RN 3004 with option separate housing in gravel

The Challenge

A plant builder in Estonia asked for a level switch in a gravel hopper. The function should be a demand detector to set an alarm in time if the hopper gets empty and more material should be filled in. The hopper is equiped with an electrical rotary vibrator. It is mounted at the cone wall. It avoids material deposit the the wall inside and improve the material flow. The vibrator works in short bursts. The hopper is top loaded with a front loader. The material is gravel with 0-32mm grain size. The hopper is located outside therefore the sensor must have a temperature working range from -20° to +30°C. The challenge for the sensor is the strong mechanical load to the electronic housing by the vibrator and to the extension probe inside the hopper by the gravel.

Our Solution

The solution was a rotating paddle switch Rotonivo RN 3004 with the option for a separate housing. It is mechanically uncoupled to the process. A rubber plate devides the shaft and damps the swinging amplitude and protects the gear and the electronic parts against damage. The protection tube at the probe protects in the application. So the gravel cannot damage the sensor and cause a malfunction. The solution is simply working and solves this heavy application.