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Details:
I have seen a topic called Automatic Room Light Controller here.But i'm aiming to control a Fan too in addition to the light.I'm not using microcontroller in my circuit,since i'm poor in programming. I'm using 2 LDRs at the door to sense entry or leaving people.i got 2 circuits using LDR. One contains 4 quad opamps LM324,logic gates and 2 decade counter CD4017(for counter)as main parts while the other includes NE555 timer too.Igot the former circuit from E4U february 2011 edition.
The temperature controled fan is nothing but a fan connected an NTC Thermister.The output of the thermister is used for controlling the fans speed linearly.The circuit contains Thermister,opamps and Ic MDC 3011 as the main components.The circuit is present in your website.

I dont know how to program the ICs.

Current stage:
I have a plain PIC IC and we have the kit needed for its programming.We have 2 seperate circuits which has to be united. We had presented our abstract and have to start doing the project in this week itself

Problems:
1.Even if i got two circuits for Automatic Room Controller part and one for Temperature Controlled Fan, I Dont know how to merge these two circuits.
2.I am suggested to use PIC IC in my circuit by reducing its size.But i dont know what will be the resulting circuit.

Expectation:
I expect you to give me an equivqlent circuit and the program required for the IC.I am also expecting your valuable suggestions in this project.

Referance:
Electronics for You,February 2011

ABSTRACT


Many times we forget to switch off appliances like lights, fans and air conditioners before leaving house, office, college etc. This leads to considerable wastage of electricity apart from reducing the life of appliance. The circuit contains a counter to count the number of equipments in a room.
The circuit presented here senses the absence of occupants in a
Room and automatically shuts off the power to a particular appliance, say a tube light or fan. It turns on the appliance again when someone enters the room. The circuit uses LDRs as sensors.
Along with the automatic room controller circuit, an extra circuit is provided for automatic temperature controlled fan. Here the speed of the fan can be linearly controlled, depending on the room temperature. Since it uses thyristors in the circuit, it is highly efficient. The circuit use NTC thermister as the temperature sensor.
The project also contains an equivalent circuit which converts temperature to voltage which is used to control a fan and thus we can compare the efficiency of the thermister with the equivalent circuit

ATTACHMENTS:
1.AUTOMATIC TEMPERATURE CONTROLLED FAN
Here is a circuit through which the speed of a fan can be linearly controlled automatically, depending on the room temperature. The circuit is highly efficient as it uses thyristors for power control. Alternatively, the same circuit can be used for automatic temperaturecontrolled AC power control.In this circuit, the temperature sensor used is an NTC thermistor, i.e. one having a negative temperature coefficient. The value of thermistor resistance at 25°C is about 1 kilo-ohm. Op-amp A1 essentially works as I to V (current-to-voltage) converter and converts temperature variations into voltage variations. To amplify the change in voltage due to change in temperature, instrumentation amplifier formed by op-amps A2, A3 and A4 is used. Resistor R2 and zener diode D1 combination is used for generating reference voltage as we want to amplify only change in voltage due to the change in temperature. Op-amp μA741 (IC2) works as a comparator. One input to the comparator is the output from the instrumentation amplifier while the other input is the stepped down, rectified and suitably attenuated sample of AC voltage.This is a negative going pulsating DC voltage. It will be observed that
with increase in temperature, pin 2 of IC2 goes more and more negative and hence the width of the positive going output pulses (at pin 6) increases linearly with the temperature. Thus IC2 functions as a pulse width modulator in this circuit. The output from the comparator is coupled to an optocoupler, which in turn controls the AC power delivered to fan (load).
The circuit has a high sensitivity and the output RMS voltage (across load) can be varied from 120V to 230V (for a temp. range of 22°C to 36°C), and hence wide variations in speed are available. Also note that speed varies linearly and not in steps.Besides, since an optocoupler is used, the control circuit is fully isolated from power circuit, thus providing added safety. Note that for any given temperature the speed of fan (i.e. voltage across load) can be adjusted to a desired value by adjusting potmeters VR1 and VR2 appropriately. Potmeter VR1 should he initially kept in its mid position to realise a gain of approximately 40 from the instrumentation amplifier. It may be subsequently trimmed slightly to obtain linear variation of the fan speed.

