Electricity—A Useful Friend That Demands Respect
ELECTRICITY is virtually indispensable to our modern civilization. Nearly everyone makes some use of electricity every day. But due to its potential danger, it demands respect. Treated properly, electricity is an extremely useful friend. Ignore its properties, and the results can be shocking, even fatal!
In your home there are two types of electricity. The most common type comes from a power station’s generator and reaches your house by means of wires. The other type you use in your house is produced by batteries.
First, let’s talk about the generated electricity. The wires in your house carry alternating current, usually 110-120 volts or 220-250 volts or both. ‘For what reason should I care about that?’ you may ask. For one, your home appliances are designed to work only at a specific voltage, or pressure. Appliances generally have labels indicating their operating voltage. You must match the voltage of your appliance to that of the electrical outlets. If the voltage does not match, your appliance will be damaged or will not operate properly.
Also, by knowing the voltage of your appliance, you may be able to calculate the amount of current it uses in terms of amperes. Often the label on your appliance lists not only the volts but also the watts, or power, used. Some more recent appliances use the term “volt-amps” instead of watts. To calculate the amount of amperage your appliance requires, divide the watts, or volt-amps, by the volts. For example: AMPERES = WATTS, or VOLT-AMPS, divided by VOLTS.
‘Why is this information useful?’ you wonder. It is because each electrical wire in your house is designed to carry a maximum number of amperes of electricity safely. So if you decide to plug in your electric toaster and electric iron in the same outlet and at the same time, you may overload the wires. The fuse or circuit breaker in your fuse box will then abruptly stop the electricity flowing to those appliances until you correct the problem. Or much worse, if you have the wrong kind of fuse and it fails to stop the flow of electricity, the wires could become so hot that a fire could start in the walls of your house.
‘How can I know the safe amount of amperes, or current?’ you next ask. Look in your fuse box. Each fuse or circuit breaker should indicate how many amperes can safely flow through the wires to each area of your house.
Extension cords can be helpful and are often used. With some cords you can plug in as many as four items. Is it always wise to do this? No, for the same reason given for not plugging in a toaster and an iron in the same wall outlet. Too many amperes of current could be drawn, with bad results. And it is not wise to put an extension cord under a carpet where there is traffic. Why? Because in time a wire in the extension cord may get broken, causing a short circuit. Short circuits can ignite fires.
Electricity takes the path of least resistance. Water is a conductor, and so are you. So beware of standing in a wet bathtub while at the same time handling any appliance or radio that is plugged into your house current. Caution should also be exercised whenever you operate power tools, such as an electric saw or a lawn mower, out of doors. The ground connection, the third pin on the power plug, should never be cut off or otherwise defeated.
Batteries are the other source of electricity in your house. Most likely you have small ones in your camera, watch, or wall clock. Your portable radio and tape recorder also have them; so does your flashlight. If you wish to listen to music while in the bathtub, you can safely turn on a radio that is operating solely on batteries.
It is not recommended to keep dead batteries in equipment, for this could cause damage. Some batteries are rechargeable, but be careful. Some manufacturers state that their batteries may explode if recharged.
Electricity is your friend. Enjoy its many benefits, but respect it.
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Volts, Watts, Amperes
A volt is the unit of electromotive force that moves current through a wire. Simplified, voltage indicates pressure.
An ampere is the unit of electrical current; it is the amount of current flowing in a circuit. Simplified, amperes indicate rate of flow.
A watt is the unit of electrical power, the rate at which work is accomplished. Simplified, watts express the amount of power consumed by any electrical device.
To illustrate: The water used to water a garden enters the house system under pressure (voltage) from the mains. The water flows through the hose at the rate of so many gallons a minute (amperes). The amount of power (watts) used is the pressure (voltage) multiplied by the rate of flow (amperes).
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Plug Repair—How to Do It
Appliance plugs may need repair or replacement due to a broken wire. Plugs vary in design in different parts of the world, but if the plug is like the one illustrated, it is done this way:
● Push wires through plug.
● Carefully strip off about one-half inch of wire insulation with a knife.
● Tightly twist together the loose wire strands of each wire.
● Tie wires in an underwriters knot. (See illustration.) This prevents strain on wires when pulling plug from outlet.
● Pull cord until knot sits in base of plug.
● Wrap exposed end of wires around screws beneath screw heads in the same direction that screws will tighten. Ground wire should be attached to third screw.
● Tighten screws firmly into screw terminals.