People sometimes confuse conveyor scales with in-motion checkweighers. They are very different instruments with different uses. Here are some comparisons and contrasts.
An in-motion checkweigher looks at singulated units of one product ID at a time, compares the weight of each unit to the acceptable weight range for that product ID, and diverts the units that are outside of the pre-determined acceptable weight parameters that are stored in its controller.
There are many methods available for diverting or rejecting items that are out of tolerance.
An in-motion checkweigher might also be asked to send a signal that would make an adjustment to a system that is feeding product to the checkweigher, based on whether products are trending heavy or light. A filling or portioning system could be told to increase or decrease the weight and/or size of products that it sends down the line.
An in-motion checkweigher can be equipped to accumulate data for statistical analysis of product variations and weight ranges.
In-motion checkweighers are often used for quality control purposes to ensure that customers are not getting less than they are paying for and that the company is not eating up profits by giving away product.
Another common use of in-motion checkweighers is as a counting scale to make sure the right number of certain items are contained in packages, boxes, or cases.
An in-motion checkweigher should have three distant conveyor sections. It should have an in-feed conveyor, a conveyor scale, and an exit conveyor. The exit conveyor will usually have some type of divert or reject mechanism.
A conveyor scale measures the weight of each separately spaced item that is conveyed across it. It can send each weighment to peripheral devices, such as label printers or a host computer system. It does not compare those weights to any stored parameters. A conveyor scale can handle chaotic flows of many different products at a time, as long as those products fall within the conveyor scale’s designed weight capacity.
A conveyor scale can be asked to accumulate information such as the number of items weighed during a period of time and the total weight of those items.
Uses for a conveyor scale can be net weight labeling and measuring production levels.
We make both types of scales and our ability to customize them will make sure that yours is optimized for your application.
Learn more about In-Motion Checkweighers.