Benchmark Companies Inc PO Box Aurora CO Conductors, Insulators, Semiconductors

Forward Upon completion, you will:  Be given information on Conductors  Be given information on Insulators  Be given information on Semiconductors  Be presented the information needed to complete the Exercise “ELT106 Electron Theory”  Be presented the information needed to complete the Exercise “ELT106 Conductors”

Conductors, Insulators, Semiconductors Conductors Insulators Semiconductors

Introduction In this lesson we will discuss the atomic level difference between Insulators, conductors and semiconductors. We will also explore the uses of each of these different types of elements

Conductors Electrons can flow in all matter. However, this flow is much easier through some materials than others. A good conductor is material through which electrons can easily flow with little energy applied.

Conductors There are a variety of conductors on the market.

Conductors Each size is designed for a specific purpose

Conductors Each specific purpose may required a specific type of conductor.

Conductors Metals such as copper, silver, gold, aluminum and iron are considered good conductors since they have many free electrons. +29 Cu 1 valence electron +47 Ag 1 valence electron +79 Au 1 valence electron +13 Al 3 valence electrons +26 Fe 2 valence electrons

Conductors Copper is the most commonly used conductor because it is relatively inexpensive and has good conducting ability. +29 Cu 1 valence electron +47 Ag 1 valence electron +79 Au 1 valence electron +13 Al 3 valence electrons +26 Fe 2 valence electrons

Conductors The electrical conducting properties of various materials are determined by the number of electrons in the valence shell of the atoms +29 Cu 1 valence electron +47 Ag 1 valence electron +79 Au 1 valence electron +13 Al 3 valence electrons +26 Fe 2 valence electrons

Conductors The outer shell (valence shell) never contains more than 8 electrons. Generally, a conductor has only 1,2 or 3 electrons in its outer shell. +29 Cu 1 valence electron +47 Ag 1 valence electron +79 Au 1 valence electron +13 Al 3 valence electrons +26 Fe 2 valence electrons

Conductors The electrons in these shells are held loosely and there is room for more. +29 Cu 1 valence electron +47 Ag 1 valence electron +79 Au 1 valence electron +13 Al 3 valence electrons +26 Fe 2 valence electrons

Conductors There is no such thing as an ideal conductor. In an ideal conductor there would be no resistance to electron flow. This would be ideal in electronics.

Conductors Due to physical effects of friction caused by electron movement, heat by external forces and by the structure of the conductor itself, The electron movement has some resistance.

Conductors Conductors have very low resistance. Less than 1 Ohm for 10 ft of copper is a Typical value.

Conductors Examples of wire sizes are: sizediametercmilOhms/1000 feetTyp. Current limit  22 AWG25.35 mil Amp  20 AWG31.96 mil  18 AWG40.30 mil  16 AWG50.82 mil  14 AWG64.08 mil Amp 120Volt  12 AWG80.81 mil Amp 240Volt  10 AWG101.9 mil10, Amp 120/240Volt  8 AWG128.5 mil16, Amp 120/240Volt  6 AWG162.0 mil26,  4 AWG204.3 mil41,  2 AWG257.6 mil66, Wire sizes are measured by a standard known as AWG (American Wire Gage).

Conductors Examples of wire sizes are: sizediametercmilOhms/1000 feetTyp. Current limit  22 AWG25.35 mil Amp  20 AWG31.96 mil  18 AWG40.30 mil  16 AWG50.82 mil  14 AWG64.08 mil Amp 120Volt  12 AWG80.81 mil Amp 240Volt  10 AWG101.9 mil10, Amp 120/240Volt  8 AWG128.5 mil16, Amp 120/240Volt  6 AWG162.0 mil26,  4 AWG204.3 mil41,  2 AWG257.6 mil66, Wire sizes are measured by a standard known as AWG (American Wire Gage). Diameter is measured in mils. 1 mil is equal to 1/1000 th of an inch.

Conductors Examples of wire sizes are: sizediametercmilOhms/1000 feetTyp. Current limit  22 AWG25.35 mil Amp  20 AWG31.96 mil  18 AWG40.30 mil  16 AWG50.82 mil  14 AWG64.08 mil Amp 120Volt  12 AWG80.81 mil Amp 240Volt  10 AWG101.9 mil10, Amp 120/240Volt  8 AWG128.5 mil16, Amp 120/240Volt  6 AWG162.0 mil26,  4 AWG204.3 mil41,  2 AWG257.6 mil66, Wire sizes are measured by a standard known as AWG (American Wire Gage). Diameter is measured in mils. 1 mil is equal to 1/1000 th of an inch. A circular mil is equal to 1mil 2.

