LJC34A4 Unshielded capacitive proximity switch with NPN /PNP output

The sensing surface of a capacitive proximity switch is composed of two coaxial metal electrodes, which act like the electrodes of a non-linear capacitor and are connected in series within an RC oscillation circuit. When no object is nearby, the RC oscillator does not oscillate. When an object approaches the electrodes, the dielectric constant between the object and the electrodes changes, causing the capacitance to increase and the oscillator to start oscillating. Through subsequent circuitry, the signals of oscillation and non-oscillation are converted into a switch signal, thereby detecting the presence or absence of an object.

1.Wide detection range, capable of identifying metals, plastics, glass, paper, liquids, and almost all other materials.
2.Non-contact triggering, no mechanical wear, long service life, suitable for high-frequency work scenarios.
3.Fast response speed, can quickly capture the approach or departure of target objects, compatible with high-speed moving equipment.
4.Detection is unaffected by the color or surface roughness of the target object, offering strong stability.
5.Some models feature waterproof, dustproof, and anti-interference designs, suitable for use in harsh environments such as humidity, dust, and electromagnetic interference.

1. Liquid Level and Material Level Detection: Water tank/oil tank liquid levels; powder/granular material levels
2. Packaging and Filling Industry: Bottle cap detection; label detection; filling control
3. Non-metal Object Counting: Detect the passage of wooden boards, cartons, plastic bags, and rubber parts on a conveyor belt.
4. Paper Detection: Detect whether paper is in place or missing in printers or packaging machines.
5. Humid/Dirty Environments: Compared to photoelectric switches, capacitive switches are less affected by water vapor, oil, and dust (as long as the entire sensing surface is not covered, which would cause sensitivity drift).