Plusivo DMM User manual

Mastering The Art
of Measurement
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Table of Contents
Introduction 2
1. Overview 2
2. Safety Notes 3
3. General Characteristics 3
3.1 DC Voltages (DC Volts) 3
3.2 AC Voltages (AC Volts) 3
3.3 DC Current 4
3.4 Resistance 4
3.5 Diode and Continuity Test 4
4. Reference Table 5
4.1 Table of SI Units 5
4.2 Table of Prefixes 5
5. Measurement 6
5.1 DC Voltage Measurement 6
5.2 AC Voltage Measurement 8
5.3 DC Current Measurement 10
5.4 Battery Test 13
5.5 Resistance Measurement 15
5.6 Diode Test 17
5.7 Continuity Test 19
6. Basic Concepts 21
6.1 Ohm's Law 21
6.1.1 Example 21
6.2 Joule's Law for Electrical Power 24
6.2.1 Example 24
6.3 Kirchhoff's Law 27
6.3.1 Kirchhoff's Current Law 27
6.3.2 Kirchhoff's Voltage Law 27
6.3.3 Example 28
6.4 Shunt Resistor 32
6.4.1 Example 33
6.5 Choosing the Right Resistor for an LED 35
6.5.1 Example 36
6.6 Measuring Internal Resistance of a Battery 39
6.6.1 Example 40
6.7 Testing Some Components Using Multimeter 41
6.7.1 Potentiometer Test 41
6.7.2 BJT Transistor Test 43
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Introduction
In this guide, you are going to learn how to measure DC voltage and AC voltage, DC
current, resistance, diodes, and continuity test using Digital MultiMeter (DMM).
1. Overview
The compact digital multimeter can be used to measure DC voltage and AC voltage,
DC current, resistance, diodes, continuity test, and other parameters. This multimeter is the
ideal tool for laboratories, factories, enthusiasts, and families.
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Please take the time and read these operating instructions before use and
retain them for future reference. Failure to follow these instructions may lead to serious
injury and damage to property.
2. Safety Notes
1. When measuring, do not enter a limit that exceeds the range.
2. When changing the function and range, the test leads should leave the test point.
3. In the resistance mode, please do not add voltage to the input.
In general, if something unusual happens or if you suspect that something is wrong or has
malfunctioned, do not do anything with the product and immediately contact the seller for
assistance (email address: of[email protected])
3. General Characteristics
- Maximum display value: 1999 (31/2) bit, automatic polarity display
- Sampling rate: about 3 times per second
- Over range indication: the highest bit is "1"
- Low voltage display: " " symbol appears
- Working environment: (0~40) °C, relative humidity < 80%
- Power: 3 V battery (2 x AAA)
- Accuracy: ± (reading % + the least significant digits)
- Ambient temperature: (23±5) °C, relative humidity < 75%, calibration guarantee period for
one year from the day of production.
3.1 DC Voltages (DC Volts)
Range
Accuracy
Resolution Ration
200 mV
±(0.5% + 4)
100 μV
2 V
1 mV
20 V
10 mV
200 V
100 mV
600 V
±(1.0% + 5)
1 V
Input impedance: 1 MΩ
3.2 AC Voltages (AC Volts)
Range
Accuracy
Resolution Ration
200 V
±(1.2% + 10)
100 mV
600 V
1 V
Input impedance: 1 MΩ
Frequency response: (40~200) Hz
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3.3 DC Current
Range
Accuracy
Resolution Ration
2 mA
±(1.5% + 3)
1 μA
20 mA
10 μA
200 mA
100 μA
10A
±(2.0% + 5)
10 mA
Maximum input current: 10 A (not more than 10 seconds)
Overload protection: 0.2 A / 250 V fuse (10 A range is without insurance)
3.4 Resistance
Range
Accuracy
Resolution Ration
200 Ω
±(1.0% + 5)
0.1 Ω
2 kΩ
±(0.8% + 3)
1 Ω
20 kΩ
10 Ω
200 kΩ
100 Ω
2 MΩ
±(1.0% + 15)
1 kΩ
Overload protection: 250 V DC and AC peak
3.5 Diode and Continuity Test
Range
Display
Test Conditions
The diode forward voltage
DC current is about 1 mA
Reverse voltage: 3 V
Buzzer sound Test
Resistance smaller than (20
±1) Ω
Circuit starting voltage:
about 3 V
Overload Protection: 250 V DC or AC peak
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4. Reference Table
4.1 Table of SI Units
Quantity
SI Unit
Abbreviation
Voltage
Volts
V
Current
Ampere
A
Power
Watt
W
Energy
Joule
J
Electric charge
Coulomb
C
Resistance
Ohm
Ω
Capacitance
Farad
F
Inductance
Henry
H
Frequency
Hertz
Hz
4.2 Table of Prefixes
Prefix
Power
Numeric Representation
Tera (T)
1012
1 trillion
Giga (G)
109
1 billion
Mega (M)
106
1 million
Kilo (k)
103
1 thousand
No prefix
100
1 unit
Milli (m)
10−3
1 thousandth
Micro (μ)
10−6
1 millionth
Nano (n)
10−9
1 billionth
Pico (p)
10−12
1 trillionth
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5. Measurement
5.1 DC Voltage Measurement
1. Insert the black wire to "COM" and the red wire to the "V/Ω" port;
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2. Put the range switch to the corresponding DC voltage range and then put the test probes
to the source to be measured. The polarity will be shown on the display.
