits of using modern solidstate digital multi-meters (DDM) to measure the strain-gage resistance directly rather than using a conventional Wheatstone bridge. Both a direct-resistance measurement scheme and a reversed current scheme are compared over long measurements terms of 6 and 12 days using a 6 1/2-digit multimeter. The results show that the reversed current method is superior in maintaining the zero-gage resistance reading at the cost of using several meters. Possibly the direct-resistance method can be improved so that the operation and equipment can be simplified.
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Cappa, P., McConnell, K.G. & Zachary, L.W. Zero-shift values of automatic and inexpensive strain-gage instrumentation systems. Experimental Mechanics 31, 88–92 (1991). https://doi.org/10.1007/BF02325730
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DOI: https://doi.org/10.1007/BF02325730