Part 28

Do the fuse sizes you have written on your chart agree with the ones that are in place in the panel?

Get the right size fuses and replace any that are wrong. Make sure that you have a reserve supply of the right sizes, and that they are handy for future use.

Talk it Over With Your Parents

Do you think that your home has enough of the proper size circuits? If not, talk it over with your parents. They may want to ask an electrician to go over the wiring and make the necessary changes.

What Did You Learn?

(Underline the right answer.)

1. A (television set, radio) is very sensitive to changes in voltage.

2. Dimming lights mean (static in the wires, an electrical overload).

3. Wires that become warm from overload make it (more expensive, cheaper) to operate the equipment.

4. A home of 2,000 sq. ft. should have at least (three, four) general purpose circuits.

5. One solution to low voltage symptoms is (heavier fuses, more circuits).

6. Full capacity for a Number 14 wire circuit at 115 volts is (1725 watts, 3000 watts).

7. A room air conditioner should be on (a general purpose, an individual) circuit.

8. The purpose of a fuse is to (let you disconnect the circuit, automatically prevent overloading the circuit).

9. The right size fuse is determined by (wire size, the store where you buy it).

10. A circuit chart should give (circuit description and fuse size, the maker's name).

Demonstrations You Can Give

Ask your leader to help you plan a demonstration. You can show how lights dim when too many other appliances are connected, how a fuse protects against overloading, and the danger of using too large a fuse.

For More Information

Ask your Extension agent, power supplier, or electrician for additional help.

LESSON NO. B-15

Credit Points 4

YOU CAN MEASURE ELECTRICITY

Instruments that can detect or measure the flow of electricity have helped to make possible the wonders of electricity as we know them today.

Scientists in laboratories must have measuring devices for experiments leading to new uses of electricity. Power suppliers must have instruments that tell what the generating equipment is doing and to measure the amount of electricity being sold to users. Factories need instruments that keep tab on electrical equipment to make sure electricity is being used efficiently.

In fact, almost anywhere you find electric power at work you'll find electrical instruments--even in your home. The one you know best measures the amount of electricity used. Another, in the family car, shows whether the generator is charging the battery or if the battery is discharging.

What to Do

1. Make a simple kind of direct-current meter that will show you that there's a magnetic field around a wire carrying an electric current and that will detect a very tiny current.