Digital Multimeter

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Forging new generations of engineers
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Digital Multimeter
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What is a Digital Multimeter?

• A digital multimeter is highly accurate and
  provides LCD number readouts. It can easily
  measure AC / DC voltage, resistance, and current.

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Test Leads
Test leads are used to connect the multimeter to
the circuit to be tested.
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Function/Range Switch
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Voltage Meter

• The volt meter is used to measure the voltage
  potential across a component in an active
  circuit.
• Can be used to measure either DC or AC voltages.
• AC voltage can ONLY measure sinusoidal (SINE)
  waveforms.

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Test Lead Connections - Voltage

• Plug the RED test lead into the jack labeled V/?
  and the BLACK test lead into the jack labeled COM
  (common).

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Ohm Meter
The ohm meter is used to measure the resistance
of a component. NO POWER can applied to the
component being tested. The ohm meter actually
applies a small voltage and uses ohms law to
calculate the resistance from the measured
current.
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Test Lead Connections - Resistance

• Same As Voltage Measurement

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Ampere Meter
The amp meter is used to measure the current
through a component in an active circuit. Can
be used to measure only DC current. Some
multimeters can also measure AC current
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Test Lead Connections - Current

• Plug the RED test lead into the jack labeled mA
  for milliamps or into the jack labeled 10A for
  circuits with high current levels. Plug the
  BLACK test lead into the jack labeled COM.
• Be certain to select the range according to the
  test lead connections.
• Observe proper polarity.

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Basic Instructions

• Be sure the test leads are connected properly for
  measurement being made.
• Turn the meters Function/Range switch to the
  function (ACV, DCV, DCA or ?) setting you are
  measuring.
• Select at a range which is higher than the
  expected value.
• Connect the test leads to the circuit/component
  begin tested. Observe proper polarity.
• Turn the meters Function/Range switch to reduce
  the range and increase the accuracy.
• Record results.
• Remember to turn the power OFF.

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Special Functions
Continuity Tester Used to test the continuity
between two points. Will produce an audio
tone. Diode Tester Used to test the resistance in
a diode for forward bias and reverse
bias. Battery Tester Used to test 9 volt and 1.5
volts (AAA,AA, C, D) batteries.
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If the Meter Malfunctions

• Check battery.
• Review instructions to make sure you are doing it
  properly.
• See if test leads are broken or not connected
  properly.
• Inspect and test the fuse.