Checking your electronic hopper or tank scale's accuracy
Weighing accuracy in processing and handling operations has always been vital to controlling product quality and production costs. Now, emerging ISO 9000 quality standards are making weighing accuracy even more important. The standards will apply to every scale in your operation, including in-plant process control scales -- like electronic large-capacity hopper or tank scales -- that traditionally haven't required the testing and inspection other scales require. To help you prepare for ISO 9000 quality standards, this article explains what can go wrong with a hopper or tank scale and cause inaccurate weighing, then discusses quick, accurate, and affordable ways to test the scale's weighing accuracy. Related information discusses how ISO 9000 quality standards will affect your weighing operation.
True or false? Your electronic hopper or tank scale is displaying accurate weight as long as the displayed weight is stable, rather than bouncing around. False. If the scale has three load cells and one has failed or drifted out of tolerance, the displayed weight -- however stable -- can be off by 33 percent.