Digital multimeter

1. Directorate of Technical
Education,
Tamilnadu.
Thanthai Periyar Government
Institute of Technology,
Vellore–632002
Department of ECE

2. Digital Multimeter
Unit 5
Presented by
Mrs.M.P.Sasirekha

3. Contents
• Definition
• DMM
• Parts of Digital Multimeter
• Features
• Block diagram
• Measurement – voltage , Resistance , Diode ,
current .
• Manufacturers
• Reference
• Thank you

4. Definition
• Digital multimeter is a test equipment which
offers several electronic measurement task in one
tool. It is also known as the voltmeter or Ohm
meter or Volt Ohm meter.
• The standard and basic measurements performed
by multimeter are the measurements of amps,
volts, and ohms. Apart from that, these digital
multimeters perform many additional
measurements by using digital and logic
technology. These may include temperature,
frequency, continuity, capacitance etc.
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5. DMM
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6. Parts of Digital Multimeter
• A multimeter is a simple but useful device
which has only three parts
• Display screen
• Selection knob
• Ports.
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7. Display screen
• Display screen-It has illuminated display
screen for better visualization.
• It has five digits display screen; one represent
sign value and the other four are for number
representation.
NextDiagram

8. Selection knob
• Selection knob
• As we know a single multimeter performs so
many tasks like reading voltage, resistance,
and current.
• The selection knob allows the user to select
the different job.
NextDiagram

9. Port
• Port- There are two ports on the front of the unit.
One is the mAVΩ port which allows the
measurement of all the three units: current up to
200 mA, voltage, and resistance. The red probe is
plugged into this port.
• The other is COM port which means common and
it normally connected to –ev of a circuit and black
probe is plugged into it. There is one particular
port is 10A, which is use to measures large
current in the circuit.
NextDiagram

10. Ports
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11. Features of Digital Multimeter
• Auto-Rang
• A Back-Lit LCD
• Auto-Off
• Decent Probes
• Auto Polarity
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12. Block diagram
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13. Voltage Measurement by Using a
Digital Multimeter
• When set to measure the voltage, the
multimeter acts like a voltmeter.
• To start with, one has to insert the red and the
black probes of the multimeter to the sockets
marked as ‘V’ and ‘COM’, respectively.
• Then we have to select the expected range in
which our voltage would be. Simultaneously,
even AC or DC should also be selected in the
voltmeter section of Figure .
Diagram Next

14. Diagram
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15. Resistance Measurement by Using a
Digital Multimeter
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16. Diode Check by Using a Digital
Multimeter
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17. Current Measurement
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18. Reference
• https://www.electrical4u.com/digital-
multimeter/
• https://www.electrical4u.com/how-to-use-a-
digital-multimeter/
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19. Different Manufacturers
• https://www.google.com/search?sxsrf=ALeKk
03rVR3G0cnJ7YXpbNeSgB6q3voFBA:1589153
833298&q=types+of+manufacturers+of+DIGIT
AL+MULTIMETER&spell=1&sa=X&ved=2ahUKE
wi9jOitu6rpAhUBxDgGHc_IARgQBSgAegQIDh
An&biw=1356&bih=645
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20. Thank you