28-01-2011, 12:27 PM
[attachment=8506]
Submitted by
ALVASIM P. A.
ANUMOL R.
GEO JOY
NIMMY YESUDAS
PRADEEP K. VIJAYAN
MET’S SCHOOL OF ENGINEERING
MALA, THRISSUR DISTRICT
ABSTRACT
Remote controlled Fan Regulator is one of the applications of electronics to increase the facilities of life. Fan is one of the unavoidable Electronic equipment in our day today life. It has become essential element without which people can’t lead a smooth life. The presence of a fan in a house or office is not now considered as a luxury on the other hand it is included in the basic requirement. The uses of new electronic theories have been put down by expertise to increase the facilities given by the existing appliance. Here the facility of ordinary fan is increased by the making it controlled by a remote.
In remote controlled fan regulator we can regulate the speed of the fan by using a remote. Here the variation in the firing angle of triac is used for regulating the speed.
Any button on the remote can be used for controlling speed of the fan. Using this circuit, we can change the speed of the fan from our couch or bed. This circuit is used for controlling the speed of the fan in 5 levels. This innovation can be a success only if people are made aware about its advantages and how user-friendly it is. The circuit can be used to regulate the intensity of light. This innovation finds its use mainly to help old age people who don’t want to walk in order to control the speed of fan. It also finds its use of somebody wants to change the speed while sleeping.
INTRODUCTION
A circuit that allows total control over your equipments without having to move around is a revolutionary concept. Total control over the speed of the fan is a boon to many. This product brings to you this very concept.
Remote control facilitates the operation of fan regulators around the home or office from a distance. It provides a system that is simple to understand and also to operate, a system that would be cheap and affordable, a reliable and easy to maintain system of remote control and durable system irrespective of usage. It adds more comfort to everyday living by removing the inconvenience of having to move around to operate a fan regulator. The system seeks to develop a system that is cost effective while not undermining the need for efficient working.
The first remote control, called “lazy bones” was developed in 1950 by Zenith Electronics Corporation (then known as Zenith Radio Corporation). The device was developed quickly, and it was called “Zenith space command”, the remote went into production in the fall of 1956, becoming the first practical wireless remote control device. Today, remote control is a standard on electronic products, including VCRs, cable and satellite boxes, digital video disc players and home audio players. In the year 2000, more than 99 percent of all TV set and 100 percent of all VCR and DVD players sold are equipped with remote controls. The average individual these days probably picks up a remote control at least once or twice a day.
Basically, a remote control works in the following manner. A button is pressed. This completes a specific connection which produces a Morse code line signal specific to that button. The transistor amplifies the signal and sends it to the LED which translates the signal into infrared light. The sensor on the appliance detects the infrared light and reacts appropriately.
The remote control’s function is to wait for the user to press a key and then translate that into infrared light signals that are received by the receiving appliance. The carrier frequency of such infrared signals is typically around 36kHz.
The aim of this work is to design and construct a remote control for a fan regulator. The remote control device sends an infra-red beam, which is received by the infra-red sensor on the regulator and the speed of the fan is increased.
One of the primary objectives of an engineer is to endeavor to deliver the best product or the most efficient services at the lowest cost to the end user. The system was found to meet the expected results.
BLOCK DIAGRAM
(please download the attached file for geting this)
BLOCK DIAGRAM DESCRIPTION
Infrared Receiver Module ________________________________________
Infrared receiver module is used for receiving the signals transmitted by the remote control.
Here, TSOP 1738 is used as infrared receiver Module. It is capable of receiving signals up to 38 KHz.
Monostable Multivibrator ________________________________________
A multivibrator is an electronic circuit used to implement a variety of simple two-state systems such as oscillators, timers and flip-flops. A monostable multivibrator, as its name indicates, has a stable state and a quasi-stable state. An external trigger must be applied to change from the stable state to the quasi-stable state.
Here, two NE 555 ICs are wired as monostable multivibrators. The trigger to the first multivibrator is the signals from the infrared receiver module. This multivibrator is used to delay the clock pulse of the decade counter. The second multivibrator is triggered by the opto coupler.
Decade Counter ________________________________________
In digital logic and computing, a counter is a device which stores (and sometimes displays) the number of times a particular event or process has occurred, often in relationship to a clock signal. Decade counter is a counter that counts through 10 states. It is also known as a mod-10 counter.
Here, CD 4017 is used as decade counter. Here actually ten outputs are there from which five are used (Q0 to Q4), Q5 is not used and Q6 is used to reset. The output of monostable multivibrator(IC1) is used to delay the clock pulse of the decade counter.
Transformer________________________________________
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors — the transformer's coils or "windings". Transformer is used here to step down the supply voltage to a level suitable for the low voltage components.
The transformer used here is a 230/(12V-0-12V) step down transformer.
