Circuits at Home

(Are You Plugged into Electric Safety?)

5.0 Circuit Connections at Home

5.1 Kinds of Circuits at Home:

Fact: there are two kinds of circuits series and parallel (Review pp ______)

Parallel, many path,:

These circuits are used for convenience. These circuits allow you to use one appliance while another in the same circuit is turned off.

These circuits are a safety problem if they are are over used.

(The current in each path adds to the current in the whole circuit 120 W appliance use at at 120V = 1A)

Series, single path:

These circuits are used for safety protection or switching,.

They use switches, breakers, or fuses to turn off other larger circuits (which may have many paths).

1) Evaluate the safety hazard, if there is any, in operating of the following circuits. Check out the following circuits

Trace with a red marker the part of the circuit which can be overloaded by using only the plugs pictured with 120W(1A appliances).

 

 

 

 

.11 Circuit Materials

Which materials can be used to make good wires?

(Are there any surprises)

Diagram: Circuit Tester

 

 

 

Test Object

Prediction

Conductor

 

Prediction

Insulator

Tested as

either

conductor

or

Insulator

       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       

Are there any surprises? Explain

__________________________________________________________________________________________________________________________________________________________________

5.20 Plugged into Safety

Plug the appliances in so they do not overload the circuits

.

Plug in an appliance load from the choices at the left. (Be careful not to blow the fuse)

Draw a cord from the appliance to the plug

 

 

 

 

 

 

 

 

Trace in red the circuits which are not protected by the breakers or fuses designed to protect them. (Make the correction by placing a 15A fuse in the unprotected path.)

 

 

 

 

 

 

 

5.20 Plugged Into Safety

Cryptogram Key

a b c d e f g h i j k l m

a b c d e f g h i j k l m

n o pq r s t u v w x y z

 

Decode the following electrical safety hazards:

a) prying out caught toast while the toaster is plugged in.

 

b) wet hands on anything

electrical .

 

c) flying kites near electrical wires.

 

d) playing games near light &power electrical equipment.

 

e) worn wires or cords

needing repair.

 

f) throwing water on electrical fires.

 

g) careless mixing of water metal and

electricity

 

h) fallen power lines

 

i) getting out of a car accident where power lines are contacted.

j) climbing or cutting a tree near power lines

 

k) pushing or climbing on

a fallen tree leaning on power lines

 

l) flying a kite with wet string, fishing line or fine wire

 

m) standing under a tree during electrical storms

 

n) bringing electrical

appliances near water.

 

o) attempting a pet rescue from electric

power poles.

 

p) walking near fallen power lines.

 

q) placing an electrical cord under a rug.

 

r) using an electric appliance, like an electric lawn mower, on

wet grass

 

s) using masking tape to repair worn or

bare wires.

 

t) using octopus connections or more than one plug bar.

u) repairing an electrical appliance which is

plugged in

Answers: 5.20 Plugged Into Safety

a) prying out caught toast while the toaster is plugged in.

b) wet hands on anything electrical .

c) flying kites near electrical wires.

d) playing games near light &power electrical equipment.

e) worn wires or cords needing repair.

f) throwing water on electrical fires.

g) careless mixing of water metal and electricity

h) fallen power lines

i) getting out of a car accident where power lines are contacted.

j) climbing or cutting a tree near power lines

k) pushing or climbing on a fallen tree leaning on power lines

l) flying a kite with wet string, fishing line or fine wire

m) standing under a tree during electrical storms

n) bringing electrical appliances near water.

o)attempting a pet rescue from electric power poles.

p) walking near fallen power lines.

q) placing an electrical cord under a rug.

r) using an electric appliance, like an electric lawn mower, on wet grass

s) using masking tape to repair worn or bare wires.

t) using octopus connections or more than one plug bar.

u) repairing an electrical appliance which is plugged in

.21 Electrical Safety Puzzle-1

Note:(poster safety/ conductors insulators)

Words

Write the words in the boxes on the light bulb.

safety

conductor

appliances

antennas

current

electricity

kite

water

.22 Electrical Safety Puzzle-2

Note:(poster safety/ conductors insulators)

Unscramble the Words

Write the words in the boxes on the light bulb.

teyfas

urtocondc

lapiapnecs

nteannsa

rrcunet

ictrelicyt

itek

twear

 

Electrical Safety Puzzle-3

Word Choices

damp metal fence

plug fuse water

toast radio glass

lines hydro shock

kite outlet safety

conductors electricity insulator

Across

1. __________ is a useful servant, but must be used properly.

5. You could get a severe __________ by touching a plugged in appliance with wet hands.

7. Never use an electric lawn mower on ________ grass. (not even on slightly wet grass)

8. Pull the __________ not the cord.

10 The inside of an electrical cord is made out of __________.

11. Don't pry __________ from a plugged in toaster.

13. Never touch a fallen electrical __________

16. Plugging several cords into one __________ is a fire hazard.

17 Climbing a __________ around a substation is dangerous.

18. If you are in a car that has come into contact with fallen power lines from a __________ pole, stay in the car until help comes.

 

Down:

2. Plant trees clear of power __________

3. __________ permit the flow of electricity.

4. Wood is a good __________. (if dry, not green)

6. Always fly your __________ away from power lines.

9. __________ is an excellent insulator commonly used in windows

12 Electrical __________ can save lives and prevent injuries..

13. Electricity + __________ = danger

14. A television or a __________ should never be placed by a swimming pool or a hot tub.

15 Always replace a __________ with another of the same size.(15A for household circuits)