Week -2
1) Simulink Model Of Door Bell Using Solenoid Block
Aim:
To create a situation where the switch is closed to observe the physical movement of plunger.
Theory:
Electromagnet is a type of magnet in which the magnetic field is produced by passing an electric current.
In this experiment we will observe that when the switch is closed, the electromagnet recieves electrical power from the battery and pulls the metal arm to hit the bell producing sound using Simulink.
Simulation Model:
i)As shown in the above model, a battery is connected to switch and the solenoid block .
ii)The secondary side of the solenoid block is connected to an Ideal translational motor sensor.
iii)In order to make the switch close for two seconds the pulse is generated. Solver configuration and electrical reference are connected.
Input:
Output:
Result:
Thus the situation is created where the switch is closed to observe the plunger movement.
2) Thermistor to sense the temperature and Turn ON or OFF the Fan
Aim:
To use a thermistor to sense the temperature of the heater and turn on or off the fan.
Theory:
A thermistor is a resistance thermometer whose resistance is dependent on temperature. There are two types of thermistors:
i)Negative Temperature Coefficient- Temperature value increases with decrease in resistance.
ii)Positive Temperature Coefficient- Resistance value will increase as the temperature rises.
Simulation Model:
Input Signal:
Input signal is given through Signal generator as per the conditions given.
The input is given in degree C and changes are made accordingly in the reference input of the thermistor.
Output:
Thermal source:
i)An ideal energy source in a thermal network that can maintain a controlled heat flow rate regardless of the temperature difference.
ii)The heat flow rate is set by the physical signal port S.
iii)A positive heat flow rate flows from port A to port B.
Electrical and Mechanical Circuit:
Output Switch:
The output from the thermistor is viewed both by using DC motor and the Switche {On (1) and Off(0)}.When the temperature is above 25 degree Celsius the switch attains positive value above 0 and zero when the temperature is less than 25 degree Celsius.
Result:
Thus the thermistor is used to sense the temperature of the heater and to turn on or off the fan.