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The Sensortechnik OBS electro-optical volumetric measurement system for discharge conveyors measures the volume of material being discharged from a conveyor belt with an accuracy of 99.5%, using electro-optical technology and then transmits these measurements, wirelessly to the designated mobile phone via Bluetooth.

Main Advantages: 

  Easy to install: once off assembly can be completed in 2 hours.
-      Easy to calibrate: a once off operation and only takes a few seconds to perform after installation. When the angle of the conveyor belt is changed, such as on mobile equipment, the system does not need to be recalibrated. 


  Reliable: due to the way the volume is calculated (scan material profile + belt speed via inductive switch = volume/m³) an accuracy of 99.5% is guaranteed for various conveyor types (ribbed, very short & metal belts) and applications (wood chips, waste, rock etc). The sensor can also be mounted on all pivoting and foldable conveyor belts.
-      Maintenance free: The sensor is dust and vibration proof with no moving parts and operates without any contact to the material so has no wear. Measurements are not affected by external factors such as heat, cold, sunlight, dust, humidity etc.
-     Accurate Results: Printing is available wirelessly via Bluetooth and is not mounted to the machine. Therefore these devices are not influenced by site conditions such as vibration, temperature and wetness. Portable thermal printers offer the advantage to print immediate reports sorted by client and material.
-     Site Control: OBS system creates the possibility to control your site, it provides an all-over time and production control. RECORD material throughput, stoppages of belt etc; MONITOR via immediate reports & downloadable data; CONTROL proactively control further work stops and time management via data/personal liaison with site staff.

The Optical Belt Scales were designed specifically for difficult or unconventional applications and extraordinary preconditions (like e.g. conveyor belts of mobile plants, or very light materials such as wood chips, and waste) and enables a quantification on all kinds of uncommon conveyor belts. Of course it also works at all other conventional applications like on stationary plants (e.g. the MultiLink-type can also be integrated in a PLC).

The volume measuring systems determine the quantity running over the conveyor belt on crushing and screening plants, wood shredder plants, all kinds of stationary plants, in waste sorting areas and all types of bulk materials such as stones, gravel, cement, asphalt, waste and organic materials like wood chips, sugar beets, etc. All these can be measured accurately on ribbed, swivel-out and flat rubber or metal conveyor belts. 

Cause and Effect:

The various restrictions and issues with installation of conventional scales, which are listed below, lead Sensortechnik to develop the Optical Belt Scale system. 

-   A lot of conveyor belts are too short for the installation of a gravimetric belt scale.
-   Most of the conveyor belts are banana-shaped.
-   On fold-away belts an installation is impossible.
-   Ribbed conveyor belts don’t provide accurate results.
-   The belts are moving laterally and therefore the surface pressure is changing steadily.
-   The inclination angle of the plant is changing very often (gravimetric belt scales only provide accurate results for angles up to 20°).
-   The roller speed of the measuring wheel is changing.
-   The load cells are very sensitive against shocks.
-   The pressure on the load cell is not constant therefore there is also material measured, although there is no material on the belt.
-     Quickly changing temperatures cause different stiffness of the conveyor belt. Gravimetric scales then supply incorrect results
-   Material accumulations or a sagged conveyor belt cause further measurement errors.
-   Varying amounts of material on the belt cause tension fluctuations which does not allow precise measurements.
All of these aforementioned factors will not affect the accuracy of the Optical Belt Scales. Sensortechnik Weighing Scales are available, ex stock, from Screenmasters Australia. Contact us today!

Where traditional belt scales fail optical belt scales are the perfect solution! Conventional belts scales combine the weighted product with the speed of the conveyor belt. Here the flow rate in weight / unit time and weight is detected absolutely. To use this method the following conditions have to apply:…

Belt & Weighing Systems