Figure 1. The measured voltage in this figure is 12.35 V DC.
Figure 2. The measured voltage in this figure is 4.71 V DC.
Note:
1. If the range of the voltage to be measured is unknown, put the range switch to the highest
rank, then according to the value displayed, turn to the corresponding range
2. If on the display is shown "1", this means that the range is exceeded and the range switch
must be set to a higher gear
3. Do not measure a voltage over 600 V, because there is a risk to damage the instrument
circuit
4. When measuring a high voltage circuit, pay attention not to touch any high voltage part of
the circuit.
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5.2 AC Voltage Measurement
1. Insert the black probe to "COM" and the red probe to "V/Ω";
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2. Put the range switch to the corresponding ACV range and then put the test probes to the
source to be measured.
Figure 3. The measured voltage in this figure is 240 V AC.
Note:
1. If the range of the voltage to be measured is unknown, put the range switch to the highest
rank, then according to the value displayed, turn to the corresponding range
2. If on the display is shown "1", this means that the range is exceeded and the range switch
must be set to a higher gear
3. Do not measure a voltage over 600 Vrms, because there is a risk to damage the
instrument circuit
4. When measuring a high voltage circuit, pay attention not to touch any high voltage part of
the circuit.
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5.3 DC Current Measurement
1. Insert the black probe to "COM". The red probe can be inserted to "V/Ω" for measuring up
to 200 mA, or insert the red probe to "10 A" for a maximum 10 A measurement.
For 200 mA or less, you can set-up the probes of the multimeter like this:
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For 200 mA to 10 A, the red probe should be inserted to the 10 A DC port. Please see
below.
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2. Put the range switch to the corresponding DC current range (Figure 4 is set at 200 mA
and Figure 5 is set at 10 A) and then put the multimeter (the 2 probes) in series with the part
of the circuit that you want to measure how much current it draws. The polarity will be shown
on the display.
Figure 4. The measured current in this figure is 129.8 mA.
Figure 5. The measured current in this figure is 3.07 A.
Note:
1. If the range of the current to be measured is unknown, put the range switch to the highest
rank, then according to the value displayed, turn to the corresponding range.
2. If the display is shown "1", this means that the range exceeded and the range switch must
be set to a higher gear.
3. The maximum input current is 200 mA or 10 A (depending on the port that the red probe
was inserted). If you try to measure a current higher than the maximum input specifications,
the fuse will blow. Check the fuse if you have no reading on the display.
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5.4 Battery Test
1. Insert the black wire to "COM" and the red wire to the "V/Ω" port;
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2. Put the range switch to the corresponding Battery you want to measure. The polarity will
be shown on the display.
For the 1.5 V battery test, there is a 40 ohm-resistor test load that is included internally in the
multimeter. What the screen shows is the current flow in mA, the higher current you get, the
stronger battery you have.
Figure 6. The measured current in this figure is 38.4 mA.
For the 9 V battery test, there is a 400 ohm-resistor test load that is included internally in the
multimeter. What the screen shows is the current flow in mA, the higher current you get, the
stronger battery you have.
Figure 7. The measured current in this figure is 21 mA.
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5.5 Resistance Measurement
1. Insert the black wire to "COM" and the red wire to the "V/Ω" port;
2. Put the range switch to the corresponding resistor range and connect the two test probes
to the element you want to measure.
Figure 8. The measured resistance in this figure is 9.89 kΩ.
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Figure 9. The measured resistance in this figure is 6.2 Ω.
Note:
1. If the resistance value exceeds the selected range value, on the display will be shown "1"
and the range switch should be changed to a higher gear. When the measured resistance
value is more than 1 MΩ, the reading takes a few seconds to stabilize, which in high
resistance mode is normal.
2. When the input is open, the overload condition is displayed.
3. When measuring the on-line resistance, make sure that all the power of the circuit under
test is turned off and all the capacitors are fully discharged.
4. Do not input voltage in the resistance range.
5. Do not touch the two test probes at the same time, because the resistance of your body
will be added in parallel to the resistance that you want to measure.
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5.6 Diode Test
1. Insert the black probe to "COM" and the red probe to "V/Ω" (note that the polarity of the
red probe is "+").
2. Put the range switch to " ". Connect the black probe to the cathode and the red probe
to the anode.
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The display will show the approximate forward voltage drop.
Figure 10. The measured forward voltage in this figure is 0.683 V.
Figure 11. If you connect the probes incorrectly, the display will show "1".
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5.7 Continuity Test
1. Insert the black probe to "COM" and the red probe to "V/Ω"
2. Put the range switch to " ". Connect the probes to the circuit or the component you
want to test the conductivity for it.
If a conductor path is connected, the multimeter will beep, the display will show the
resistance of the circuit or the component.
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