Produced By Mike Hartlen Electrical Fundamentals THIS PRESENTATION ABOUT AUTOMOBILE SYSTEMS HAS BEEN DEVELOPED BY Mike Hartlen TEACHER OF AUTOMOTIVE TECHNOLOGY AT EASTERN SHORE DISTRICT HIGH SCHOOL

Produced By Mike Hartlen Unit Terms Matter Atom Molecule Element Ion Amperage Electron Proton Neutron Insulator Conductor Semi-Conductor Voltage Ohm Resistance Watt Direct Current (D/C) Alternating Current (A/C) Ampere

Produced By Mike Hartlen Matter Everything in the world is made of matter. Matter is anything that has mass and occupies space. Matter can be made up of a group or series of different atoms to form a molecule. Matter has three states: Solid, Liquid, and Vapour.

Produced By Mike Hartlen Molecule Example Imagine a lake. Now imagine taking the smallest particle or piece of water from the lake. You would have a single molecule of water, H2O, which is made up of two hydrogen atoms and one oxygen atom.

Produced By Mike Hartlen Water Molecule

Produced By Mike Hartlen Elements Not all materials are made up of molecules. Copper, for example, is made up of a single copper atom. These are called elements. Each element is a type of matter that has certain individual characteristics.

Produced By Mike Hartlen The Atom One of the basic building blocks in the universe for matter is the atom. All matter - gas, liquid, or solid - is made up of molecules or atoms joined together. These atoms are the smallest particle into which an element can be divided without losing its property

Produced By Mike Hartlen A single components atom consists of three basic items: a proton, a neutron, and an electron. Within the atom there is a Nucleus. The Nucleus contains the protons and neutrons. Orbiting around the nucleus are the electrons.

Produced By Mike Hartlen An atom is similar to a miniature solar system. As with the sun in the center of the universe, the nucleus is in the center of the atom. Protons and Neutrons are contained inside the nucleus. Orbiting around the nucleus are the electrons.

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Protons are located within the nucleus of the atom (shown in blue). Protons are positively (+) charged. Neutrons add atomic weight to an atom (shown in green). Neutrons have no electrical charge.

Produced By Mike Hartlen Electrons Electrons orbit around the nucleus of the atom. Electrons are negatively (-) charged. Since electrons are lighter than protons and are outside the nucleus, they can be easily moved from atom to atom. Normally electrons are prevented from being pulled into the atom by the forward momentum of their rotation. (centrifugal force)

Produced By Mike Hartlen Electrical Charges “Opposite” electrical charges always attract each other. So particles with opposite charges will tend to move toward each other. “LIKE” electrical charges always repel. So particles with “like” charges will move away from each other. Atoms always try to remain electrically balanced.

Produced By Mike Hartlen Balanced Atoms Atoms normally have an equal number of electrons and protons. Atoms have no electrical charge. They are electrically neutral or BALANCED.

Produced By Mike Hartlen The negative charge of the electrons will cancel the positive charge of the protons, thus balancing the charge of the atom.

Produced By Mike Hartlen Ion Particles When an atom loses or gains an electron, an imbalance occurs. The atom becomes either a positively or negatively charged particle called an ION. These unbalanced charged ION particles are responsible for electron flow (electricity). Ions will take or release an electron to become balanced again.

Produced By Mike Hartlen Ion Charge A positive (+) ION has one less electron than it has protons. A negative (-) ION has one more electron than it has protons. The positive ION attracts a negative Ion's electron to become balanced. This attraction or difference in electrical potential causes electron flow.

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Free Electrons Only the FREE ELECTRONS in the outermost shell (Valance Ring) are free to move from atom to atom. This movement is called ELECTRON FLOW.

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These FREE ELECTRONS are loosely held because of their distance from the nucleus and can easily be moved to another atom or ion.

Produced By Mike Hartlen Insulators An INSULATOR is any material that inhibits (stops) the flow of electrons (electricity). An insulator is any material with more than 4 electrons in the outer ring.

Produced By Mike Hartlen Because, atoms with 5 to 8 electrons in the outer ring are held (bound) tightly to the atom, they CANNOT be easily moved to another atom nor make room for more electrons. Insulator material includes glass, rubber, and plastic.

Produced By Mike Hartlen Conductor A CONDUCTOR is any material that easily allows electrons (electricity) to flow. A CONDUCTOR has up to 3 free electrons in the outer ring.

Produced By Mike Hartlen Because atoms with 1 to 3 electrons in the outer ring are held (bound) loosely to the atom, they can easily move to another atom or make room for more electrons. Conductor material includes copper and gold.

Produced By Mike Hartlen Semiconductors Any material with exactly 4 free electrons in the outer orbit are called SEMICONDUCTORS.

