In this Instructable I will be going over the basics components of Electrical Engineering as well as there biggest uses in the industry.
I will also give brief instructions on where to find and salvage them.
Step 1: Switches
Switches are one of the most basic electrical components but are also one of the most used in electrical engineering.
A switch responds to an external force to mechanically change an electric signal. Switches are used to turn electric circuits ON and OFF and to switch electric circuits. Basically what this means is that when you push down or flick a switch you are allowing current to flow through to the rest of the circuit.
We have many different kinds of switches the most common are
- Toggle Switch: Toggle switches work by connecting and disengaging two pieces of metal within the switch. The common light switch used in household wiring is an example of a toggle switch.
- Push button Switch: A push button switch is a two-position device that when pressed will go to a 0 state but when release will revert back to its natural 1 state, you will most commonly find these in keyboards (buttons)
- Selector Switch: Selector switches are actuated with a rotary knob or lever of some sort to select one of two or more positions. Like the toggle switch, selector switches can either rest in any of their positions or contain spring-return mechanisms for momentary operation
Step 2: Diodes
A Diode is the simplest two-terminal unilateral semiconductor device. It allows current to flow only in one direction and blocks the current that flows in the opposite direction. The two terminals of the diode are called as anode and cathode. The characteristics of a diode closely match to that of a switch. An ideal switch when open does not conduct current in either directions and in closed state conducts in both directions
There are many different types of diodes the most common are:
Zener Diode: The Zener Diode allows current in reverse direction when the applied voltage reaches the breakdown voltage. (Based of principle of zener breakdown.)
Light Emitting Diode: The LED converts current into light. This type of diode is especially popular and is most commonly found in small electronics stop street lights and we may even see it finding its way into house lighting being cheaper and more Eco friendly.
Constant current diode: It is also known as current-regulating diode or constant current diode or current-limiting diode or diode-connected transistor "mouth full". The function of the diode is regulating the voltage at a particular current. It functions as a two terminal current limiter. In this JFET acts as current limiter to achieve high output impedance.
Step 3: The resistor
The resistor is a passive two pole component used to limit the amount of current that is allowed to flow at any given time as well as the voltage. different resistors can resist more than others the way you work out a resistors resistance is by looking at the 4 stripes on the main body of the resistor the different colors show the resistance, to work out the color code you can use a resistor calculator like this one:
Step 4: Batteries
An electric battery is a device consisting of two or more electro-chemical cells that convert stored chemical energy into electrical energy. Each cell has a positive terminal, or cathode, and a negative terminal, or anode. The terminal marked positive is at a higher electrical potential energy than is the terminal marked negative. These are especially handy when it comes to designing portable devices. Now there are many different kinds of batteries such as lead acid or AGM batteries but i wont get into it to much as it doesn't really change the concept of the battery. All you need to know is that a battery(cell) can store a charge a release it at a later point without deteriorating too much.
You can find these in pretty much any portable device. (laptop, remote, phone, rc toys)
Step 5: Capacitor
A capacitor is a two-terminal, electrical
component used to temporarily store a charge in an electric feild. This is use full in Electrical Engineering because it can be used to smooth out varying DC supplies aswell as filtering circuits (high pass, low pass or band pass) they are even used as temporary batteries.
The most common types of capacitors you will find are:
- Supercap: Also known as a ultracapacitor, as the name implies these capacitors have very large amounts of capacitance.
- Elecrtrolytic Capacitor: These are a type of capacitor that are polarised (they can only work in one direction) these are able to offer high capacitance values mostly above 1 μF. these are mostly used for low friquency applications
- Ceramic Capacitor: Is a type of capacitor are that can store a charge anywhere from a picofarad to around 0.1 microfarad. you will find these in pretty much all electronics as they are so cheap to make and have such a wide range of use.
Step 6: Transistors
Transistors are is a small mostly 3 pole component made of elements in the group 4 in the periodic table, Silicon being the most common. To understand it think of it like this, Your brain has billions upon billions of neurons. The neurons let you think and remember things, Computers act the same way except the computers neuron is called a Transistor. The transistor acts either like anamplifier (Taking a small electric current at an input current and then produces a much bigger output current, you can see this at work in hearing aids or microphones) or like a Switch (taking a small current flowing through one part of a transistor can make a much bigger current flow through another part of it. Basically the small current switches on the larger one, this is how a computers chips work.)
Step 7: Potentiometer
A Potentiometer is a knob that has variable resistance which can result in the dimming of your lights or even sending information back to your micro controller this component normally has 3 poles also called a 3 pole resistor it works in the same way as a voltage divider except for the fact that this has variable outputs. You will often find these in house holds or sound controllers. (speakers)
Step 8: Motors
Motors is a device that converts direct current into mechanical power. They rely on the forces produced by magnetic fields. It does this by having a coil of wire with a current running through it generates an electromagnetic field. The direction and magnitude of the magnetic field produced by the coil can be changed with the direction and magnitude of the current flowing through it.
The most common types of motors are
DC motors : This Motors simply starts spinning if you give it DC connection the speed and direction all depends on the arrangement of the positive and negative poles as well as the amount of current you put through it.
Servo Motors: These motors are awesome because they can turn to any specific location within 660 or 180 depending on the servo you have (to find out more about servos please check my other instructable about servos: http://www.instructables.com/id/An-Introduction-To-Servos/
Stepper Motors: The main difference between them and all the other motors, is the way they revolve. Unlike other motors, stepper motors does not continuously rotate Instead, they rotate in steps (from which they got the name). Each step is a fraction of a full circle. This fraction depends mostly from the mechanical parts of the motor, and from the driving method.