Length measurement on roll-fed material and piece goods

Determining the velocity provides the basis for measuring the length. The length is calculated based on the velocity profile while the measured object passes through the measuring location. A laser surface velocimeter (LSV) independently recognizes whether the material is in the measuring location and can start/stop the length measurement accordingly. To achieve maximum measurement accuracy the LSV offers you the option of connecting light barriers as a means of starting or stopping the length measurement. This means you can link up several light barriers with one another to obtain a variety of application options. This may include, for example, controlling the length measurement using both trigger inputs, thereby increasing accuracy

Laser surface velocimeters (LSVs) from Polytec are ideally suited because they can conduct measurements on almost any surface and they are not susceptible to contaminated surfaces. The non-contact measuring technique makes it possible to eliminate any negative influences on accuracy, such as slippage and wear, simultaneously. The product being subjected to the measurement also remains intact. Another benefit of Polytec systems is the flexible interface concept – it enables length readings via encoder output, serial interfaces, LAN, Profibus and Profinet.

Length measurement

Polytec LSVs are used for a variety of length measurement processes in the wood and construction materials industry:

  • in the winding of sheet materials
  • monitoring cut lengths, e.g. on fiber cement, plasterboard, wood and wood products, glass wool, mineral wool and roofing material

Industrial length and speed control with optical sensors