  Credit Points 4 READING THE ELECTRIC METERThere is no question but what electricity is one of the lowest cost services in the home and on the farm. A few pennies worth of electricity will provide the power to run machines that take the place of a man or of several men working all day. However, we all like to know what things cost. Sometime you may have to decide between different methods—man, horse, gasoline engine or electric motor power. Then you'll want to know how to figure the cost of electricity, as well as the cost of the original equipment. First of all, you should know how to read an electric meter. Reading a MeterElectric meters read in kilowatt hours, just as a water meter reads in gallons and a gas meter in cubic feet. A kilowatt hour is the electrical energy consumed by 1000 watts of electricity used for one hour. Ten 100-watt light bulbs burning for one hour would use one kilowatt-hour—one kwh. Figure 1. Some meters give the reading directly, like the mileage total on a speedometer. Some meters are read directly, as shown in Figure 1. The more common type has four dials which are read from right to left—just the opposite from the way things are usually read. The hand on the extreme right turns clockwise, the next hand turns counter-clockwise, the next clockwise; the last hand on the left turns counter-clockwise. The first dial on the right can register up to 10 kilowatt-hours; the second up to 100 kwh; the third, to 1000 kwh; the fourth, to 10,000 kwh. After that, the meter starts over again. To take a reading you must read all four dials of the meter, from right to left. Figure 2. Meter dials are read from right to left. To read each dial, you use the number last passed by the dial hand. This may not be nearest the hand. For instance, if the pointer has passed 6 and is almost on 7, you read it as 6. Write down the figures in the same order you read the dial, from right to left. Practice reading the meters shown in Figure 3 on the following page. What's Your Electric Bill?Meters aren't set back each month when the meter reader comes around. The difference Figure 3. See if you can read the above correctly. The answers are shown in a box on the next page. It will be interesting to you to find out how much it costs to operate the various electric appliances in your home. A sample rate schedule is shown in Figure 4. Figure 4. Sample rate schedule. Note that as the use of electricity increases, the average cost per kwh is reduced. Estimating Operating CostsTo find the cost of operating any single appliance, three steps are necessary: 1. Learn the wattage of the appliance. 2. Estimate how many hours the appliance is used. 3. Find its operating cost. To Find Wattage: Watts, you know, are the measure of electrical power. They are the product of voltage (pressure) times amperes (rate of flow). Volts times Amps equals Watts. The nameplate on the appliance will give the voltage required for proper operation as well as either amperage or watts. If it gives wattage, you have the information you want. Otherwise you must multiply volts times amps to get the wattage. When voltage is given as 110-120, use 120 as your voltage. 120 volts is nominal today. How Much Will You Use? Now that you know the wattage of the appliance, multiply this figure by number of hours the equipment operates in one day. Divide this by 1000 to get the kwh. Now multiply the result by the number of days the appliance is used each month. This tells you the number of kwh used by the appliance during the month. Example No. 1 Yard Light:300-watt lamp Example No. 2 Coffee Maker: 120 volts, 550 watts (from nameplate) Calculate Operating Cost Per Month Now that you know the number of kilowatt hours an appliance uses, go to your rate schedule and your electric bill to see what the average kwh costs. Find the average cost of 1 kwh by dividing the amount of your bill by the total number of kwh used in a month. Example: 410 kwh used. Therefore, the cost of operating the coffee maker for a month would be 3-1/2 cents times 7.25 kwh—25.4 or 25 cents. Cost of operating the yard light would have been 94.5 or 95 cents a month. (a) 6357nbsp;(b) 1963(c) 8996 Adding Low Cost HelpersYou can see, by looking at your rate schedule, that the average cost per kwh gets lower as you use more electricity. To find the cost of operating additional electrical equipment, the cost per kilowatt hour is found from the last "step" in the bill—the lowest cost per kwh of the electricity you're now using. Sometimes power suppliers give special rates for such equipment as electric water heaters. WHAT TO DO: Find the Cost of Operating Electrical EquipmentMake and fill in the blanks of a chart showing the electrical equipment you have and the operating costs per month. Make a chart for the home (refer to chart one). Show the probable operating cost of equipment you might add to what you now have. Demonstrations You Can GiveShow how to read a meter, making one with plywood or cardboard. Dials can be painted on the main board. Arrows can be attached so they will revolve to give different readings. Show how to find the wattage of various types of equipment. Show how to figure the cost of the average kwh in a home. For Further InformationYour leader can get additional material for you or you may want to have someone from your power supplier talk to your club, telling about meters, how they work and how they are regularly checked for accuracy. Chart One-THE HOME
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