Proximity sensor

A proximity sensor is a sensor able to detect the presence of nearby objects without any physical contact. A proximity sensor often emits an electromagnetic field or a beam of electromagnetic radiation, and looks for changes in the field or return signal.



Due to their reliability and efficiency, inductive proximity switches are used whenever a metal object has to be detected within just a few millimeters:

  • Presence detection of a machine component
  • Ultra precise referencing of the zero position of a moving machine component (e.g. in robotics)
  • Detection of different positions (e.g. limit switches)
  • Counting metal objects (e.g. in component feed or conveyor technology)
  • Presence detection of objects in process
  • Rotary speed measurement on metal gear wheel



  • This is a normally open proximity switch sensor with 10mm detection distance.
  • When proximity switch is close to some target object, it will send out control signal.
  • It is a component widely used in automatic control industry for detecting, controlling, and non-contact switching.
  • High sensitivity, quick response, stable performance.
  • Non-contact detection avoids the sensor and the target object from damages.



Model: LJ30A3-10-Z/BX

Detection distance: 10mm±10%

Setting distance: 0-8mm

Delay distance: <10% of detection distance

Detection object: Magnetic metal(The detection distance decreases when it is non-magnetic metal)

Standard detection object: Iron 30*30*1mm

Response frequency: 0.5kHz

Supply voltage: DC12-24V (6-36V) impulse (P-P) below 10%

Withstand voltage: AC1000V 50/60Hz 1min

Current consumption: N.P type: <13mA, D type: <0.8mA, A type: <1.7mA

Control output: N.P type: <300mA, D type: <200mA, A type: <400mA

Loop protection: N.P.D type: reverse connection protection, surge absorption, load short circuit protection, type A: surge absorption

Ambient temperature and humidity: -30~65, 35-95%RH

Temperature influence: Temperature range -30~65℃, at 23±15% detection distance; Temperature range -25~60, at 23±10% 0detection distance

Insulation impedance: >50MΩ

Housing material: Nickel plated brass

Detection surface: ABS


Project Example

Inductive Proximity sensor Switch DC NPN 3-Wire Normally Open LJ30A3-10-Z/BX