2. A. What is Electricity?
1. Electricity is the flow
of minute charged
particles of energy
through conductors,
such as wires.
2. What does each color
mean?
a. Black: “hot”
b. White: Neutral/return
c. Green: ground wire
3. B. What does that mean????
1. Black: This wire carries electricity away from the
power source and to the device receiving power.
2. White: Returns power back to the power
source…your breaker box.
a. Once the current reaches the breaker box we have a
complete circuit.
3. Ground: a safe alternative pathway for the
electricity to return to the power source if at any
time an accident were to occur. (can be green or
bare)
4. MAKE A CIRUIT LAB
**we discussed circuits in the intro to electricity notes
1. Each group will be given
a. 2 D batteries
b. 2 wires
c. One bulb (from a flashlight)
d. Tape
2. Students need to make:
a. 1 functioning series circuit
b. 1 functioning parallel circuit.
5. C. HOW DOES POWER GET TO MY HOUSE??
D. Power Stations: produce the electricity.
1. High Power Lines: transport electricity to a
substation at a very high voltage (deadly!!)
2. Transformers convert this energy into 120 and
240 volts for use in the home.
3. Electricity enters home from a transformer to
your service panel (outside your home)
4. Your circuit breaker distributes the electricity into
your home on individual ciruits.
6. D. SERVICE PANELS
1. Older homes have fuse
boxes instead….
2. These boxes are fed
with 240 volts of
electricity from a
transformer!!!
3. We will not practice
installing new breakers
for obvious reasons!!!
7. E. WHAT IS A CIRCUIT BREAKER
1. A circuit breaker is a device that electricity will
pass through directly before it is delivered
throughout the home.
a. Can be 15, 20, 30, and even 50 amp breakers.
2. Function: to sustain the proper amount of
current running into your home for the devices
connected on that circuit.
a. Will trip/open when to many amps are being drawn.
b. Designed to prevent fires and electrical
injuries/tragedies.
9. F. What is the purpose of a breaker?
1. A circuit breaker is designed to “trip” or shut
itself off when it detects a fault current on the
circuit.
1. It is important that we only have the appropriate
amount of current running through a circuit to meet
our household.
2. On/Off/Tripped:
a. Depending on the manufacturer the breaker will either
display an orange/red indicator of will flip somewhere into
the off position when tripped.
3. **Think about the name…Ciruit….Breaker…..
10. G. What to do if a breaker trips
1. Investigate what on that circuit caused the
breaker to trip.
a. Is the circuit overloaded (to many items plugged
in to the outlet)
b. Did water come in contact with the breaker?
c. Is there a wire or wires that have been cut/frayed
by something that causes a short?
11. H. What wire to choose????
1. Types of wire we will discuss:
a. Interior wire
b. Direct burial outdoor wire
c. 12-2 and 14-2 (indoor and outdoor)
2. Other types we won’t have time to go into
detail
a. 12-3: This wire has 3 conductors and a
ground….12-2 has only 2 conductors and a
ground.
13. J. What does the gauge of the wire
mean??
1. The smaller the gauge number….the thicker the
wire.
a. 10 gauge is thicker than 12 gauge….and 12 gauge is
thicker than 14.
b. The thicker the wire…the more current it can take
without heating up.
i. Most 120 volt household wires are 10, 12, or 14 gauge.
2. On the outside of the cable there is a description
of the gauge and the number of conductors.
14. K. Color coding of wires
1. This is a general rule…but def. not a law to
live by!!!
a. 14 gauge wire is generally white (indoor)
b. 12 gauge wire is generally yellow (indoor)
c. 10 gauge wire is generally orange (indoor)
d. MOST outdoor wire is gray….outdoor wire each
wire inside is coated individually…you will see
when we practice stripping it!!!!!
i. Why would outdoor wire have more coating??
15. L. Amperage and Wires
1. Circuit breakers set the limit for how many
amps can be used in that circuit.
2. Example:
a. If an electrical device on 20 amp breaker is
drawing more than 20 amps of power, the wire
may heat up….at that point the breaker will
sense a potential dangerous situation and trip.
3. It is very important to use the correct gauge
wire!!!
16. L. Amps and wires (continued)
4. The chart below will illustrate what size wire
should be used with each size circuit breaker.
17. 5. Using a 14 gauge wire on a 20 amp breaker
may be a recipe for disaster in your home.
a. The wire may overheat…but because the current
is less than 20 amps the breaker may not
consider the overheating a dangerous situation.
b. The heat may end up causing a short circuit or
fire.
18. M. What is a short circuit?
1. Most short circuits occur when a “hot” wire and
a neutral or ground come into contact some
unintended way.
a. Most of the current in these cases will continue back
to the ground using the neutral wire instead of
continuing on its intended path.
b. In this case heat builds up very quickly because the
current has very low resistance.
c. A working breaker should sense this fault and trip.
d. Most short circuits occur due to faulty wiring or bad
connections!!!
19. N. AMPS VOLTS AND WATTS
1. Amps: measure the volume of the electricity;
or the amount of electrons passing a given point
every second.
2. Volts: measures the pressure or the force under
which electricity moves.
a. Power companies provide homes with electricity
pressure of 120 or 240 volts.
3. Watts: what we use to measure electrical
power or the measurement of the total amount
of electricity used.
a. Watts= Volts X Amps
20. Connecting your outlets !!!
1. Your completed outlet must be wired to
another persons completed outlet.
a. **you must remove the ground from the outlets.
b. Grounds are then “sistered” or twisted together
then put on as one ground screw.
i. There will be a demonstration!
