Week -2

AIM:To make a simulink model of a doorbell using solenoid block.

To use a thermistor to sense the temperature of a heater & run on or turn off the fan

1.Doorbell

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

*The switch block used is controlled by external physical signal.if the external signal is greater than the thresold parameter then the switch is closed, otherwise switch is open.

*The solinoid block is connected with switch and battery and we wii get a complete electrical circuit. the port c is connected with mechanical reference

*The ideal transalational sensor is connected with solenoid block R to observe the movment of the plunger

*scope is connected with the ideal translational sensor to get the output

*ps-simulink converter is used to convert the physical signal to simulink signal

*solver configuration:each physical network represented by a connected simscape blocks requires solver setting information for simulation

2.Thermistor

Model explanation :

*signal build block is used to input the values

*Controled temperature source represents an ideal source of thermal energy that can maintain a controled temperature difference regardless of the heat flow rate.the temperature differance is set by the physical signal port S. a positive temperature differance causes the temperature at port B to be greater than the temperature at point A

*Thermistor is a type resistor whose resistanc eis based upon temperature

*A linear resistor is used inorder to control the amount of current from the battery

*The voltage sensor is used to vonvert the voltage measured between two pints into physical signal

*voltage source which represents dc or ac

*electrical referance block is given

*solver configuration:each physical network represented by a connected simscape blocks requires solver setting information for simulation

RESULTS:

DOOR BELL:

Time period given is 2 seconds to the pulse generator to open and close the switch.when the switch is closed the solenoid blocks receives electrical power from the battery and the plunger move from port R to C to hit the bell and produce sound

THERMISTOR:

For 0 to 10 s fan is off condition becouse temperature is 293k which is below the thresold 298k.after 10 s temperature gose to 300k then the switch will be in ON condition as the temperature exceeds 298k.after 30s fan will turn off as the temperature comes down to 296k which is below the threshold temperature of 298k.