Output Devices





    Task of the week

    What I have did

    Individual assignment :

  • Studied about BLDC and wiper motor I am using in my final project.

  • Add an output device to a microcontroller board you have designed

  • Have simulate the working of DC motor with ldr readings in 'Thinker cad’ software.

  • Program it to do something.

  • Connected the simple DC toy motor and ldr to and heve programmed it to analyzed the working of output with input.

    Group assignment :

  • Have programmed it and also have shows the video of opertion.

    Measure the power consumption of an output device.

  • Have studied the relay and its specifications.

  • Have run it on the final project board.

  • Have recorded the video of operation.

  • In the Group assignment have measure the power consumption of an an output device.

    Week-11 :

    This week I have studied some things related to my “Final project”, especially about electronics part in the project. I have first various components and there connections with each other with the help of various boards. I have first deiced the main motor which I am going to be use in my project, it will be the BLDC motor.

    Motor having following specification : -

  • Power: - 1500 watt

  • Voltage: - 48volt

  • Speed: - 2000-6000 RPM

  • Current: - 90 AMPS

    To run the hopper blades I am using Wiper motor with following specifications : -

  • Power: - 120 watt

  • Input voltage: - 12volt

  • Input current: - 10 amp

    Especially, this week was about out-put board. After analyzing the requirement of project, that, the shredder should start when there is intense sunlight let us fix the value of 500lux. If my input sensor that is “LDR” senses this value, it will send the signal to both my motors that is main motor and hopper motor. In the input week I have design and have tested my “LDR” sensor board. In this week I need to be focused on output side. After discussing with my instructor Komal Raut, Suhas sir and senior DIC fellow in Vigyan Ashram Yogeshree the analysis of simplicity of the system is done. This discussion was also helped me to decide that I need to use “MOSFET” (Metal oxide semiconductor field effect transistor) in my project before the motor. Because I am going to use “Attiny44” as my driver IC and after reading its data sheet I came to know that it gives 5 volts as input voltage. But the motor will require about 12 volts to run so, by using MOSFET will help to magnify the charge.

    Individual Assgnment : -

    In this week I have decide to run the DC motor by reading the signal of ‘ldr’. The reason behind this is I want to test the maximum value of sun radiation read by “ldr” and second is whether the motor will run by reading the value of ldr. For that first I have design a simple circuit in Tinker cad virtual simulation software where I have used following components: -

  • Arduino UNO :- as a microcontroller.

  • DC motor: - as a output device.

  • LDR: - on output side.

  • A resistor: - we cannot connect ldr directly to the supply as it will get damage. So we require to use resistor between ldr and signal pin.

    After calling all these components in working window I have connected them with each other then I have written the code where I have set the limit of ldr as 500 lux and have started the simulation. Also, I have changed the value of ldr gradually and have view it on Serial monitor.

    I have observed a interesting thing that when I have set the ldr value below 500 lux the motor speed was “0” that is it doesn’t get start. On the other hand when I have set the value above 500 lux and continue to increase it the speed also goes on increasing.

Week1-2

    After testing this circuit in ‘Thinker cad’ I have done these connections on breadboard before designing an actual circuit. The surprising thing was the motor doesn’t get started. I have rechecked all the connections it was as per the connections in the thinker cad. I have connected the motor directly the VCC of 5 volt and another to the ground. The motor was ok; there were no problem with motor.

    So, I have asked for to my friend Vipul and Snehal they are Electronics Engineers. They have suggested me to use transistor between ldr and resistor and I have reload the cod on the board and my motor started. It shows the exact performance that it reads the value of ldr and the speed of motor changes with change in the value of light intensity.

Week1-2

    Coponentes on the circuit: -

  • LDR

  • Arduino UNO

  • BC547 Transistor

  • DC Motor

  • 1 kohm resistor

  • 10 k ohm potentiometer

  • Connecting wires

Week1-2

    After uploading the code I have also check the input and output values on the serial monitor. Here it shows as the value of ldr value changes with change in the speed of motor.

Week1-2

    This was the biggest movement for me because I have tried a lot to run this circuit as the application is same for my final project. I got the idea that what components I need to be use in my circuit, know I will design my final output board. I have also uploaded the operating on YouTube.

    Components on the circuit: -

    I have used the code shown below to control the motor on the input readings of LDR.


	
                
 
 modified by Tejswini Chaudhari
 10 july 2020
 
 
int //x; // input of LDR
int //y; // o/p Pwm value to be given to the base of the transistor to get reduced o/p voltage

void setup() {


pinMode(A0, INPUT);
pinMode(6, OUTPUT);


Serial.begin(9600);

}	


void loop() {
x = analogRead(A0);/ analog input from the pin A0 connected to LDR and POT. end
y = map(x,0,1023,0,255);/ Mapping or converting the value bw minimum to maximum analog value to the pwm value
analogWrite(6,y);/ Writing this analog value to pin 6 which is connected to the base of the transistor to get reduced o/p voltage


Serial.print ("LDR input");
Serial.print(x);


Serial.print ("\t");


  Serial.print (" O/P PWM value ");
Serial.print(y);
Serial.println(); 


   delay(1000);
 
 
   }

    Relay: -

    I have chose the relay which have screw terminals. The pins which are connected to the board are the low terminals and the screw terminals are the high voltage side of the relay and this is connected to drive the high voltage devices like motor.

    On the low voltage side of the relay we can see the three terminals GND, Vcc, and S for signal. On the high voltage side there are three screw therminals NC,C, and NO.

    Short discription of relay pins

  • GND is the ground pin.

  • Vcc will get the +5 volt from the board header pin.

  • S is the signal pin connected to the digital I/O pin of the board.

  • C common carries voltage from NO and NC.

  • NO is normally open terminal.

  • NC is normally closed terminal.

    Normally open and normally closed are the two two main pins of the relay. With normally open, the switch is off until the we get the signal from the signal pin on the board. With normally closed the switch is off until we get the signal from the board.

    In my final project I am using the relay to switch the wiper motor of hopper ON/OFF.

Week1-2
Week1-2

    I have used this code to turn the relay ON/OFF: -

    I have programmed the board to operate relay using Fab ISP


	

                
//Created by : Tejswini Chaudhari
//Relay ON/OFF

// the setup function runs once when you press reset or power the board
void setup() {
      //x; initialize digital pin LED_BUILTIN as an output.

            pinMode(13, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
                        digitalWrite(13, HIGH);   // turn the LED on (HIGH is the voltage level)  
			delay(1000,);             // wait for a second.
			digitalWrite(13, LOW);    // turn the LED off by making the voltage LOW.
			delay(1000,);             // wait for a second.

}

    Set-up of connecting the relay to my main project board of Atmega328p: -

    Description of final project board is given in the Final project page.

Week1-2

    Video shows the On/OFF operation of relay: -

    Download design files : -

    Learning outcomes : -

  • In this week I have studied different output devices like motor and its specifications.

  • How to run the motor on the input signals of ldr.

  • Have also studied about relay and its specifications.

  • How to use realy as a switch to operate high voltage devices like motor.

  • Programmed the realy to ON/OFF.

Creative Commons License
Solar Automatic Shredder by Tejswini Chaudhari is licensed under a Creative Commons Attribution-ShareAlike 4.0
International License