What Is a Check Scale?

A check scale is a scale that can check weights automatically on a packaging or assembly line for quality control and management of the line. This device can operate independently without a technician to control it, and it increases the speed and automation of the line. Many companies manufacture check scales for the industrial production of a wide variety of things. Used or leased equipment might be available for a facility that wants to use a check scale but does not want to invest in buying a brand new model.

The check scale has an incoming conveyor belt that moves packages for weighing, shifting them onto the weight belt. The scale typically takes weights very quickly, with only a momentary pause needed to weigh each package. Based on the weight, the machine can decide whether to route the package to a reject belt because it is the wrong weight or to another conveyor so it can go out for delivery. Underweight and overweight items can be manually inspected by employees.

Check scales typically have a variety of programs that can be set for maximum flexibility and usability. Technicians can set the tare to get an accurate weight on just the contents of packages, rather than the weight of a package and its contents. They also can set the tolerances. For something such as a package of pills, the weight tolerances are very narrow, because each package should contain an exact number of pills, which should always weigh the same. For cartons of fruit, those tolerances might be wider.

It is possible to enter records into the memory of a check scale and to switch back and forth between different programmed weights. This allows operators to use a check scale on the production of numerous products, not just one. It also can adjust the programs if new packaging necessitates a change to the tare weight, or if it changes package designs; for example, a sugar company might transition from from 5-pound (2.27-kg) bags to 4-pound (1.81-kg) bags and would need to adjust its check scale to reflect this change. The scale might record data and offer a moving average on package weights.

Such devices are part of an interconnected network of systems that can automate procedures on an assembly line. This can improve quality control, because the scale is less prone to error than a human operator. It also can increase safety by keeping human operators out of areas that have moving parts and might increase the scale of production by allowing the company to make more, because it has increased its processing capacity as a result of automation.