YF-S201 Hall-Effect Water Flow Sensor. ... (Yellow) wire of the water flow sensor to Arduino’s digital pin 2. Note that the water flow sensor is not a power-hungry type; it draws a maximum of 15-20mA ...

The device is built around a cheap 1/2″ brass water flow rate sensor connected to his shower hose, which outputs pulses as a small wheel passes an internal hall effect sensor.

The Hall sensors are read by an Arduino Nano, which computes the angles into movement of the pantograph head and records it as G-Code. This can simply be displayed on the attached LCD display, or ...