Electric and electronic components

Self restarting circuits breaker

A bimetal strip act as a movable contact, under normal current, the bimetal strip remain cool and straight and the connection remains closed, when a problem exists in the circuits high current through the strip causes oevrheating, the circuit breaker heats up, the high expansion met the bimetal strip expand more than the low expansion metal, making the strip warp or bend, this open contact in the circuit breaker.

Photodiode

All pn junction are sensitive to light, it is a pn junction device that can function in one of two ways, depending on how it is connected in a circuits, it can produce a low voltage when excited by light, it can a;so be used to control current by allow current flow when excited by light.

Photonic device

Any device that can emit or detect light, a photonic is a particle of electromagnetic light energy, photonics is a fast growing field of electronic and photonic semiconductors are now being found in automotive electronics.

Coil

Choke or inductor, consists of insulated wire loops placed close together to create an electromagnetic field, it usually wrapped around an iron core to strenght the electromagnetic properties, electrical circuits to resists the fluctuation of current and voltage, unlike capacitiors, coils provide little opposition to direct current, in automotive applications, cool are commonly used in electric devices to provides a magnetic field, they're used in transformers, solenoids, motors, relays, sensors and other components.

Normally closed switch

Complete it's internal connection when at rest (not activated), activating the switch opens the internal contacts to stop current flow.

Electromagnetic field in the armature

Current flow from the negative terminal of the power source, through brush A and commutators A brush B and back to the positive terminal of the powder source, this sets up electromagnetic field in the armature.

Liquid crystal display

Device that has a fluid crystal material sandwiches between two sealed glass plates, this device that has a fluid crystal material sandwiches between two sealed glass plates, this device can polarize light (make all the light wave vibrates in a single plane) to display numbers, letters or other images, both glass plates have a polarizing film on them, but one is turned at 90 degree to the othet.

Piezoelectric crystal

Device that produce a low current output when physical pressure is applied, a diaphragm can be linked to the piezoelectric crystal to make a microphone, sound wave make the diaphragm flex back and forth, wihich places various amount of pressure on the piezoelectric crystal, as a result, the crystal produces small voltages fluctuations, the strength of the voltage signal can be used as an indication of pressure from sound waves, like a microphone.

Relay

Devices that use a small input current to control a larger current in a circuits, a small coil open and closed a set of contact points, without relays, huge switch would be needed to carry the high current load of some electric circuits. ex, vehicle horn; when press horn; small control current flow to relay, close the contact relay and large current flow to energize the horn.

Rectification

Diodes are commonly used to convert alternative current to direct current, this process is called rectification, of a diode is placed in a circuit and with alternating current, the diode allows current in one direction only.

No types semiconductor

Doped so that it has excess electrons, substances are added to the silicon to provided free electron that can move through the night types semiconductor material, N= negative. It's pure state, silicon is good insulator, it's semiconductor properties, n and put types are determines by the number of holes or free electrons that result from the doping process, neither type is very useful by itself, by using the two types together, however, numerous useful devices can be manufacture.

Solenoid

Electromagnet that have moves a metal core, or plunger, the core movement can be used to close very large electrical contacts or move parts into engagement., it used electric current to produce motion, this motion might be used to operate a trunk latch, when there is current through the solenoid winding, the magnetic field pulls the core into the winding, then when current is broken, spring action pushes the core back out.

Fiber optics

Field of eletronics in which light is used to carry data through small strands of plastic or glass fiber, each fiber is about the size of a human hair, hundred of fibers can be bundled into a single cable to transfer huge amounts of data.

Fuse panel

Fuse box, is a plastic housing with metal terminals that holds the vehicles fuse and other related electric components, such as relays, most fuse panels mount under the dash of the vehicles, in the engine compartment near the firewall, under the rear seat or in the trunk of mid or rear engine vehicles.

Fuse link

Fusible link, is a section of smaller gauge wire connected in series with the larger gauge circuit wiring, it is designed to serve as a very large fuse, normally located in the engine compartment, where power feeds from the 12 volt battery or starter solenoid, it usually wired between the 12 volt battery and the fuse panel, it provides circuits protection before the fuse box in the passenger compartment, of a wire is shorted to ground before it reach the fuse panel, the fuse link overheated and Burns in half, this protect the rest of the wiring from major damage.

