Automatic temperature controlled fan electronics project. The temperature controlled fan circuit will automatically control the speed of fan according to the temperature. The temperature based fan speed control system can be done by using an electronic circuit using an arduino board. Autofan, temperature control this circuit was designed to automatically activate a set of three or four small dc fans to cool a large coolrib for a 10 amp powersupply. Features of arduino based temperature controlled fan. The inlet set temperature was reset by a fuzzy logic based on the transformer operating ratio and the oil outlet temperature. The speed of fan increases with the increase in temperature and vice versa and the temperature sensed by temperature sensor on the lcd. Arduino is at the heart of the circuit as it controls all functions. Temperature controlled fan can be used to control the temperature of devices, rooms, electronic components etc. A closed loop control system consists of an input, a control device, output and feedback. Basic circuit of the lm35 are made to control the fan is either used on amplifier that requires automatic cooling.
It contains a design approach that uses fuzzy logic technique to achieve a controlled temperature output function. Thermistors in single supply temperature sensing circuits. Temperature control system using fuzzy logic technique. The transduced is a diode in the forward polarization regime. Automatic temperature controlled fan using thermistor. A circuit with lm35dz temperature sensor, pic16f877a microcontroller, brush less dc motor and few of electronic components is designed and implemented to. Max31740 ultrasimple fanspeed controller mouser electronics. This change is reflected on the fan speed by regulating the current to the fans motor. The circuit of automatic temperature controlled fan is build around temperature transducer ad590 followed by operational amplifier lm324. A blower was used to control the inlet oil temperature while the oil. The block diagram of the temperature controlled fan using a microcontroller is shown in the above figure. This paper elaborates the design and construction of fan speed to control the temperature. If the temperature drops below 40 deg celsius as per the code.
Automatically control the fan speed by sensing the room temperature. Ad590 is a temperature transducer, change temperature into corresponding voltage. Temperature controlled dc fan using thermistor circuit digest. Sometimes we want to move air for exhaust such as a kitchen fan clearing cooking odors away or to bring in cooler air such as a pc fan to reduce internal. Temperature control circuits and tutorials autofan, automatic temperature control, circuit enables precision control in radiant heating systems, constant temperature circuit, electronic thermostat, heating system thermostat, temperature controlled based on at89cx051, temperature controlled ovens, temperature controller, temperature monitor, temperature programmer uses digital control. This is to certify that the work in the thesis entitled temperature controlled dc fan using microcontroller by ghana shyam soren, bearing roll number 111ee0236, and ram ashish gupta, bearing roll number.
An alarm circuit is also attached to indicate the fan turn on. It uses a few components and easily buys at local markets. Here we describe a simple temperature controlled fan speed 2. The output of transducer is given to pin 2 of ic 2 lm324. Automatic fan speed control according to temperature. Its use on power amplifier circuit above and only requires dc fan. Pwm is a technique by using which we can control voltage. The proposed system is designed to detect the temperature of the room and send that information to the. This fan regulator circuit will automatically control the speed of your fan according to the temperature.
Temperature sensor design guide precision temperature measurement with silicon ic temperature sensors, thermocouples, rtd circuits and thermistors a complete listing of products offered by microchip technology inc. This circuit use an ntc negative temperature coefficientwhich is a thermistor is one in which the zeropower resistance decreases with an increase in temperature. The block diagram of the temperaturecontrolled fan using a microcontroller is shown in the above figure. Conclusion the circuit is very simple and easy to build. Temperature control system lm35 precision youtube, one of my 3rd year microcontroller lab projects was to realize a temperature control system using an 8 bit, 80c51 family chip. From basic sensors based on ic and amplifier opamp is added again to the transistor q1 to drive the fan.
Temperature controlled dc fan electronic circuits and. The circuit was designed using electronic components available in local market to keep. Temperature controlled fan regulator electronic circuits, 33 thoughts on temperature controlled fan regulator siddhu march 12, 2015 at 7. This circuit controls a load in this case a dc brushless fan based on a temperature compared with a setpoint. Set the temperature control dial to the coldest setting.
Ac condenser fan high speed circuit troubleshooting hvac dtcs blown fuse no. Here is a simple circuit to automatically switch on and control a speed of a fan according to the temperature. The controller has been designed and fabricated using the opamp ic 741 and a 1k thermistor as the temperature sensor. Although the temperature range of the thermistor is a little better than the diode or siliconbased temperature sensor. Temperature controlled dc fan using thermistor mini. The temperature sensor output is read by the arduino and the software establishes the desired fan speed for a. Auto temperaturefan mode is an intelligent, closedloop control that optimizes fan speed according to userdefined parameters. The two reference voltage is given to pin 6 and pin 10 through. The circuit is very simple and using only five components. In this mini project, we are going to control the speed of the dc fan automatically as the surrounding temperature changes. The block diagram includes power supply, rst circuit, 8051 microcontrollers, lm35 temperature sensor, 8 bit adc, l293d motor driver, dc motor, 7segment display, ip switches. I already made this circuit but fan runs at high speed all times and its noicey. Also the temperature of the system is measured using sensor.
When these processes need to be optimized, control systems that keep temperature within specified limits or constant are often used. The fan is on when v from vr1 is greater than v from r1 and thermistor. If the temperature exceeds more than 50 deg celsius as per the code, the microcontroller will turn on the relay to start the fan. Motor 12v pc fan is connected between pins 3 and 6 1y and 2y. If u have questions about driving motor with transistor just have a look at this article and watch the video i hope. Arduino based temperature controlled fan engineering.
