An optimum arrangement of load cells for determining the weight of tanks is achieved when the tank rests on three bearing points and a load cell is positioned on each support. This state is referred to as statically determinate. The overall load should also be distributed as evenly as possible over the three load cells. In the case of upright or suspended cylindrical tanks, the best way to meet this requirement is if the three load cells are arranged at equal distances from the vertical axis of the tank and are offset from each other by 120° on the same plane. Figure 1 defines the arrangement of bearing points for horizontal tanks.
If not all the supports in a system are equipped with load cells, an uneven distribution of the support load is recommended. The supports with load cells should have greater loads than the supports without load cells. Following this guideline can improve the overall accuracy of the weighing device. When designing the system and selecting the load cells, it is preferable for all the load cells to be subject to loads of the same magnitude.