Single pole, double throw switch

Has one movable contact arm but two different stationary contacts, the arm can make an electrical connection with either of the stationary contacts.

Double pole, double throw switch

Has two moving arms, each having two stationary contacts.

Resistors

If a circuit had no resistance, it would burn up from excess current and heat, and lightbulb, used a small resistance element inside a sealed glass housing to generate heat and light, it's limit and controlled currents flow in a circuits, resistor devices come in various shapes and sizee, depending on their function.

Alternating current

It can pass through a capacitor, the alternating current charges a capacitor while current is in one direction, then the capacitor discharges back into the circuit when the current changes direction. capacitors can be used as a noise suppressor to prevent static in the ratio or sound system, they are connected into the wiring to absorb or counteract voltage spikes that cause radio noise, in late model vehicles, microscopic capacitors are found in computer circuits, sound system, navigation system and printed circuits.

Voltage and current in a transformer

It inversely propotional, when a transformer increase voltage, current decrease, if a transformer reduces voltages, current increase. current can be sacrificed to gain voltage or voltage can be sacrificed to gain current.

Semiconductor

It made from silicon, germanium or other substance that conduct a limited amount of electricity in a manner that can be controlled, ex, silicon is a nonmetallic element contained in man toe of sand, to make a semiconductor, silicon is melted and cooked at about 2600 f (1428 c) then the silicon is doped or combined chemicall, with substance such as phosphorus and boron, this cause the silicon to grow into useful crystals (substances with symmetrical atomic structures)

Fuse

It use to protect a circuit from damage caused by excess current, it is connected in series with the circuit, right after the source, so that all current goes through the fuse. when current is normal, there is current through the fuse elemet, if something goes wrong in the circuit to increase current too much, the elemet of heats and melts, this breaks the circuits and protect the wires from overheating damage.

Mercy switch

It used liquid Mercy to open and close it's switch contacts, it's good conductor, it serve as a position switch that react to the location parts, it can be use to activate the underhood light or the trunk light in a vehicle, when the switch is on one position, the mercy does not touch the contacts, so the switch is open, when the switch is filled the other way (hood or trunk open), the Mercury flows down over the contacts to close the switch.

Starter solenoids

It used to complete the battery to starting motor circuits, it serve as a huge relay to connect this high amperage circuits, some starter solenoids also moved the starter gear into engagement with the flywheel ring gear on the back of the engine.

Fuse panels

It usually have a guide showing fuse circuits and fuse rating, in some vehicle, the fuse guides is printed on the back of the fuel panel cover, in others, the name of the circuits is abbreviated next to the fuse panels, this show which circuits is protected by each fuse, the fuse rating may also be printed next to the fuse socket in case a fuse is removed.

Diode

Made by joining a piece of my type semiconductor with a piece of type of piece of my type semiconductor with a piece of paper type semiconductor, a wire lead is attached that blocks direct current in one direction and passes direct current in the other direction, a diode, therefore, acts as an electric check valve.

Electric motors and armature

Magnetic field to produce a powerful rotating action, a set of winding is wound around a central core, this core shaft are called armature, the shaft mounted in bearing to allow the armature to rotate, either stationary permanent magnets or stationary windings.

Normally open switch

Open or disconnected when at rest (not activated), a push button switch is an example of a normally open switch.

Circuit breaker

Performs the same function as a fuse or fuse link, it protect a circuits from damage from excess current, however, it is not ruined when it is activated or tripped circuits breakers can sense a high current condition and disconnet the circuits temporaly , they automatically reconnect the circuit after it cool down, if the higher current condition still exists, this trip again and the cycle repeats, this action is ideal for headlight circuits, which must not turn off permanently.

Reverse bias voltage

Rating of the maximum voltage a diode can block without being damaged, if this voltage is exceeded, the diode is ruined, automotive diodes are rated to operates on less than 15 volts.

