Generic - Pulse counter NORMAL



The ESP8266 module can be used as a general purpose digital pulse counter device for various digital sensors. Think about optical sensors with a digital output. To be used for things like gas, water, electricity, door open/close counters, etc.

In this example we will connect an inductive proximity switch (LJ12A3-4-Z/BX). A LJ12A3-4-Z/BX module can be used in order to detect metal. For example in your water consumption meter (as seen in picture).

  • Inductive proximity sensor

  • Detection distance: 4mm

  • Working voltage range: 10V-30V

  • Dimension: M12x10x55mm


ESP               LJ12A3
GPIO (14)  <-->   Signal (black)

12V        <-->   VCC (brown)
GND        <-->   GND (blue)


You need to use a voltage divider to get the signal level down from 12V to 5V.

The LJ12A3-4-Z/BX-5V way

Just buy the 5V version of the proximity sensor and you are good to go.

The resistor way


The 7805 way

7805 IC specifications:
  • Input voltage range 7-35V

  • Current rating Ic = 1A

  • Output voltage range: Vmax=5.2V, Vmin=4.8V

  • Where to buy: AliExpress ($)



7805 is not very efficient and has drop-out voltage problems. A lot of energy is wasted in the form of heat. Higher the input voltage, less efficient your 7805 will be.




Only task number 1..4 is currently supported for the pulse plugin!

Task settings

  • Device: Name of plugin

  • Name: Name of the task (example name WaterMeter)

  • Enable: Should the task be enabled or not


  • GPIO <– Pulse: Pulse input is generally set to GPIO 14 (D5).

  • Debounce time: Debounce time is generally set to 100.

  • Counter type: In this example the type is set to Delta/Total/Time.

  • Mode type: Pulse input is generally set to Falling

    LOW = count when signal go from not low to low (0.8+V to 0.8-V)

    CHANGE = count on signal being changed, low to high (0.8-V to 2.4+V) or high to low (2.4+V to 0.8-V)

    RISING = count if signal is rising, from low to not low (0.8-V to 0.8+V)

    FALLING = count if signal is falling, from high to not high (2.4+V to 2.4-V)


GPIO 16 (D0) is not compatible with pulse counters.

Data acquisition

  • Send to controller 1..3: Check which controller (if any) you want to publish to. All or no controller can be used.

  • Interval: How often should the task publish its value (5..15 seconds is normal).

Rules examples

On WaterMeter#mL Do
 If [WaterMeter#mL]=0
   Publish,%sysname%/WaterConsumption/status,No water running
   Publish,%sysname%/WaterConsumption/status,Water is being tapped

Where to buy




Link 1 ($) Link 2 ($)


Link 3 ($)


Link 4 ($)

$ = affiliate links which will give us some money to keep this project running, thank you for using those.