Embedded Relay and Fan

Introduction

This project is based on a low voltage relay (model SRD-05VDC-SL-C) and on a 2-pin low-consumption fan powered at 5 volts. We will manage the relay via software in order to turn the fan on/off. For ease we are going to connect these components to the FTDI FT232H device, of which there is a dedicated page on this site - refer to the above page for installation.

Connection

This sensor must be connected to the FTDI FT232H development board. The connection connectors are listed below:

Python code

To manage these components, the presence of the "PyFTDI" library is required. The Python code is the following:

from os import environ
from pyftdi.gpio import GpioAsyncController
import time

try:
    device = GpioAsyncController()
    url = environ.get('FTDI_DEVICE', 'ftdi:///1')
    device.configure(url)
    gpio = device.get_gpio()
    direction = gpio.direction
    gpio.set_direction(0b1, 0b1)
    gpio.write(0b0)
    print("FAN IS OFF")
    time.sleep(2)
    gpio.write(0b1)
    print("FAN IS ON")
    time.sleep(10)
    gpio.write(0b0)
    print("FAN IS OFF")
    gpio.set_direction(0b1, 0b0)
    gpio.write(0b0)

except KeyboardInterrupt:
    # Capture keyboard ^C to exit the program
    print('\nYou terminated the program. The program ends!')