Week -2

Aim :- 1. Create a simulink model of Doorbell using solenoid block.

2. Use Thermistor to sense the temperature of a heater and also turn on or off the fan as per given conditions.

Objective :- 1. To create a doorbell model,where the switch is closed for 2 seconds and then release,and observe the output.

2. Use thermistor to sense the temperature of the heater,

Temp source 20 degree celcius 0 to 10 sec,

Temp source 27 degree celcius 10 to 30 sec,

Temp source 23 degree celcius 30 to 50 sec,

Fan condition ON if temp exceeds 25 degree celcius otherwise off.

Theory Doorbell :-

Solenoid,

Solenoids are basically coils of wire. These generate a magnetic field which strikes a force over a metallic element. This happens

whenwe apply the electric current to the solenoid.Solenoids help the energy to convert into action instantly. Therefore, these work

decently for those applications which require immediate action.

Simulink Model :-

Output :-

Explanation :-

Blocks used in the current model :-

1. Switch :- This block is used to control flow rate of the current i.e, ON or OFF.

2. Battery :- This block represents a voltage source which is further used in solenoid,It has two ports(+,-).

3. solenoid :- This block represents a electrical and mechanical properties of the solenoid.

4. PS Converter :- This block is used to convert physical signals into the unitless simulink input signal and vice versa.

5. Electrical Reference :-This block basically represents earthing to the circuit.

6. Pulse Generator :- It is capable of generating pulses with widths,and also regulate the output of the battery.

7. scope :- This block displays the signal generated during the simulation.

Stepwise Explanation,

First i dragged down all the blocks into the blank model.

Then one terminal of the battery is connected to the solenoid block and another to the switch.

Then one remain terminal of the battery is connected to the -ve terminal of the solenoid electrical part.

Then two mechanical terminal of the solenoid is connected to the ideal translational motion sensor.

Then one ps converter is connectedto the switch and another one is connected to the translational motion sensor.

Then further scope is connected to the ps converter.

2. Thermistor :-

A thermistor is a type of resistor whose resistance is strongly dependent on temperature, more so than in standard resistors. The

word is a combination of thermal and resistor.Thermistors act as a passive component in a circuit. NTC stands for Negative

Temperature Coefficient.

Simulink Model :-

Explanation :-

First i dragged down the important required blocks which is Thermistor,Voltage sensor,Battery,Ideal temp source.

Then first complete our electrical circuit which is battery,thermistor and voltage sensor.

Now electrical reference is connected to the electrical circuit.

For thermistor we need one temp source which is then connected to the thermistor.

Then signal builder is connected to the temp source through the signal converter.

Neg port of the voltage sensor is connected to the switch through the signal converter.

Switch has three ports,two of them are data ports which are oen and three,and second port is control port.

For output of the simulation we connect two scope to the two data port of the switch.

Output :-

Conclusion :-

Here I able to learn, using simulation how to create a model with specific input values.