The Whadda inductive proximity sensor detection switch accurately detects metal objects that are within 4 mm of the sensor head. When a metal object is detected, the built-in red LED lights up and the black signal wire is internally shorted to ground through an NPN transistor. When no object is detected, the signal is floating/high impedance. Note: It is recommended to supply the sensor with no more than 6 V, and to put a series protection resistor between the signal output of the sensor and digital input of your board when connected to 5 V logic, such as Arduino® compatible boards.
Features:

1. detects metal objects within 4 mm of the sensor head
2. metal detected:
   1. built-in red LED lights up
   2. the black signal wire is internally shorted to ground through an NPN transistor
3. no metal detected:
   1. signal is floating/high impedance
4. easy connection

Specifications:

1. supply voltage: 6 - 36 V DC
2. sensor model: LJ12A3-4-Z / BX
3. detection distance: 4 mm
4. output signal: NPN (high impedance when no object is present, or ground when object is detected)
5. cable length: ± 110 cm
6. weight: 44 g

manual_wpse476.pdf

ce_rohs_open.pdf