Емкостные датчики

In our offer of industrial sensors, we're offering, among others, DOL 20R series capacitive sensors. 

DOL 20R capacitive sensor is intended for general detecting of solid and loose materials. This sensor is equipped with a potential-free relay and is intended for use as a switch, also useful in other industrial and agricultural applications.

Applications of capacitive sensors:

• Level control in hoppers, pans, silos, and containers.
• Control of poultry feeding lines
• Detecting levels exceeding liquids and loose materials.
• Detecting objects such as transport on production lines.
• Thickness measurements of wood or foil.
• Detecting dialectics.
• As low-tenacity liquid control sensors; control of liquid occurrence/level in thin-wall containers.
• Detecting metal objects.
• As an alternative for induction sensors.
• For controlling level/existence of aggressive substances.
• Detecting bottle fullness level; paper continuity; the existence of liquids in non-metal tubes; the existence of paper on the stack. 

Capacity sensors - the principle of operation

They generate an output signal when any type of material (wood, metal, plastic, loose products) enters a space of their detection without direct contact. They're especially useful in applications, where inductive sensors cannot be used e.g. because of detecting non-metal objects - capacity sensors are able to detect basically every type of material e.g. metals, liquids, granulated products, wood, paper, glass, grains. 

Their operation principle is based on precise measurement of the condensator capacity depending on the distance between its sidings, which are a sensor and a detected object. The oscillator with two flat electrodes awakens and creates vibrations, while the located in the range of the engine's detection object appears at a smaller distance than a given limit value. Capacity sensors can be powered by AC or DC.

Benefits of capacity sensors:

• high resistance to electromagnetic disruptions; 
• resistance to damage and errors;
• possibility of work in conditions impossible for inductive sensors;
• possibility of AC or DC power supply;
• low price.

Disadvantages: low resistance to contamination and air humidity.