HOLDER 1519941 - Caterpillar

Digital Multimeter
This information covers the basic functions and operation of the digital multimeter. Although an analog multimeter and test light may be used by a service technician, the digital multimeter performs the more complex measurements on the newer electronic systems. Digital multimeters use the metric system, in order to make it easier to work with large numbers.Digital Multimeter
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The digital multimeter is highly accurate. The digital multimeter is used to find the precise value of any type of voltage, current or resistance. The meter is powered by a 9 volt alkaline battery. The meter is sealed against dirt, dust, and moisture.The meter has four main areas: the liquid-crystal-display, push buttons, rotary dial function switch, and inputs for the meter leads.Liquid Crystal Display
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The meter's liquid crystal display, or LCD, uses display segments and indicators. Digital readings are displayed on a 4000 count display with polarity ( ) indication and automatic decimal point placement. When the meter is turned ON, all display segments and annunciators appear briefly during a self test. The digital display (1) updates four times per second. When frequency readings are taken. The display updates three times per second.The analog display (2) is a 32 segment pointer that updates at 40 times per second. The display segments have a pointer that rolls across the segments indicating a measurement change. The display also uses indicators to abbreviate various display modes and meter functions.Push Buttons
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The buttons on the meter are used to perform additional functions. The additional buttons will be covered later in the course as they apply to the type of measurement taken.When the meter is first switched on and a measurement is made, the meter automatically selects a range. The meter will display the word "AUTO" in the upper left corner. Pressing the range button will put the meter in manual range mode. The range scale will be displayed in the lower right corner of the meter. With each additional press of the range button, the next increment will be displayed. Press and hold the range button in order to return to the auto range mode. The yellow button can be used to backlight the meter display.Rotary Switch
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Various meter functions are selected by turning the meter's rotary switch. Each time the rotary switch is moved from OFF to a function setting, all display segments and indicators turn on as part of a self test routine. Moving clockwise from the OFF switch, the first three positions on the rotary switch are used for measuring AC voltage, DC voltage, and DC millivolts. The top position is used for measuring resistance. The next position will allow the meter to check diodes. The last two positions are used for measuring AC and DC current in amperes, milliamperes, and microamperes.Meter Lead Inputs
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Depending on the measurement that you wish to make, the meter leads must be placed in the correct terminals. Notice the insides of the input terminals are color coded, red or black. The positive lead can go