Temperature sensor design guide microchip technology. The circuit can be used for car engine to reduce the heat. Simple temperature controlled dc fan circuit diagram. In this circuit, the temperature sensor used is an ntc thermistor, i. So if temperature increate the voltage at pin 3 on lm311 will decreated. It is accomplished by the data communications between arduino, lcd, dht11 sensor module and dc fan that is controlled by using pwm. A picaxe 08m2 microcontroller and an hih6030 sensor team up to easily control a ventilation fan using temperature or humidity or both. The fan control characteristics are set using external. My temperature controlled fan circuit has a liquid crystal display connected to the arduino to display the temperature in celsius and fan speed 50255 pwm this controls the duty cycle of the fan which then controls the fan speed. Top 5 electronic project using bc547,555 ic,z44n and relay duration. Automatic fan speed control system using microcontroller. Precise digital temperature controller circuit working and.
This particular one also has a manual switch thrown in. The circuit is using a microcontroller to control the fan according to the temperature variations. Design and development of arduino based automatic fan. Now arduino board is very progressive among all electronic circuits, thus we employed arduino board for fan speed control. Construction of a temperature controlled fan using a. You can use this circuit in many electronic projects, which require a cooling fan. Here is a simple circuit to control kitchen fans by monitoring the ambient temperature. The ratio arms r1 and r2 of the bridge are kept fixed say unity. This circuit will turn onoff 12v dc fan or cpu fan when temperature above normal temperature. The system measure the temperature from the integrated circuit, where it will control the fan according to the setting values in the programming.
Download project code circuit 2 temperature controlled dc. So any of vr1, thermistor, r1 are part of making fan start or stop. This can also be compared to the temperature sensing range of the rtd. Fan control temperature using sensor lm35 electronic circuit. Build a temperature andor humidity controlled fan with a. In this project i have tried to explain how to built temperature controlled fan with an arduino basically i have used transistor in order to drive motor. Working of temperature controlled dc fan using thermistor. Temperature controlled dc fan using microcontroller. With this module you can intelligently control power to most types of electrical device based on the temperature sensed by the included high accuracy ntc temperature sensor. Hello friends, in this post we are going to make one simple mini project which is temperature controlled dc fan using a thermistor. Rest of the circuit is a nontraditional electromagnetic relay driver wired around the popular led driver lm3914 ic2. Temperature controlled fan using 555 and opamp all about. This system is better than analoguethermostat system, which has poor accuracy. The working of the temperature control system project can be explained easily by comparing it with a closed loop control system.
For example, it can use for temperature control of an incubator where maintaining a. Each mode controls the fan speed by changing the duty cycle of a pwm output. Temperaturebased fan control is a necessity in a growing number of systems, both to reduce system noise and to improve fan reliability. In this arduino based project, we are going to control dc fan speed according to the room temperature and show these parameter changes on a 16x2 lcd display. Alternatively, the same circuit can be used for automatic temperature controlled ac power control. After setting the temperature control system to a desired temperature, known as a set point. Doc temperature controlled dc fan using thermistor. Temperature controlled fan regulator circuitautomatic fan. When fan control is augmented by fanspeed monitoring, a speedcontrol loop can be implemented that is independent of manufacturing variances and wear on. Temperature controlled fan with an arduino instructables. In this circuit, pin 3 noninverting terminal of op amp 741 is connected with the potentiometer and pin 2 inverting terminal is connected in between of r2 and rt1 thermistor which is making a voltage divider circuit.
When the temperature increases the base current of q1 bc 547 increases which. The w1209 is an incredibly low cost yet highly functional thermostat controller. Make fan control temperature sensor circuit using thermistor duration. Here is a simple circuit based on two transistors that can be used to control the speed of a 12 v dc fan depending on the temperature. Realtime temperature is displayed on its lcd screen, and you can use it to control the temperature within the preset minimum and maximum range. In fact when forward biased, the forward voltage drop accross a diode has a temperature dependance, in. The key component of this temperature controlled fan circuit is thermistor, which has been used to detect the rise in temperature. Temperature controlled fan using 8051 microcontroller.
Auto temperaturefan mode softwarerpm mode and softwaredcy mode. A digital temperature controller circuit is a precise temperature controller in medical, industrial and home applications. Moreover, the fan speed will increase automatically if the temperature will. A temperature sensor is used to sense the temperature. Digital temperature controller full circuit diagram with. Control circuit and load circuit is isolated using optoisolator 4n35 i. Temperature control circuits electronics tutorial and. It monitors the temperature of an external ntc thermistor and generates a pwm signal that can be used to control the speed of a 2, 3, or 4wire fan. It is built around the renowned precision integrated temperature sensor chip lm35 ic1. General description the max31740 is a sophisticated, yet easytouse fanspeed controller.
You can use this idea in your own laptop or you can make your own ventilator for the hot summer days. Pdf automatic room temperature controlled fan speed. When sensor system gets hot, this will control speed motor fan is highest. Temperature controlled dc fan using atmega8 microcontroller. Lm35 is a precision integratedcircuit whose output voltage is linearly proportional to celsius centigrade temperature.