Week -2

Aim:-

1. To make a simulink model of a doorbell using solenoid block.
2. To use a thermistor to sense the temperature of a heater & turn on or turn off the fan.

1.Doorbell

Block Used:-

• Pulse generator
• Switch
• Battery
• Electrical reference
• Solenoid
• Mechanical Translational Refernce
• Ideal Translational Motion Sensor
• Mechanical Translational Reference
• Solver Configuraation

SIMULINK MODEL OF DOORBELL:-

Simulink Model Explanation:-

• The pulse generator is used to create square wave pulses at regular intervals.The block waveform parameters Amplitude, pulse width,period and phase delay, determine the shape of the output waveform.
• T
• The switch block used is controllled by external physical signal.
• The Solenoid block is connected with switch and battery and we will get a complete electrical circuit.The port C is connected with mechanical reference.
• The ideal translational sensor is connected with solenoid block R to observe the movement of the plunger.
• scope is connected with ideal translational sensor to get the output.
• P-S -simulinnk convertor is used to convert physical signal to simulink signal.
• Solver configuration- Each physical network represented by connecting simscape blocks requires solver setting information for simulation.

Input pulse Rate:-

Cycle time 4sec per pulse given as 2 seecond as a condition. The Graph will show the cycle as below:-

Output:-

2.Thermistor

Inputs:- Temperature source :- `20@C` from 0 to 10 sec, `27@C` from 10 to 30 sec, `23@C`from 30 to 50 sec.

Fan Conditions:- ON if the temperature above `25@C`, OFF otherwise.

SIMULINK MODEL:-

Simulink model explanation:-

• At point 1,Time = 0 sec, Temperature = 293 k
• At point 2, Time = 10 sec, Temperature = 300 k
• At point 3, Time = 30 sec , Temperatue = 300 k
• At point 4, Time = 30 sec, Temperature = 296 k
• At point 5, Time = 50 sec, Temperature = 296 k

1. Controlled Temperature source :- is an ideal energ source in a thermal network that can maintain a controlled temp. diffenrece regardless of the heat flow rate.The temp. difference is set by physical signal port S. A positive temp. defference causes the temp. at port B to be greater than the temp. at port A.
2. Thermistor is a type of resistor whose resistance is based upon temp.
3. The voltage sensor is used to convert the voltage measured between two points into a physical signal.
4. Voltage source repredents AC or DC.
5. Electric reference port must be there at ground.
6. Solver Configuration:- Each physical network represented by a connected simscape blocks requires solver setting information for simulation.

RESULT:-

2. Thermistor:-

For 0 to 10 fan is OFF condition because temperature is 293k which is below the threshhold .After 10s temperature goes to 300k then the switch will be ON condition.After 30 sec fan will turn OFF as the temperature comes down to 296 k which is below the threshhold temperature.