Week -2

Aim:

* To make a simulink model of doorbell using solenoid block

* To sense the temperature of heater and turn it off using thermistor and other corresponding elements.

i) Model For Doorbell:

Components and Usage:

i) Pulse Generator: Used to give Input pulse signals.

ii) Battery: Acts as power source to the system.

iii) Switch: They act as control unit for entire system. In this model, Switch of two inputs is used, which one is connected to the battery and another one is connected to pulse generator.

iv) Simulink-PS: Converts Simulink signal to Physical Signal.

v) PS-Simulink: Converts Physical signal to Simulink Signal.

vi) Electrical Reference: Representing the grounding system for Making an electrical reference point in a fixed frame

vii) Mechanical Reference: Representing the grounding system for Making a mechanical reference point in a fixed frame

viii) Ideal Translational Motion Sensor: Measures velocity and displacement V and P, denoting Displacement and Velocity respectively.

ix) Solver Configuration: Solves the simulation through solver settings

x) Scope: Displays output in graphical term..

xi) Solenoid: A coil of wire usually in cylindrical form that when carrying a current acts like a magnet so that a movable core is drawn into the coil when a current flows and that is used especially as a switch or control for a mechanical device.

Figure-1 (block diagram)

Figure-2 (we could see the decrease in displacement gradually when the plunger is getting closer to the bell and increase when moves away)

Figure-3 ( switch can be closed for 2 seconds by adjusting phase delay)

Figure-4

ii) Model for Thermistor:

Components and Usage:

i) Repeating sequence stair: Consists of discrete values which we provide.

ii) Thermal Reference: Representing the grounding system for Making a thermal reference point in a fixed frame.

iii) Controlled temperature source: Used to maintain a controlled temperature difference. Port S is the temperature difference, A&B is used to connect system.

iv) Thermistor: Used to measure the temperature in a circuit with respect to resistor as resistance, which is dependant on temperature. Port A is connected to port B of temperature sensor.

v) Voltage Source: Measures the voltage signal by converting it into physical signal.

vi) Battery: Acts as power source to the system.

vii) Switch:They act as control unit for entire system. Two constant block is connected which represents as switch, second input switch is connected to voltage sensor.

viii) Simulink-PS: Converts Simulink signal to Physical Signal.

ix) PS-Simulink: Converts Physical signal to Simylink signal.

x) Solver configuration: Solves the simulation through solver settings

xi) Scope: Displays output in graphical term..

Condition for the switch is ON when the temperature is greater than 25.

Here the condition of the fan to turn ON or OFF with respect to change in temperature is provided as threshold change, when threshold is greater than switch, it remains OFF

Figure-1 (block diagram)

Figure-2 ( the values of the temperature 20,27,23 are represented in KELVIN, A sample time of 10 seconds is assigned)

Figure-3 (threshold values after simulation)

Figure-4 ( we can see when the time between 10-30, the position of the switch is turned on and maximum threshold is obtained..

Result:

Thus, the simulink model of doorbell and heater using thermistor has been made and the output is obtained by using SIMULINK.