# Width measurement and monitoring for cotton bale bag manufacturing using contrast sensing > Customer seeking a specialized web width measurement system using contrast sensing. Converting line that manufactures bags for bales of cotton. In the process they coated a web of interlaced extruded green PET material. This coating was clear and extended past the edge of the PET material. The excess coating would then be trimmed off. The customers problem was that the final product, cotton bale bags, depended on the trimmed material. The bags had to fit over a cotton gin/baler. Material width out of specification would result in bags that would not fit the cotton gin/baler and cause problems to our customer's clients. **Last updated:** 2025-12-29 **Source:** https://r2r.tech/testimonials/width-measurement-and-monitoring-cotton-bale-bag-manufacturing-using-contrast-sensing --- Our sales representative for the South East US region contacted us about a multinational company in NC with a web width measurement and monitoring issue. **This manufacturer of multiple transit packaging solutions (strapping, stretch and protective packaging) was interested in our technology as they could not find a solution to their problem.** One of their converting lines manufactures bags that hold bales of cotton. In the process they coated a web of interlaced extruded green PET material. This coating was clear and extended past the edge of the PET material. The excess coating would then be trimmed off. The customers problem was that the the final product, cotton bale bags, depended on the trimmed material. The bags had to fit over a cotton gin/baler. Material width out of specification would result in bags that would not fit the cotton gin/baler and cause problems to our customer's clients. Variations in width would occur from necking of the web due to tension, extruder speed, extruder variations, and other lesser conditions. They wanted to have a system that could constantly measure the web width, typically between 46.75 inches and 49.25 inches. The system should allow them to identify material that falls out of this range by measuring the web and when out of range fire a 12V signal to a spray marking system. This would help the operators in the process to identify and remove these bags so they will not be a quality issue. The line had initially come with a web width measuring that they had removed and set aside because it did not provide them with a solution for their problem. ![Original Measurement System uninstalled](https://r2r.tech/sites/default/files/inline-images/Measurement%20system%20taken%20down%20from%20line.JPG) The solution proposed to the customer was a [SCU5 controller](https://r2r.tech/products/roll-2-roll-controller) with Ethernet communications, a RTI PLC and two [WPS 221 WL](https://r2r.tech/products/wps-221) (white light) sensors for contrast sensing. The proposed solution provided the necessary requirements for monitoring the web width and marking sections where the width was out of specifications. ![Width measurement system with contrast sensors](https://r2r.tech/sites/default/files/inline-images/IMG_5887.JPG) ![Width measurement system with contrast sensors](https://r2r.tech/sites/default/files/inline-images/Width%20measurement%20with%20contrast.JPG) Additionally, the system recorded the measurements on intervals requested by the customer. **You can see a video of the application at work [here](https://r2r.tech/videos/web-width-measurement-and-monitoring-system).** During a customer visit in the region a team of sales reps visited the customer to go through the operating process with the customer and consulted with the Roll-2-Roll Technologies engineering team for some additional applications required. The system has been in operation since then to the satisfaction of the customer. ## Related Products - SCU5 - WPS 221 **Tags:** SCU5, WPS 221 --- ## About Roll-2-Roll Technologies Roll-2-Roll Technologies LLC, headquartered in Stillwater, Oklahoma, manufactures patented fiber-optic web position sensors and web guiding systems for roll-to-roll manufacturing. Products include ODC edge sensors (48mm to 960mm), 1DC all-in-one sensors, SCU-series controllers, and complete web guide systems. - Website: https://r2r.tech - Phone: +1 (888) 290-3215 - Email: sales@r2r.tech