CPU FAN RPM MEASUREMENT WITH HALL EFFECT SENSOR 09/11/2016 Aim/Introduction Magnetic sensors are solid state devices that are becoming more and more popular because they can be used in many different types of application such as sensing position, velocity or directional movement. Our project consists of one of those application namely RPM measurement of a CPU fan. Also the slightest changes in circuit and programming will result into displaying different applications hence this project can be a viewed as a standard one for Hall-effect applications. Normally the hall-sensor is attached inside the cpu fan but we have done this project by using hall-effect sensor externally and built external circuit for that in order to better understand its working principle and applications. Theory/Principle Hall Effect occurs when a current passing through a conductor in the presence of a transverse magnetic field produces an asymmetric distribution of charge resulting in a transverse electric field. Figure 2: Your caption to go here Procedure Connecting the Basic hall-sensor circuit and testing it with Arduino Due by using PC. Building the controller circuit of 1602 LCD display and installing it on the breadboard. Building the mutual connection of LCD display and hall-effect sensor with Arduino Due. Building the magnetic CPU fan system and giving it a 12V DC power supply . Installing library of 1602 LCD display and Arduino software. Writing Code for Arduino Due and LCD display and making digital input-output connection to Arduino and LCD display. Running the Set-up and doing required measurement. Figure 3: Your caption to go here Quisque viverra lectus ac lectus Result Our system is working fine and it measures the CPU fan RPM under various ranges. We have plotted the graph and taken data for fan RPM with time under a random experiment as an example. LCD is displaying the result as expected along with input name provided.

CPU FAN RPM MEASUREMENT WITH HALL EFFECT SENSOR 09/11/2016 What next ? Hall-Effect Sensor can also be used for the Characterization and Detection of Magnetic Nanoparticles for Biomedical Applications but that would be more complex and require advanced technique. The next one is quantum Hall effect (QHE) which is a phenomenon visible in Hall effect measurements on a two-dimensional electron gas in strong magnetic fields and at low temperatures and can be applied in metrology. Figure 2: Your caption to go here Conclusion The Arduino Due board is a very useful tool which converts raw data to a useful output. But, one precaution must be taken for Arduino due as it has 3.3V tolerant pins. If higher than 3.3V is given to any pin of due, it will damage that pin or probably entire board. The maximum value of RPM of the CPU fan is in the range of 1200 to 1400 but the actual maximum value of RPM of a CPU fan is about 3000, this is due to the fact that we have attached magnets on a blade of the CPU fan which reduces the maximum speed of the CPU fan by almost a factor of 3. The constant blinking of the red light insures that our system is working just fine. Figure 3: Your caption to go here Quisque viverra lectus ac lectus References: American journal of Physics www.berkeley.edu www.arduino.cc https://en.wikipedia.org/ .