AT 121
Electrical and Electronics Systems

Mr. Reed
Monday and Wednesday
8:30 - 11:30
Syllabus Review
•	Electrical is the “foundation” for all the other classes.
•	Needed for Heating and Air cond, Advanced brakes, Advanced Electrical, and Engine Performance classes.
What are we going to do?
•	Learn how circuits work
•	Build Circuits
•	Use test equipment
•	Read electrical schematics (diagrams)
•	Test/Inspect/Lean about
–	Batteries
–	Starting Systems
–	Charging System
“The Car Won’t Start”
•	Well, its really a “no crank”
•	No Start – AT 261 class issue
•	Fuses
•	Battery
•	Battery Connections
•	Starter and Starter Ckt.
•	Alternator?  Is it working?!?!
How to do well in this class?
1 - Show up on time
•	Often, late in the semester people show up late at the start of class.
•	Missing Class impacts your grade as much as a test does.
•	Time *is* an issue.  We have a lot of ground to cover.
•	Most of the lab work is done in groups and students have a _very_ hard time making up missed labs on their own!
2 - Do the work in the class.
•	Do it well
•	Don’t play on the web…
•	Work with fellow students (yes, there will be a project…)
•	Work on the labs.. Not with your hands in your pockets
•	Fill out the labs - fully
•	Work safe - a MUST!
3 - Do the work OUTSIDE of class
•	Homework - MUST be typed.  No exceptions.
–	Counts as much as a test grade
•	E-mail - MyCCP (only!)
•	My website
•	Office Hours - 
•	Ford Tech Service. 
–	Counts as much as a test grade
All must be done on time!!
4 - Study
•	No Music
•	No IMs\Chat
•	No WEB
•	No Cell Phone
•	Eat sometime, have something to drink
•	Find a quiet place to work
•	“Two hours for every hour of class”
Hours
•	There are 168 hours in a week
•	You need (8 hours to sleep) – 56hrs
•	6 hours of this class per week
•	I’d say that you could spend up to an extra 12 hours a week for out of class.
•	Use your time wisely.
Grades
•	..\fall2005files\samplegradesheet.xls
Safety Factors Needed When working on vehicles;
•	1 - Running Engines put out toxic gases

•	HC (Gasoline)
•	CO (Carbon Monoxide)
•	Nox (Oxides of Nitrogen)

•	Cars MUST be hooked up to the exhaust system

•	2 - Moving objects and tools.

•	Safety Glasses

•	Oil, Gasoline (under pressure up to 100 PSI), compressed air.
•	Belts, coolant overflow

•	3 - Hot engine parts.

•	Exhaust manifolds - 600 deg.
•	Intake manifolds - 200 deg.
•	Catalytic Converter - 1500 deg.
•	Cooling System components - 220 deg.
Break.
Electricity?
•	Difficult to see with the naked eye
•	(sparks, lightning, arcs)

•	Easy to Measure with tools;
•	Digital Multi Meter or Digital Volt Ohm Meter
•	(DMM/DVOM)
Powers "everything"
•	Cars, Homes, Trucks, Computers, Power Plants, 
•	Medical Equipment, Clocks, Heating and Cooling Systems
•	Lights, and Communications!
•	Backbone of modern society!
•	Modern useful skill!! Homes/Cars
Atoms
•	Smallest part of a chemical element
•	Several atoms make up a molecule
•	H - Atom (Hydrogen)
•	O - Atom (Oxygen)
•	Add H and 2 Os and you get a molecule of H2O!
•	A copper wire holds Billions of copper atoms!
Atomic Structure
•	Electrons (-) - Circle in A "ring" around Protons and Neutrons
•	Protons (+) / Neutrons - Center of atom - called a Nucleus
•	Valence Ring - Outermost ring of an Atom

•	Atoms that can transfer "spare" electrons to and from their valence rings are called conductors
•	Atoms that cannot transfer "spare" electrons to and from their valence rings are called insulators

Balanced Atoms
•	Atoms seek to be "balanced"  - Have an equal number of Electrons in its Valance Ring.
•	Copper - Normally has two Electrons, but it *can* hold up to three

•	Copper Atom 1 - Has only 1 electron, so it *steals* 1 electron from another atom with 3 electrons!
•	OR
•	Copper Atom 2 - Has 3 electrons, and it wants to loose 1 - so it gives it to another atom with 2 electrons!

Conductors 
•	Allow Electricity "Flow" 
•	Have three or less electrons, and they like to transfer!
•	Most Metals; Copper, Gold, Silver, Nickel
•	Water
•	Why?  Because they can transfer Electrons!
Insulators
•	Resist Electricity "Flow"
•	Have five or more electrons, and do NOT like to transfer!
•	Plastic, Glass, Air, Wood, Concrete
•	Cannot transfer electrons!
Electricity;
•	*IS* the movement of electrons!
•	Must be "pushed" by EMF;
•	Electro Motive Force

•	Protons at one end of circuit (+)
•	Electrons at other end of circuit (-)

•	The electrons are attracted to the protons

•	This causes atoms to transfer electrons to and from each other - but always in the *same* direction!
Homework…
•	1 – Get the book.
•	2 – Read Chapter 3
•	3 – Send me e-mail. from your MYCCP account!