Pressure switch

Reacts to change in internal pressure, most pressure switch have an internal diagraph attached to an electrical contact, when pressure drops below about 10 psi, the diaphragm is at rest and the contacts are open, when pressure becomes high enough, the diaphragm fixes to close the contact, complete the circuits, a common application for a pressure switch is the engine oil light circuits, when the diaphragm closes the contact, the oil pressure light on the dash is activated.

Phonetic systems

Reliable and efficient than all electronic system, they are also faster and take less space, laser and fiber development are progressing rapidly, enabling error free transmission of signals over distance greater than 100 miles without reamplification.

Turn ratio

Represent the relationship between the number of windinggs, or wraps of wire in each transformer coil, if both coils have the same number of winding, it is one to one (1;1), included voltage in the first coils, this equal input and output produces an isolation transfromer, which isolate one circuits from another.

Impedance

Resistance to alternating current at a given frequency. Transformer are made by wrapping an insulating wire around a core, usually an iron core, another set of winding is wrapped around a second core, of current through one set of wiring fluctuates (increase or decreases in lenght) voltage is included in the other set of winding stays the same, voltage is not included in the other winding.

Transistor

Semiconductor device that regulates current or voltage in a circuits, it can acts as a switch for electronic signals or serve as a current amplifier, trans-stand for transferable sistor stands for resistance, a transistor transfer or changes, from a resistor to a conductor with electric stimulation.

Signal transistor

Small transistor used to amplify low power signals or switch low currents on and off, these transistor are located in complex electronic circuits, such as those found in radio and computers, smaller signals transistor often feed current to the base circuits of power transistor.

Photovoltaic cell

Solar cell, is a photonic device that converts light directly into current, a basic photovoltaic cell, consists of a glass outer layer that contains a transparent negative terminal, an antireflective layer to increase the cells efficiency, and layer of n type semiconductor material, a layer of power type semiconductor material and metal base. it converts the photons to electrons, which form a current that can be used to power external device, the cell electromagnetic field also provides a voltages output of about 0.5 v.

Electronic components

Solid state components, are compose of semiconductor material, which allows the device to control electricity, they are typically smaller and lighter than most electric components and they do not consume as much energ, this is the fundamental advantage of electronic components.

Generally diode

Special type of diode that serve as a voltage regulator, it conducts current normally when it is forward biased, it also block current when it is reverse biased, however when a specific reverse bias voltage is reached, the zener diode begins to conduct current.

Push button switch

Spring loaded button that, when pressed, makes or breaks An electrical connection a cross two contacts, it's a push pull switch is a special type of push button switch that stays in each position until it's moved, in some vehicles, a pushed pull switch used to turn the headlights on and off, when the driver pulls the switch out, the headlight come on and remain on until the driver pushes the switch back to the office position.

Capacitor

Storage device for electrons or electrical energy, it's made by wrapping two conductor strips around an insulating strip or dielectric, the insulating strip allows the two conductor to be place close together but keeps them from touching.

Thermal switch

Temperature sensitive switch it opens and closes with changes in temperature, this type of switch used a bimetal strip (two different metals bonded together) so it warps and bends when heated. when the switch is cold, the bimetal strip is curved away from the internal switch contacts, so the circuits is open, when switch temperature increase the two metals in the bimetal strip expand at different rates, this cause the strip to straightten , closing the switch contacts, one application for a thermal switch is to sense engine overheating and operate a dash warning light or even shut down power to the ignition system to prevent engine damage.

fuse rating

The amount of current a fuse can handle before it's element melts, "20 ZA'' printed on the fuse means that the fuse is rated to protect a circuit designed for 20 amps, when you replace a fuse, always install a fuse with the same fuse rating, in automotive applications, the voltage value is understood to be 12 v.

Farads

The size or electrical storage ability of a capacitor is rated in farads, a 1 farads capacitor connected to a 1 volt source stores 6.28 x 10 power of (18) electrons, most capacitors cannot store this much electricity, however, only super capacitors used in hybrid drive trains or stereo systems can store more than this much energy, most small capacitors are generally rated in microfarads (uf) or picofarads (pf), a microfarads equals a millionth of a farad, a picofarads equals a trillionth of a farad, capacitor also have a voltage rating to prevent electrical arcing and component failure, any voltage applied must not exceed the capacitor voltage rating.