Regulator Section ________________________________________
A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level.
IC 7809 is used here. It is a 9V regulator. It regulates the rectified 12V to 9V. This 9V is supplied to the whole circuit.
Opto Coupler________________________________________
An Opto coupler is used to transmit either analog or digital information from one voltage potential to another while maintaining isolation of potentials. It is used for low voltages.
MCT2E is the opto coupler used here. MCT2E is NPN silicon planar phototransistor optically coupled to a gallium arsenide infrared emitting diode. It is used to trigger the monostable multivibrator(IC3).
Opto Isolator________________________________________
An Opto isolator is used to transmit either analog or digital information from one voltage potential to another while maintaining isolation of the potentials. Its operating voltage is higher than that of an Opto coupler.
Here, MOC3021 is used as opto isolator. It is used to drive the Triac BT136.
Triac BT 136________________________________________
A TRIAC, or TRIode for Alternating Current is an electronic component approximately equivalent to two silicon-controlled rectifiers (SCRs/thyristors) joined in inverse parallel (paralleled but with the polarity reversed) and with their gates connected together. The formal name for a TRIAC is bidirectional triode thyristor. This results in a bidirectional electronic switch which can conduct current in either direction when it is triggered (turned on) and thus doesn't have any polarity. It can be triggered by either a positive or a negative voltage being applied to its gate electrode (with respect to A1, otherwise known as MT1). Once triggered, the device continues to conduct until the current through it drops below a certain threshold value, the holding current, such as at the end of a half-cycle of alternating current (AC) mains power. In addition, applying a trigger pulse at a controllable point in an AC cycle allows one to control the percentage of current that flows through the TRIAC to the load (phase control).
The triac used here is BT136. It is thyristor with a firing angle nearly 45o. A snubber circuit consisting of a resistor and capacitor is used to control the firing angle of Triac. This firing angle determines the speed of the fan.
CIRCUIT DIADGRAM
(download attached file)
WORKING OF THE CIRCUIT
The 230 V from AC mains is stepped down to 12V and Regulated by IC7809, capacitor and Diodes to 9V. This filtered 9V is used for providing supply to the entire circuit. Any button of remote control can be used to control the speed of the fan. The remote control produces infrared rays which is received by the TSOP infrared receives module. The TSOP used here is TSOP 1738. It is capable for receiving signals up to 38 KHZ. The infrared rays are received by the TSOP sensor and its output is given as a trigger to the first monostable multivibrator NE 555 through a LED and Resistor R4.
This NE555 which is wired as Monostable multivibrator is used to delay the clock to decade counter CD 4017. We can directly give the output of TSOP to decade counter, but while doing so all the small pulse or noises may also act as clock to counter and counter starts counting. The decade counter has ten outputs from Q0 to Q9. But here we are using only Q0 to Q4. Q5 is not used and Q6 is used to reset the counter. The output of decade counter is taken through Resistors R5 to R9. The resistor R5 to R9 and capacitor C5 controls the pulse width which is actually determining the speed of the fan. If the Q0 output is high the capacitor C5 is charged through R5, if Q1 is high capacitor C5 is charged through R6 and so on, thereby controlling the speed of the fan accordingly. Here we are controlling the speed of the fan in five levels that is why we are taking five outputs (A0 to Q4).
Another NE 555 is used here which is also wired as monostable multivibrator. This monostable multivibrator is triggered by pulses from opto coupler MCT2E. It is wired as Zero crossing detector. The output from decade counter is given to NE555 and this is given to the transistor BC548. It is given to the Opto isolator MOC 3021. It is used for driving the Triac BT136. Triac is a type of thyristor. Here the resistor R13 (470hm) and capacitor C7 (0.01µF) combination is used as snubber network for the Triac.
The Resistors R5 to R9 and capacitor C5 are used to control the pulse width. When Q0 output is high the pulse width is maximum, when Q1 output is high pulse width is decreased slightly. As the pulse width decreases firing angle of the triac increases and speed of the fan also increases. By using remote control we are actually controlling pulse width, which in turn varies the firing angle of triac, and there by varying the speed of the fan.
COMPONENTS LIST
1. IR Receiver Module - TSOP 1738
2. IC NE555
3. Opto Coupler - IC MCT2E
4. Opto Isolator - IC MOC 3021
5. Voltage Regulator - IC 7809
6. Decade Counter - IC CD4017
7. Transformer – 230/(12V -0-12V)
8. Light Emitting Diode
9. Diodes - IN4148, IN 4007
10. Transistor - BC548
11. Triac - BT136
12. Resistors - 1K, 100K, 330Ω, 47K Ω, 33K, 27K, 20K,
12K, 3.3K, 470 Ω, 5.6 K, 10 K, 47 Ω
13. Capacitors - 0.01 µF /400V, 4.7 µF /16V, 10 µF /16V,
1 µF /16V, 0.22µF, 470 µ /50V
14. Zener Diode - 5.1V
PCB FABRICATION________________________________________
Printed Circuit Boards play a vital role here in determining the overall performance of the electronic equipment. A good PCB design ensures that the noise introduced as a result of component placement and track layout is held within limits while still providing components years of assembly maintenance and performance reliability.
