Rechner Sensors

Capacitive proximity sensors (or switches) are ON/OFF output devices used to detect the presence of an object at a specific distance or the presence of material in front of the sensor.

They can detect the presence of objects through non-conductive containers such as cardboard boxes, and plastic or glass vessels.

While some applications benefit from the sensor being in direct contact with the material (ie, in level applications) it is not always necessary.

Analog versions of capacitive proximity switches will not turn ON or OFF when a specific amount of material is in front of the sensor but will provide a continuously changing reading as more material is moved in front of the sensor or as an object gets closer to the sensor.

They can be used for quality control or for measuring the height of a material. Using them on the side of a plastic/glass container or beside a stack of paper lets you know when you are running out of materials. They can be used for multiple products without having to re-adjust the sensor for different materials. The most common method of implementing this is by creating different profiles for different products in a PLC.

Unlike capacitive proximity sensors, probe level sensors are designed to be in direct contact with the target material. Once the level reaches a specified height, the sensor will switch and produce an electrical signal that can be used to control equipment or sound an alarm. Level applications often have more than one level detection requirement (ie high- and low-level detection) or require continuous level measurement with an analog sensor.

Applications for these sensors are diverse, ranging from small vessels where the height of the material only changes by a fraction of an inch – up to large filling hoppers more than 6 feet tall.