P type semiconductor

The two basic types of semiconductor are p types and n types, doped so that it has excess protons, this creates holes or spaces in the atoms for free electrons, as a result, of type semiconductor is a relatively positive substance that attracts electrons, please stand for positive.

Single pole, single throw switch

Toggle switch, has one swinging arm that can make contact with one stationary contact (pole), it is either open or closed and has two external terminals, this type of switch might be used for fog light or other dash mounted controls.

Transformer

Two sets of coils to transform voltage and current to higher or lower levels, for ex, an ignitions system coil is use to transform battery voltage into high voltage for firing the spark plugs, other types of transformers are use to isolate different parts of a circuits, reduce voltage or match the impedance of circuits sections.

Potentiometer

Variable resistor that has three electrical connections, it has one connection at each end of the resistance unit and one for the sliding contact, this allows for more complex used of the variable resistance, it can be used to produce a variable voltage drop or voltage signal, as the sliding contact moves along the resistance unit, the internal resistance and resulting voltage drop change, this type of variable resistor might be used as a sensor for a computer system.

Rheostat

Variable resistor with two electrical terminals (connections). one terminal is wired to one end of the resistance unit, the other terminal is connected to a sliding contact, turning the control knob moves the contact and alters the resistance value.

Direct current

When it applied to a circuits that contains a capacitor, electrons build up on the conductor strip attached to the negative terminal of the battery, as electrons build up, the capacitor becomes charged, a positive charge collects on the other conducted strip. when the charge in the capacitor equals the DC voltage from the battery, electrons can no longer flow through the capacitor, therfore , small capacitors can be used to even out voltage fluctuation, they supply extra voltage when the DC voltage dips and they absorb voltage if the DC voltage spikes.

Switch

connect or disconnect the power, supply in a circuit, for a list of common types of switches and their corresponding symbol,

Light emitting diode chip

is a housed in a plastic bulb, wire leads extend our the bottom of the housing, less can be used as an indicator lights in the dash panel and interior some lights, they are now used for exterior applications such as tailights, marker lights and headlights.

Smaller solenoids

it can be used to control engine throttle position and engine speed, solenoids are also used to open and close gasoline's injectors in an electronic fuel injection system.

Fiber optic cables

it carry light generated by less or laser diodes, which are similar to less but more powerful, the data stream to be carried is fed into the circuit as voltage, which modulates (changes) the light waves, the outer parts of each fiber is coated with a substance that makes the light bounce off the inner wall of the fiber and shoot out the other end.

Power transistor

it control high current levels, ex, power transistor are used to operate the speakers in radios, they are the output devices that regulates the fluctuating current that makes the speaker diaphragms vibrate and produce sound, power transistor are normally mounted on a heat sink, a heat sink is used to transfer heat away from a transistor, this helps keep the transistor from overheating, which would damage the semiconductor.

Fixed reistor

it has a set ohms values that does not change, a variable reistor has a range of internal reistance that can be adjusted, when you turn or slide a control knob, a contact moves along a resistor element, as the contact moves, a different amount, or length of resistance values, there are two basic types of variable resistor, rheostats and potentiometers.

Armatures North pole

its near the North pole of the stationary magnet, and it's South pole is near the South pole stationary magnet, since like charges repel, armature swings a quarter tuen, at this point, the North pole of the armature is near enough to be attracted to the South pole of the stationary magnet, so the armatures swings another quarter turn.

Transistor and relay

its perform the same function, they both can use a low control current to operate a much higher circuits current, however, a transistor is much smaller than a relay, and it does not have moving parts to wear out.

Light emitting diode

led is a photonic semiconductor that emit light when it's electrically energized, since an LED converts electricity directly into light, it is much more efficient than most other light sources, also a on junction with semiconductors made of gallium (chemical element) that have been doped with special substance, such as phosphorus, when the LED is connected to a power source, light is emitted, the chemical makeup of the doping material determines the color of the LED light.