Conductors Examples of wire sizes are: sizediametercmilOhms/1000 feetTyp. Current limit  22 AWG25.35 mil Amp  20 AWG31.96 mil  18 AWG40.30 mil  16 AWG50.82 mil  14 AWG64.08 mil Amp 120Volt  12 AWG80.81 mil Amp 240Volt  10 AWG101.9 mil10, Amp 120/240Volt  8 AWG128.5 mil16, Amp 120/240Volt  6 AWG162.0 mil26,  4 AWG204.3 mil41,  2 AWG257.6 mil66, Wire sizes are measured by a standard known as AWG (American Wire Gage). Diameter is measured in mils. 1 mil is equal to 1/1000 th of an inch. A circular mil is equal to 1mil 2. Typical resistance for annealed copper wire.

Conductors Examples of wire sizes are: sizediametercmilOhms/1000 feetTyp. Current limit  22 AWG25.35 mil Amp  20 AWG31.96 mil  18 AWG40.30 mil  16 AWG50.82 mil  14 AWG64.08 mil Amp 120Volt  12 AWG80.81 mil Amp 240Volt  10 AWG101.9 mil10, Amp 120/240Volt  8 AWG128.5 mil16, Amp 120/240Volt  6 AWG162.0 mil26,  4 AWG204.3 mil41,  2 AWG257.6 mil66, Wire sizes are measured by a standard known as AWG (American Wire Gage). Diameter is measured in mils. 1 mil is equal to 1/1000 th of an inch. A circular mil is equal to 1mil 2. Typical resistance for annealed copper wire. Some typical current limits for various gages of wire.

Conductors The larger the diameter of wire, the more current can be allowed to flow safely. The smaller the diameter, less current can flow safely. AWG NUMBER Approx. Cross- Sectional area AWG wire sizes Less current More current

Conductors The larger the diameter of wire, the less resistance in the conductor. The smaller the diameter, the more resistance in the conductor. AWG NUMBER Approx. Cross- Sectional area AWG wire sizes more resistance less resistance

Insulators An insulator is a material that has few, if any, free electrons and resists the flow of electrons.

Insulators Generally, insulators have full valence shells of five to eight electrons. The electrons are held tightly, the shell is fairly full and very high voltage is needed to cause any electron flow.

Insulators Some common insulators are air, glass, rubber, plastic, paper and porcelain.

Insulators Insulators are used in electric circuits to keep electrons flowing along the intended path of the circuit.

Insulators No material has been found to be a perfect insulator. Every material can be forced to permit a small flow of electrons from atom to atom if enough energy in the form of voltage is applied.

Insulators Whenever a material that is classified as an insulator is forced to pass an electric current, the insulator is said to have been broken down or ruptured.

Semiconductors A semiconductor is a material that has some characteristics of both conductors and insulators.

Semiconductors Semiconductors have a valence shell which contains 4 electrons.

Semiconductors A pure semiconductor may act as either a conductor or an insulator depending on the temperature at which operated.

Semiconductors Operated at low temperatures, it is a fairly good insulator.

Semiconductors Operated at high temperatures, it is a fairly good conductor.

Semiconductors Common examples of semiconductor materials is silicon (Si) and germanium (Ge).

Semiconductors Specially treated semiconductors are used to produce modern electronic components such as diodes, transistors and integrated circuits.

Semiconductors These semiconductors are the brains of high tech machines, driving everything from pocket calculators to cell phones.

Summary Conductors  Allow electrons to move freely  Less than 4 electrons in valence shell  Examples Copper, Silver, Gold and Iron

Summary Insulators  Electrons flow is restricted  Usually a valence shell with many electrons held tightly.  Examples Glass, Rubber, Plastic, paper and porcelain

Summary Semiconductors  Electrons flow depends on the temperature of the material Low temperature makes semiconductor an insulator. High Temperature makes semiconductor a conductor.  Has 4 valence electrons in the outer shell.  Examples of semiconductor material is silicon and germanium

End of Lesson