Coffee Machine Low Water Alert - No Soldering or Coding Needed

Have you ever been frustrated realizing your expensive coffee machine stopped dispensing coffee in the middle of a perfect coffee brewing ?

Hearing the pump screaming and shaking, begging for water is a heart breaker for me (and thinking of the mechanical impacts made it worse)…

So I decided to create my own easy DIY, non-contact and visual sensor that reminds me to fill up the water tank when the water level gets too low.

I'm not a expert in soldering and electronic stuff in general so if I was able to do it, you can do it!

The whole project consists of only a few inexpensive parts plugged all together. It can be made for ~$10.00 (no Arduino/Raspberry, no programming, soldering is optional but recommended).

Part 1: USB Led Strip

Ref: any cheap 5V led strip (size and color you like)

Vendor: Aliexpress

Cost: 4$

Part 2: Water Level Sensor

Ref: XKC-Y25-NPN

Vendor: Aliexpress

Cost: 6$

Part 3: Led Controller

Vendor: Aliexpress

Cost: $2

Note: the led controller is optional (but cool blinking & fading effect)

You just have to do the wiring as described in the diagrams (pick blinking or no blinking mode).

You can see in the photo (blinking mode) that the wiring is basic (better to solder but you can tape it if you don't have skills and tools).

The idea is to place the led strip under the tank (usually there is a cavity) and use thin wires so you don't have to drill any holes in it!

Then just tape (double sided tape ) the sensor at the lowest level you want to be alerted.

We want the led strip to turn on when the tank is almost empty and turn off when the tank is full.

The sensor has an internal NPN transistor, connecting the No/Nc mode wire to the ground will make it Normally Open (no water, signal is LOW, transistor is opened so the output current go through the leds).

The transistor has a max current output of 100mA so it's more than enough to drive 3 leds !