Bipolar junction transistor

made by joining three semiconductor materials, and Npn transistor has two numbers type sermiconductor and one of type semiconductor bonded together, a PNP transistor has two p types semiconductor and one n type semiconductor, small wire leads are attached to each type material, the trigger lead, a low current through the base turns the transistor on, when the transistor is on, a high circuit current passes through the emitter and collector leads, a transistor can act as an electronic switch, much like an electric relay the action of a transistor compared to a relay to operate a horn circuit.

Step up transformer

one which is the second coil has more winding than the firs coil.the additional high voltages, for example in it's that has a turns ratio of 1'2 application of 12 volts to the first coils produces an output of 24 volts in the second automobile are ignition coils, which fire the spark plugs in the engines ignition system.

Photoresistor

semiconductor that acts as a resistor in the dark but change to a conductor when exposed to lght, if a battery is connected to the photoresistor with the light source off, no current is allowed through the device because the photoresistor has higher resistance, when the light source is turned on, resistance becomesmuch lower, and the photoresistor change to a conductor to allow current.

Commutators Revere rotation

since the commutators roster with the armatures, the current now flows from the negative terminal through brush A to commutators B, which reverse the flow through the armature , Because the flow is reverse, North pole are together again, soon the armature rotated a third quarter turms, altraction between the opposite poles cause the fourth quarter turn, completing one full rotation, the process then begins again.

Half and full wave rectification

single diode in series with and ac source produces half wave rectification, in this configuration, only half of each ac wave is allowed through, full wave rectification allows both halves of each ac wave though, both wave flows in the same direction, diode are commonly used inside a vehicles charging system alternator, the initial output of an alternator is ac, the AC must be rectified into DC for use in the automobile electric and electronic system.

No current

the circuits wiring and the bimetal strip cool to a temperature that is safe for circuit operation, the bimetal strip regains it's original shapeclosing the contacts and restarting current flow.

Commutators and brushes

the end of the armature coil are connected to two semicircular commutators, it attached to the armature, so they rotated with it, but they are also in contact with two stationary brushes that are connected to a power source.

Step down transformer

the second coil has fewer winding than the first coil, this reduce the output voltages compared to the input voltage, for ex, in it's that has a turns ratio of 2;1 12 volts in the first coil produce an output of only 6 volts in the second coil, it found in computers to lower voltage for integrated circuits.

liquid crystal aligned

the top plate, they reflect light, however then a charge is applied, their orientation changes and they block the light, the area of block light can be arranged by applying the charges to area of a specific shape, liquid crystal display have thousands of practical used, LCDs are used in the instrument cluster of late model vehicles to show speed, tachometer graphics, odometer displays and other information.

light detector

used to sense the light signals, the signal can then be amplified into a higher current signal, the signal can then be amplified into a higher current signal to operate other devices, one stranger of fiber optic materials can be used to send the same amount of electrical data as a large bundle of conventional metal wires.

Photovoltaic cells in series

we can increase bvoltage output, four silicon photovoltaic cells in series would generate approximately 2 v. if we connect the cell in parallel, the voltage stays the same, but the current output increase, this make it possible to use the output for higher load devices, such as a small fan to cool the inside of a vehicle when it is sitting in the hot sun.

Forward bias pn junction

when a diode is connected so that it acts as a conductor, it is said to have a forward bias, the battery charge pushes the electrons and holes closer to the pin junction (the common edge of the p type and n types semiconductor), this reduces the size of the depletion area (area surrounding the on junction that is good of hole and electrons) around the pin junction so that electrons can flow across the junction, a voltage drop of about 0.7 volts is need to produce a forward bias current across a diode.

Reverse bias

when a diode is wire so that it acts as an insultor, it has a reverse bias, the battery connections are reversed, so the electric charge pulls electron depletion area larger, blocking current through the diode.

Short circuit

without a fuse, and electrical fire could result from overheated wires glowing red hot, causing their insulation to ignite, result when a hot wire touch any ground, this may cause a tremendous amount of current through the circuit, the excess current can burn up wires ]in a fraction of a second, a fuse protects circuits from excess current and resulting damage.