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Showing posts from June, 2011

Network Analysis for Electric Circuits

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Network Analysis for electric circuits are the different useful techniques related to several currents , emfs , and resistance voltages in such circuit. This is somewhat the collection of techniques of finding the voltages and currents in every component of the network. Some of those techniques are already mentioned in this online tutorial of Electrical Engineering. Kirchhoff''s Voltage Law or KVL Kirchhoff''s Current Law or KCL There are six remaining useful techniques that we are going to learn. The practical example of each analysis will be given in my next post. This is for you to comprehend first what each theory is all about. So, let's begin the first useful technique in analyzing network.  Thevenin's Theorem Consider the figure below which schematically represents the two-terminal network of constant emf's and resistances; a high-resistance voltmeter, connected to the accessible terminals, will indicate the so called open circuit voltage v oc . If a

What Is Electric Power?

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If we are going to recall our Physics subject, it is said that whenever a force is applied that causes motion the work is said to be done. Take a look on the illustration below:  Forces that work is done and  forces not doing work. The first figure shown above are combination of forces which work is done and forces which work is not done. (a)The picture in which the shelf is held under tension does not cause motion, thus work is not done. (b) The second picture in which the woman pushes the cart causes motion, thus the work is done. (c) The man applied tension in the string is not working since as there is no movement in the direction of the force. (d) The track applied horizontal force on the log is doing work. The potential difference between any two points in an  electric circuit , which gives rise to a voltage  and when connected causes electron to move and current to flow. This is one of a good example in which forces causing motion, thus causing work to be done. Talking about w

Interfacing a DS18S20 with an AVR

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This can be a complete project on its own - a simple DIY digital thermometer with LCD display and only a handful of parts - ATMEGA88, DS18S20 and only a resistor running off a regulated 5v supply. Display type - LCD (can be 16x1, 16x2 or anything larger) Controller: ATMEGA88 Programming Language: BASIC Compiler: mikroBASIC PRO for AVR ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''

Temperature sensor with PIC18 and MCP9700

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 This can be a complete project on its own - a simple DIY digital thermometer with LCD display and only a handful of parts - the PIC18F45K20, LM35 and a small number of resistors and capacitors running off a regulated 5v supply. Display type - LCD (can be 16x1, 16x2 or anything larger) Controller: PIC18F45K20 Programming Language: BASIC Compiler: mikroBASIC PRO for PIC v3.20 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''

Example of how to generate PWM in mikroC using the CCP module

//Program to generate 40kHz output at RC2(CCP1) pin //Microcontroller: Microchip PIC18452 //Language: C //Compiler: mikroC v8.20 //Programmer: Tahmid void main (void){      TRISC = 0;      PORTC = 0;      ADCON1 = 7;      T2CON = 0;      TMR2 = 0;      PWM1_Init(40000); //40kHz      PWM1_Change_Duty(128); //50% duty cycle // Choose Duty cycle as such: // PWM_Change_Duty(x); // x = ( (Duty Cycle in %) / 100) * 255      PWM1_Start(); //Start PWM      while (1){ //Loop forever // Whatever else might be needed to be done while PWM is running      } } In mikroC, you set the duty cycle by using the function PWM1_Change_duty(x). The value you put within the parentheses (x) has to be between 0 and 255. 0 means 0 duty cycle, 255 means 100% duty cycle, so 128 means 50%. You get PWM output at RC2 (pin 17).

Ohm's Law Series-Parallel Circuits Calculation

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To end up the discussion of Series-Parallel Circuits , I would like to post this last one remaining topic which is about Ohm's Law of Series-Parallel Circuits for currents and voltages . I did not even mentioned in my previous topics on how to deal with its currents and voltages regarding this type of circuit connection.  Ohms Law in Series-Parallel Circuits Ohm's Law in Series-Parallel Circuits - Current The total current of the series-parallel circuits depends on the total resistance offered by the circuit when connected across the voltage source. The current flow in the entire circuit and it will divide to flow through parallel branches. In case of parallel branch, the current is inversely proportional to the resistance of the branch - that is the greater current flows through the least resistance and vice-versa. Then, the current will then sum up again after flowing in different circuit branch which is the same as the current source or total current. The total circuit curr

The Bridge Resistor Circuit

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This is already the Part-3 lessons for Series-Parallel Circuits . Today we will be dealing with another type of complex circuit which you do not know yet - particularly for the beginners. Suppose you have a type of simple circuit below. You will notice that there is an extra resistor of R3 connecting to the two parallel branches of the parallel circuit connection and in such way it was interrupted to the leads of the new resistor. This new resistor (R3) is called a bridge . R3 is called the Bridge Resistor  Take a look at the circuit above. If you look at the upper part of R3 resistor, wherein R1, R2 and R3 are all connected together. You will notice a new arrangement of connection. This arrangement from its similarity to the shape of the Greek letter D (delta), is said to be delta connected . Here is the diagram below to see clearly what I'm talking about. This is the illustrative diagram for delta connection   The equivalent connection of left diagram is called the Y

Series-Parallel Circuits- Part 2

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This is just the continuation of my post yesterday about Series-Parallel Circuits- Part 1 . I've already provided you the steps on how to simplify a simple series-parallel connections. Today, I will give you an example on how to solve that circuit using that steps mentioned before. The practical example that I will show you below is how to break down a complex circuits to find the total resistance. Refer to figure below: Circuit Problem for Series-Parallel Let's say:  R1= 7 ohms, R2= 10 ohms, R3= 6 ohms and R4= 4 ohms. We are required to get the total resistance of the circuit. Using the steps that previously discussed here . We can redraw an equivalent circuit in a way that we can understand it well. The figure below is the redrawn circuit for the given problem above. 1. Redraw the circuit.  Redrawn Series-Parallel From the redrawn circuit above. we can now simplify R3 and R4. Lets name it R3-4 = 6+4 = 10 ohms. 2. The next step is by getting the resistance between R2 and R3-4

Series-Parallel Circuits- Part 1

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It's been a long time ago when I posted my last topic about Electric Circuits .  Though its very difficult to have time to write a topic for this blog, this site will always be alive for you. I would like to thank first those who have subscribed to this blog. Well, let's talk about another basic topic about Basic Electrical Engineering . This is about Series-Parallel Circuits. For those who are just new with this site, you can surely catch up with my previous post at Electrical Engineering Syllabus that I've provided last time. Circuits can be connected into complex circuits consisting of three or more resistors. One part of the circuit is in series and the other part could be connected in parallel. This connection is called the Series-Parallel Circuits . There are two types of series-parallel connections: the first one is the resistance in series with a parallel combination and the other one is the series in which the parallel combination have a series of resistances. Let

Sen. Ultrasonico Arduino + Processing

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El sensor Ultrasonico ocupado en este proyecto es el SRF-02 - Datasheet .                           Combinando un poco Arduino con Processing puede hacer que tu proyecto se vea mejor, un ejemplo de esto es lo que he hecho con un sensor Ultrasonico donde como en cualquier proyecto se pueden imprimir los datos en una LCD. La lcd esta conectada a partir del pin 7 hacia el 0 y conectada con cables a los pines 13, 12 ... etc.esta es una forma portátil del medidor de distancias Ultrasonico o bien con processing: Se nota bastante la diferencia apesar de que es el mismo proyecto, medir distancias con un sensor ultrasonico, ademas que es mas económico ya que no requerimos de una LCD si no que en nuestra misma pantalla podemos visualizar los datos. Descargar Proyecto. Dependencias: Necesita la ultima version de NewSoftSerial.