Printer off with ESP8266 (Homeautomation)

thingiverse

There are several options available to turn your printer off using a relay to cut off the power supply after a print is finished, but all solutions require you to rewire your printer. I was searching for a simple solution that would allow me to turn my printer off after a print with minimal rewiring. This solution only works if you already have a home automation system in place. I am using ioBroker, but FHEM, openHAB, HASS, and other systems should work as well. To implement this solution, you will need the following components: - A WiFi power switch connected to your home automation system (I used Gosung SP1 flashed with Tasmota) - An ESP8266 module (I used a Wemos D1 mini) - 2 resistors for a voltage divider - Small wire, connector, and PCB to layout the circuit - A modified Marlin version I used a Wemos D1 mini, flashed it with Tasmota, and powered it with the 5V of my MKS Gen L (Ramps also works fine). I then connected Pin 4 of the Servo1 Port of the MKS Gen L to the input D4 on Wemos. However, you need to be careful as the digital Pins of MKS Gen L or Ramps boards are also giving 5V and may not be safe for the ESP/Wemos. Therefore, I connected the pin with a voltage divider to make ~3.3V out of the 5V. You can use 1k ohms plus 2.2 k ohms. I printed a nice enclosure for my Wemos circuit, made a connection cable, and connected it to MKS Gen L on the D4 port together with VCC and GND. Marlin needs to be modified to use the PS_on Pin as Pin 4. So after a print in your slicer, you need to modify the end script and add "M81" as the last command to close the printer. The PS_on Pin is set up in pin_ramps.h. In my home automation system ioBroker, I created a small script that triggers when the state of the switch from Wemos D1 changes to power off. Then, the WiFi switch switches off the complete printer with a 6-minute delay to keep the printer cool down while the fans are still running. Feel free to ask any questions in the comments.