WHERE AND WHY ARE PCB’S USED?
Printed circuits boards are used to route electric signals through copper track which are firmly bonded to an insulating base.
Advantages of PCB over common wiring are:
1. PCB’s are necessary for connecting a large number of electronic components in a very small area with minimum parasitic effects.
2. PCB’s are simulated with mass production with less chance of writing error.
3. Small components are easily mounted.
4. Servicing in simplified.
The base materials used for PCB’s are glass epoxy, epoxy paper, polyester etc. Copper foil used for copper clad is manufactured by the process of electronic deposition.
The properties of copper foil are:
• Thickness………………35μ meter
• Thickness tolerance……+5 μ meter
• Purity of Copper………99.8%
• Resistivity at 20oC…….0.1594
PREPARATION OF SINGLE SIDED PCB
In a single sided PCB the conductor tracks run only on one side of copper clad board. Thus crossing of conductors is not allowed. Base materials are selected according to application. It is mechanically and chemically cleansed. The photo resist is an organic solution which when exposed to light of proper wavelength, changes their solubility in developer but after exposure to light is not soluble. Laminate coating of photo resist is done by
(i) Spray coating
(ii) Dip coating
(iii) Roller coating.
The coated copper clad and laminated film negative is kept in intimate contact with each other.
The assembly is exposed to UV light and is rinsed in the developer tank. Proper developer has to be used for a particular photo resist and then the PCB is dyed in a tray. The dye reveals the flux to be used for a particular photo resist. Then the PCB is dyed in a tray.
LAYOUT
The layout can be done either by hand or by using PCB designing software like ORCAD or PROTEL.
FABRICATION
The required circuit is designed and the layout of the circuit is done on the component side as well as the copper clad side. Spaces are provided for holes to insert the respective components. Etch resistant ink coatings are given on the interconnecting marks.
ETCHING
The copper clad PCB is etched with ferrous chloride solution containing a small amount of Hydro Chloric Acid for increasing activeness of Ferric Chloride in etching. Wherever the varnish coating is there the copper remains. Then it is washed with water and Oxalic Acid.
DRILLING
The required holes of suitable size are drilled using twist drill. Now the Printed Circuit Board(PCB) is complete and ready for soldering.
SOLDERING________________________________________
Soldering is the process of joining of two metals using an alloy solder consisting of Tin and Lead (Sn-Pb). Tin determines the melting whereas the Lead is used to reduce the cost. After the PCB fabrication is done, the various components are arranged at proper locations on the PCB and then the soldering is done. All liquids consist of particles which attract each other. The surface is always trying to shrink and this is because of surface tension. The principle behind soldering is that when liquid particles are brought in contact with the walls of the solid surface, it may happen that the solid attracts the liquid surface. This property is called adhesive property. Care must be taken that the melting point of solder is below that of the metal so that its surface is melted without melting without the metal.
NEED FOR FLUX
During the soldering process the flux acts as a medium for improving the degree of melting. The basic functions of flux are mentioned below:
1. Removes oxide from the surface.
2. Assists the transfer of heat from the source to the joining and provides a liquid cover including air gap.
3. Removal of residue after the completion of the soldering operation.
APPLICATION________________________________________
Remote controlled Fan Regulator is used to control the speed of fan from our bed or couch.
The same circuit finds its use to control the Intensity of light at various levels.
This circuit also finds it use for switching ON and OFF any electronic circuit.
ADVANTAGES________________________________________
This circuit is simple to use and efficient.
It can be assembled with ease.
It is cheap and hence very economic.
It is small in size.
CONCLUSION________________________________________
With the knowledge of new techniques in ‘Electronics’ we are able to make our life more comfortable. One such application of electronics is used in “REMOTE CONTROLLED FAN REGULATOR”.
The same circuit finds its use in many more applications. By this the intensity of light can be controlled using a remote. The intensity of light can be controlled in five levels from off position to maximum intensity possible. So it finds use as a night lamp by keeping the intensity of lamp in low level.
The circuit also finds its use for switching ON and OFF any electronic circuitry. Our normal T.V remote can be used for all these purposes. So it is very useful or a real help to old age and sick people, since they can control the speed from the place where they are sitting.
We feel that our product serves something good to this world and we like to present it before this prosperous world.
REFERENCE________________________________________
electronicsforyou.com
howstuffworks.com
wikipedia.org
Electronics for You Magazine
Electronic Devices and Circuits – J. B.Gupta
Linear Integrated circuits – Gaykwad