Produced By Mike Hartlen A semiconductor is neither a conductor nor an insulator. semiconductor material includes carbon, silicon, and germanium. These materials are used in the manufacturer of diodes, transistors, and integrated circuit chips.

Produced By Mike Hartlen Electricity Flow Theories The Electron Theory states that current flows from NEGATIVE to POSITIVE.

Produced By Mike Hartlen Conventional Theory States, current flows from POSITIVE to NEGATIVE.

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Voltage Voltage is the electrical force that moves electrons through a conductor. Voltage is electrical pressure also known as EMF (Electro Motive Force) that pushes electrons.

Produced By Mike Hartlen Measurement A VOLTMETER measures the voltage potential (difference) across (parallel) to the circuit. Available Pressure. Voltage can exist between two points without current flow.

Produced By Mike Hartlen Voltage Units Voltage is measured in units called VOLTS. Voltage measurements can use different prefixes such as millivolt, volt, and kilovolt.

Produced By Mike Hartlen Current (Amperes) CURRENT is the quantity or flow rate of electrons moving past a point within one second. Current flow is also known as amperage, or amps for short. Higher voltage will produce higher current flow, and lower voltage will produce lower current flow.

Produced By Mike Hartlen Measurement An AMMETER measures the quantity of current flow. Ammeters are placed in series (inline) to count the electrons passing through.

Produced By Mike Hartlen Amperage Units Current flow is measured in units called Amperes or AMPS. Amperage measurements can use different prefixes, such as micro amp, milliamp, and Amp.

Produced By Mike Hartlen Affects of Current Flow Two common effects of current flow are Heat Generation and Magnetism.

Produced By Mike Hartlen Heat Generation When current flows, heat will be generated. The higher the current flow, the greater the heat generated. An example would be a light bulb. If enough current flows across the filament, it will glow white hot and illuminate to produce light.

Produced By Mike Hartlen Electro Magnetism When current flows, a small magnetic field is created. The higher the current flow, the stronger the magnetic field. Electromagnetism principles are used in alternators, ignition systems, and other electronic devices.

Produced By Mike Hartlen Resistance Resistance is the force that reduces or stops the flow of electrons. It opposes voltage. Higher resistance will decrease the flow of electrons and lower resistance will allow more electrons to flow.

Produced By Mike Hartlen Measurement An OHMMETER measures the resistance of an electrical circuit or component. No voltage can be applied while the ohmmeter is connected, or damage to the meter will occur.

Produced By Mike Hartlen Resistance is measured in units called OHMS. Resistance measurements can use different prefixes, such as Kilo ohm and Mega ohms

Produced By Mike Hartlen Resistance Factors LENGTH of the conductor. The longer the conductor, the higher the resistance. DIAMETER of the conductor. The narrower the conductor, the higher the resistance. TEMPERATURE of the material. Depending on the material, most will increase resistance as temperature increases. PHYSICAL CONDITION (DAMAGE) to the material. Any damage will increase resistance. TYPE of MATERIAL used. Various materials have a wide range of resistances.

Produced By Mike Hartlen Types of Electricity STATIC ELECTRICITY is electricity that is standing still. Voltage potential with NO electron flow. DYNAMIC ELECTRICITY is electricity that is in motion. Voltage potential WITH electron flow. Two types of Dynamic electricity exist: Direct Current (DC) Electron Flow is in only one direction. Alternating Current (AC) Electron flow alternates and flows in both directions (back and forth).

Produced By Mike Hartlen Static Electricity Voltage potential with NO electron flow. Example: By rubbing a silk cloth on a glass rod, you physically remove electrons from the glass rod and place them on the cloth. The cloth now has a surplus of electrons (negatively charged), and the rod now has a deficiency of electrons (positively charged).

Produced By Mike Hartlen Dynamic Electricity Electricity in motion, meaning you have electrons flowing. Can be either Direct Current (DC) or Alternating Current (AC)

Produced By Mike Hartlen Direct Current Electricity with electrons flowing in only one direction is called Direct Current or D/C. D/C electrical systems are used in cars.

Produced By Mike Hartlen Alternating Current Electricity with electrons flowing back and forth, negative - positive- negative, is called Alternating Current, or A/C. The electrical appliances in your home use A/C power.

Produced By Mike Hartlen Sources of Electricity Electricity can be created by several means: Friction, Heat, Light, Pressure, Chemical Reaction, or Magnetic Action. The battery produces electricity through chemical action, and the alternator produces electricity through magnetism.

Produced By Mike Hartlen Friction creates static electricity. Heat can act upon a device called a thermo couple to create D/C. Light applied to photoelectric materials will produce D/C electricity. Chemical Reaction of certain chemicals will create electricity.