Control challenge (quantity control – weight or volume)
The control challenge starts from the point the weighing needs to be done, whether it is on the fly or at rest. On the fly means the bottles, cans, and jars are on a conveyor belt and as the containers move along, the weighing is done and, at the same time, they are filled with the product. On the other hand, at rest means that the bottles, cans, and jars are stationary while being filled. In both these cases, there is a need for utilizing a strain gauge or a load cell that provides the signals to the PLC for measuring the weight. In both these cases, the products will always be transported by the conveyor belt. The only difference is whether or not the conveyor belt stops while the filling is in progress. The following figure shows a high-level representation of the filling system and its weighing mechanism:
Figure 6.1 – A filling application using a conveyor-based system for transporting...
