Sensing Through Dust for Material Handling

The Application

A customer was using several competitors’ photoelectric sensors in their packaging and material handling system. They were packing raw bulk products such as soil, cement, and dog food into a variety of containers. There is often dust and debris in these environments that settle onto the sensors, even along the long conveyor systems.

The Goal

They desired a photoelectric solution using a variety of modes in the same enclosure.  A common enclosure allows the use of a standardized mounting bracket, saving time in assembly and installation.

The Solution

The Series 28 offers diffuse mode with background suppression to 2 meters, diffuse mode with background suppression in laser, retroreflective mode, retro-reflective zone scanner, and through-beam mode.  All in the same surrounding enclosure that would use the same mounting hardware the customer makes.

They started purchasing the various sensing modes five years ago and have added several ultrasonic sensors for load measuring.  Up until two years ago, they were still hardwiring the controls on the conveyor systems.  These conveyors are an average of 70 feet but can be as long as 160 feet. We discussed using junction blocks and extension cables to save labor and hardware costs of the conveyor systems. After their first conveyor system installation using Pepperl+Fuchs junction blocks and extension cables, they made this their standard. 

The retroreflective and through-beam modes provide extra power to the LED so that the light can see through the dust that collects on the lens.