DHT is a combined pack of temperature and humidity sensors. These sensors are ideal for hobbyists who just want to do some data logging. DHT11 sensors are slow in terms of retrieving data. As it is a combined pack, it contains a resistive thermal sensor (a thermistor) and capacitive humidity sensor. A thermistor changes its resistance value depending on the changes in temperature. Technically, all resistors act as thermistors because they dissipate heat when the current is passed through them and are responsible for power losses. However, a resistor's characteristic is that when they are heated up from the external source, the resistance values changes a little bit, which is not so effective to be measured. But this is not the case with the thermistor; its resistance values change in terms of several hundred ohms when there is a slight change in the ambient temperature. A DHT11 temperature sensor provides accuracy near to 2 degree Celsius in the...
Raspberry Pi Sensors
By :
Raspberry Pi Sensors
By:
Overview of this book
Table of Contents (16 chapters)
Raspberry Pi Sensors
Credits
About the Author
Acknowledgements
About the Reviewers
www.PacktPub.com
Preface
Free Chapter
Meeting Your Buddy – the Raspberry Pi
Meeting the World of Electronics
Measuring Distance Using Ultrasonic Sensors
Monitoring the Atmosphere Using Sensors
Using an ADC to Interface any Analog Sensor with the Raspberry Pi
Uploading Data Online – Spreadsheets, Mobile, and E-mails
Creating an Image Sensor Using a Camera and OpenCV
Shopping List
Index
Customer Reviews