OctoShield

This Raspberry pi hat can be used with OctoPrint-Enclosure plugin.

This hat is compatible with Raspberry Pi 2, 3 or 4.

With this hat, you will be able to:

• manage a 30x30 5V fan to regulate the Raspberry Pi temperature
• manage a dual relay module for printer power and a LED strip
• read the temperature of your enclosure with a DS18B20 sensor
• cut the power of your printer when some smoke is detected by an external smoke detector or when you press an emergency button

All connectors are JST XH to be easier to use.

Inputs / Outputs

• GPIO.5 (Output): The fan
• GPIO.7 (Input): The DS18B20 sensor
• GPIO.27 (Input): The power button to toggle printer power
• GPIO.17 (Output): The signal to the relay which manages the printer power
• GPIO.4 (Input): The LED button to toggle LED strip power
• GPIO.3 (Output): The signal to the relay which manages the LED strip power
• GPIO. 6 (Input): The emergency signal to turn off the printer power

Power

The board works with a 5V DC power. The power supply must be connected to J1 connector:

Fan

The fan must be connected to J3 connector:

The fan can be controlled with the GPIO.5. A HIGH level turn on the fan.

You can use the provided script and SystemD service to manage the regulate the temperature.

You must use the SSH access to enable the service by executing following commands with the pi user:

git clone https://github.com/rclsilver/octoshield.git
sudo cp octoshield/fan-control/fan-control.py /usr/local/bin
sudo cp octoshield/fan-control/fan-control.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable fan-control.service
sudo systemctl start fan-control.service

Temperature sensor

The sensor must be connected to J4 connector:

Temperature sensor DS18B20 can be used with the 1-Wire protocol on a Raspberry Pi.

You must enable this interface to be used with the SSH access by executing following commands with the pi user:

sudo raspi-config

Note: Use the direction arrows to navigate in the menu and the Enter key to validate.

1. Enter in the Interfacing Options menu

2. Enter in the 1-Wire submenu

3. Select Yes and press the Enter key

4. The interface has been enabled, you can press Enter to continue

5. You can now select Finish with the Right arrow key

6. You have to reboot the Raspberry pi

You will need to obtain your temperature device id by executing the following command:

cat /sys/devices/w1_bus_master1/*/name

This will print the ID if all is working fine. If nothing is printed, please check your installation.

Now, in the OctoPrint-Enclosure plugin settings, you can add your sensor by adding a new Input and following this screenshot:

Printer power

The power switch must be connected to J5 connector:

When +5V and IN pins are connected, a LOW level is transmitted to the PWR pin of J9 and power of printer is turned on. In this case, OUT pin is powered by a 5V DC power to turn on a light signal.

OctoPrint

Now, in the OctoPrint-Enclosure plugin settings, you can manage the printer power relay following those screenshots.

Input

Output

LED strip power

The LED strip switch must be connected to J8 connector:

When +5V and IN pins are connected, a LOW level is transmitted to the LED pin of J9 and power of LED strip is turned on. In this case, OUT pin is powered by a 5V DC power to turn on a light signal.

OctoPrint

Now, in the OctoPrint-Enclosure plugin settings, you can manage the LED strip power relay following those screenshots.

Input

Output

Smoke detector / Emergency button

You can use both a smoke detector or an emergency button to power down the printer.

Smoke detector

Most of detectors send 9V DC power when it detects some smoke. You must find points on your and connect them on J8 connector:

When the detector is detecting smoke, a HIGH level is transmitted to the GPIO.6. You have to tell OctoPrint to turn off the printer.

Emergency button

The emergency button must be connected to J7 connector:

When +5V and IN pins are connected, a HIGH level is transmitted to the GPIO.6. You have to tell OctoPrint to turn off the printer.

OctoPrint

Now, in the OctoPrint-Enclosure plugin settings, you can add your emergency input following this screenshot.