2.AUTOMATIC ROOM CONTROLLER
An ordinary automatic room power control circuit has only one light sensor. So when a person enters,the room it gets one pulse and the lights come ‘on.’ When the person goes out it gets another pulse and the lights go ‘off.’ But what happens when two persons enter the room, one after the other? It gets two pulses and the lights remain in ‘off’ state.

The circuit described here overcomes the above-mentioned problem. It has a small memory which enables it to automatically switch ‘on’ and switch ‘off’ the lights in a desired fashion. The circuit uses two LDRs which are placed one after another (separated by a distance of say half a metre) so that they may separately sense a person going into the room or coming out of the room.
Outputs of the two LDR sensors, after processing, are used in conjunction with abicolour LED in such a fashion that when a person gets into the room it emits green light and when a person goes out of the room it emits red light, and vice versa. These outputs are simultaneously applied to two counters.

One of the counters will count as +1,+2, +3 etc when persons are coming into the room and the other will count as -1, -2, -3 etc when persons are going out of the room. These counters make use of Johnson decade counter CD4017 ICs. The next stage comprises two logic ICs which can combine the outputs of the two counters and determine if there is any person still left in the room or not.
Since in the circuit LDRs have been used, care should be taken to protect them from ambient light. If desired, one may use readily available IR sensor modules to replace the LDRs. The sensors are installed in such a way that when a person enters or leaves the room, he intercepts the light falling on them sequentially—one after the other.

When a person enters the room, first he would obstruct the light falling on LDR1, followed by that falling on LDR2. When a person leaves the room it will be the other way round.

In the normal case light keeps falling on both the LDRs, and as such their resistance is low (about 5 kilo-ohms). As a result, pin 2 of both timers (IC1 and IC2), which have been configured as monostable flip-flops, are held near the supply voltage (+9V).

When the light falling on the LDRs is obstructed, their resistance becomes very high and pin 2 voltages drop to near ground potential, thereby triggering the flip-flops. Capacitors across pin 2 and ground have been added to avoid false triggering due to electrical noise.

When a person enters the room, LDR1 is triggered first and it results in triggering of monostable IC1. The short output pulse immediately charges up capacitor C5, forward biasing transistor pair T1-T2. But at this instant the collectors of transistors T1 and T2 are in high impedance state as IC2 pin 3 is at low potential and diode D4 is not conducting.

But when the same person passes LDR2, IC2 monostable flip-flop is triggered. Its pin 3 goes high and this potential is coupled to transistor pair T1-T2 via diode D4. As a result transistor pair T1-T2 conducts because capacitor C5 retains the charge for some time as its discharge time is controlled by resistor R5 (and R7 to an extent). Thus green LED portion of bi-colour LED is lit momentarily.

The same output is also coupled to IC3 for which it acts as a clock. With entry of each person IC3 output (high state) keeps advancing. At this stage transistor pair T3-T4 cannot conduct because output pin 3 of IC1 is no longer positive as its output pulse duration is quite short and hence transistor collectors are in high impedance state.

When persons leave the room, LDR2 is triggered first, followed by LDR1. Since the bottom half portion of circuit is identical to top half, this time, with the departure of each person, red portion of bicolour LED is lit momentarily and output of IC4 advances in the same fashion as in case of IC3.

The outputs of IC3 and those of IC4 (after inversion by inverter gates N1 through N4) are ANDed by AND gates (A1 through A4) and then wire ORed (using diodes D5 through D8). The net effect is that when persons are entering, the output of at least one of the AND gates is high, causing transistor T5 to conduct and energise relay RL1. The bulb connected to the supply via N/O contact of relay RL1 also lights up.

When persons are leaving the room, and till all the persons who entered the room have left, the wired OR output continues to remain high, i.e. the bulb continues to remains ‘on,’ until all persons who entered the room have left.

The maximum number of persons that this circuit can handle is limited to four since on receipt of fifth clock pulse the counters are reset. The capacity of the circuit can be easily extended to handle up to nine persons by removing the connection of pin 1 from reset pin (15) and utilising Q1 to Q9 outputs of CD4017 counters. Additional inverters, AND gateS and diodes will, however, be required.

Hope you will help me in this project.[/color][/size][/font]