Temperature controlled Fan speed

Project Cost: 5,900

Project Code: 1160

Description of the project:

The temperature controller can be done by using an Electronic circuit, Microprocessor, or microcontroller. Now microcontroller is advanced among all the above circuits therefore we are using a Microcontroller for temperature control. In Temperature controlled Fan speed project, microcontroller 89s51 forms the processing part

The microcontroller first receives data from ADC. ADC receives data from the temperature sensor through an amplifier. Then microcontroller 89s51 performs the comparison of the current temperature and set temperature as per the logic of the program for which the microcontroller has already been programmed. The result obtained from the above operation is given through an output port of 89s51 to LCD display of relevant data and generated pulses as per the logic program which is further fed to the driver circuit to obtain the desired output of the ceiling fan.

Block Diagram:

You will get the following documents with this project:

1. Project Report in pdf format and in doc (word) format
2. Circuit diagram
3. PCB layout
4. Microcontroller program in assembly language
5. Hex file of the microcontroller code
6. Datasheets of all the components / ICs used in the project

Photographs of the Temperature controlled Fan speed project:

Description in detail:

Similar to other sensor based projects for final year, the “Temperature Controlled Fan” is also designed around the micro-controller.

Below are the main blocks of the system:

1. Micro-controller board: It is a low-power, high-performance CMOS 8-bit microcomputer with 4K bytes of Flash Programmable and Erasable Read Only Memory PEROM). The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the MCS-51. Instruction set and pin out. The on chip Flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, it provides a highly flexible and cost effective solution so many embedded control applications.
2. Temperature Sensor: The temperature sensed by using LM 35. The output voltage of LM 35 varies in liner proportion with the temperature. The sensitivity of LM 35 is 10 mV/0C. For 1 0C output of LM35 is 10 mV. For 10 0C output of LM35 is 100 mV.
3. ADC: ADC means analog to digital converter. The output of signal conditioning is in the analog form. But Microprocessor requires input in digital form for this purpose we have to use ADC. In this project we are using ADC 0808. The reference voltage is +5 V. The resolution of ADC is 20 mV. Therefore for 20 mV output of ADC is (01) H. And for 100 mV output of ADC is (05) H.
4. Amplifier: Output signal from micro-controller 89C51 is weak so we have to amplify that signal. Amplifier block amplifies the signal for driving the final control element i.e. output device. For amplification Transistor BC 547 is used.
5. Output Block: In this project we are using FAN as output device. If temperature is above set point then Fan is ON so that temperature will start to decrease
6. LCD Display: In this project we are using 16 X 2 intelligent LCD display to display the college name, temperature set point and very important is temperature of “Temperature Controlled Fan”.
7. Power supply Block: For our project we require + 5 Volt, – 5 Volt and +12 Volts supply. +5 Volts and. 5Volts is given to Micro-controller board, Temperature sensor, Signal conditioning, ADC etc. +12 Volts are used to drive the relay.

Applications and Advantages of Temperature controlled Fan speed:

1. This project can be used at Home.
2. This project can be used in Industry.
3. This will help in saving energy/electricity.

Future Development:

1. We can monitor more parameters like humidity and light. At the same time control them.
2. We can send this data to a remote location using mobile or internet
3. We can draw graphs of variations in these parameters using computer

Video of the project: Temperature controlled Fan speed

Youtube video is coming soon

Questions and answers about this project:

Question: Which type of fan can be controlled using this project? AC or DC?

Answer: We have used Triac to control speed of the fan. So you have to use AC fan. But we can provide DC fan as well if you want. Relay or transistor circuit can be provided to control speed of DC fan. Thus user can use fan operating on 12 volt (CPU fan).

Question: I want to control the Temperature using the Computer, Desktop. Can I get PC-based temperature control?

Answer: In the current project, Temperature monitoring on PC is possible, but it does not have facility of Controlling temperature using computer.

Question: I want to display the temperature in Fahrenheit. Can you use LM34 instead of LM35 to measure Fahrenheit instead of Celsius?

Answer: Yes, we can display temperature in Fahrenheit. We can use LM35 and can use formula to convert temperature from Fahrenheit to Celsius.