Capacitive sensors - System description

  • High noise immunity guarantees high operational reliability.
  • Sensing range adjustable by means of a potentiometer or pushbuttons.
  • Plastic or metal housings for different applications.
  • Sensors for position and level detection.
  • Mounting accessories for installation on tanks or sight glasses (bybass).

Capacitive sensors
Capacitive sensors are used for the non-contact detection of any objects and for level monitoring. In contrast to inductive sensors, which only detect metallic objects, capacitive sensors can also detect non-metallic materials. Typical applications are in the wood, paper, glass, plastic, food and chemical industries. In packaging systems, capacitive sensors might check the presence of cardboard boxes, or monitor the level of a medium in a carton (e.g. milk carton). Another example is the detection of sheets of glass or wood panels on a roller conveyor.

Operating principle
The capacitance between the active electrode of the sensor and the electrical earth potential is measured. An approaching object influences the oscillating field between these two capacitor plates and, consequently, the capacitance. This applies to metallic and non-metallic objects. The potentiometer or pushbutton allows the user to set the sensitivity.

More information

System overview — Capacitive sensorsSelector — Capacitive sensorsProduct Innovations — Capacitive sensors

Capacitive sensor | ifm
Not only metal: Capacitive sensors detect almost all materials, here for example a log in a saw mill.