Tenma 72-8715 User manual

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Model: 72-8715
Digital Bench Multimeter

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Please read these instructions carefully before use and retain for future
reference.
• This meter is designed to meet IEC61010-1, 61010-2-032, and 61010-2-033 in
Pollution Degree 2, Measurement Category (CAT I 1000V, CAT II 600V, CAT III
300V) and double Insulation.
• When using electrical appliances basic safety precautions should always be
followed.
• Please operate according to this manual, otherwise the protection provided by the
device will be impaired or fail.
• There are no user-serviceable parts in this product. Refer servicing to qualied
personnel.
• Use only the test leads supplied or the protection may be impaired.
• Check the test leads, probe and case insulation condition before using. If you nd
any breakage, damage or abnormality, or you consider the device is broken, stop
using the device immediately.
• When using the test probes, keep your ngers behind the nger protection rings.
• Ensure all inputs are less than the range selected otherwise it may cause electrical
shock or meter damage.
• Take caution when voltages are above 60V DC and 30V AC rms.
• Do not use the meter with the battery or fuse covers removed.
• Do not adjust the range selector during measurement.
• Replace the batteries as soon as the low battery indicator appears on the display.
• Remove dead batteries from the meter or if it is not going to be used for a long
time.
• Never mix old and new batteries together, or different types of batteries.
• Never dispose of batteries in a re, or attempt to recharge ordinary batteries.
• Before replacing the battery, turn off the meter and disconnect all the test probes
• To prolong battery life turn off the meter after use.
ELECTRICAL SYMBOLS GUIDE
WHAT’S INCLUDED
• Bench type digital multimeter.
• Operating manual.
• Power supply unit.
• Alligator clips (1 pair).
• Multi purpose socket.
• Test leads (1 pair).
IMPORTANT SAFETY INFORMATION
AC or DC Ground Double insulated
Continuity test
Low batteryWarning
Capacitance testDiode test Fuse

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Range Selector Positions Function
V AC and DC voltage measurement
Continuity test
Diode test
Resistance/continuity measurement
Capacitance test
Hz Frequency measurement
FCapacitance measurement
ºC Temperature in celsius
hFE Transistor test
A AC or DC current measurement
FUNCTIONS
OPERATING PARAMETERS
UNITS OF MEASUREMENT
• Ambient temperature : 0ºC ~ 40ºC.
• Relative humidity : ≤75% @ 0ºC ~ 30ºC, ≤50% @ 30ºC ~ 40ºC
• Maximum operating altitude 2000m
• Maximum Display : Digital: 1999
• Measurement Speed : Updates 2-3 times/second
• Polarity display : Automatic
Ω
Function buttons Operation performed
POWER Turn the power on and off
LIGHT Turn display back light on and off
HOLD To enter or exit range hold in any mode
mV,V Unit of Voltage: The millivolt, volt
μA,mA,A Unit of current: Microampere, milliampere, ampere
Ω,kΩ,MΩ Unit of electrical resistance: Ohm, thousand ohms, trillion ohm
nF,μF Unit of electrical capacity: Accepts the farad, the microfarad
kHz Unit of Frequency: Kilohertz
OC Unit of Temperature: Degree Celsius
βFactor Unit of Triode enlargement: Times

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LCD Display Range Selector
Hold Button
Input Terminals
Light Button
Power Button
Symbol Terminal input Explanation
VV ←→ COM DC Voltage Measurement
V~ V ←→ COM AC Voltage Measurement
Ω V ←→ COM Resistance Measurement
V ←→ COM Diode / Continuity Buzzer Measurement
kHz V ←→ COM Frequency Measurement
AmA μA ←→ COM mA/μA DC Current Measurement
10A ←→ COM A DC Current Measurement
A~ mA μA ←→ COM mA/μA AC Current Measurement
10A ←→ COM A AC Current Measurement
FV ←→ mA μA
(Use Multi-Purpose Socket) Capacitance Measurement
ºC V ←→ mA μA
(Use Multi-Purpose Socket) Temperature Measurement
hFE V ←→ mA μA
(Use Multi-Purpose Socket) Triode Enlargement Factor Measurement

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OPERATION
DC or AC Voltage Measurement
Warning: To avoid personal injury, or damage to the meter from electric shock, please
do not attempt to measure voltages higher than 1000V although readings may be
obtained.
To measure DC/AC voltage, connect the meter as follows:
• Insert the red test lead into the V terminal and the black test lead into the COM
terminal.
• Set the rotary switch to V to select DC measurement mode.
• Set the rotary switch to V~ to select AC measurement mode.
• Connect the test leads across with the object being measured. The measured
value shows on the display.
• When DC/AC voltage measurement has been completed, disconnect the
connection between the test leads and the circuit under test.
Note: In each range, the meter has an input impedance of 10M Ω . This loading effect
can cause measurement errors in high impedance circuits. If the circuit impedance is
less than or equal to 10k Ω , the error is negligible (0.1% or less).
DC or AC Current Measurement
Warning: Before connecting the meter in series with the circuit under test, be sure
power the circuit is off. If the fuse burns out during measurement, the meter may be
damaged and there is risk of personal injury to the operator.
Use correct terminals, function, and range for the measurement. When the test leads
are connected to the current terminals, do not connect in parallel across any circuit.
To measure current, do the following:
• Insert the red test lead into the mA μA terminal and the black test lead into the
COM terminal.
• Set the rotary switch to an appropriate measurement position in μA , mA or
A to select AC or DC measurement mode.
• Connect the test leads in series with the object being measured. The measured
value shows on the display.
Note: If the value of current to be measured is unknown, use the maximum
measurement position, and reduce the range step by step until a satisfactory reading is
obtained.
• When current measurement is complete, disconnect the test leads from the circuit
under test.

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Measuring Resistance.
To measure resistance, connect the meter as follows:
• Insert the red test lead into the Ω terminal and the black test lead into the COM
terminal.
• Set the rotary switch to select Ω measurement mode.
• Connect the test leads across with the object being measured. The measured
value shows on the display.
Note: When measuring low resistances, the test leads and internal wiring will add
approximately 0.1 ~ 0.2 Ω of error. To obtain accurate readings in low-resistance, short-
circuit the test lead beforehand and record the reading obtained, call this reading as
X. Then use the equation: measured resistance value (Y) – (X) = accurate readings of
resistance.
• If reading with shorted test leads is not < 0.2 Ω , check for loose test leads or
possible incorrect function selection.
• When measuring high resistance (>1M Ω ), it is normal to take several seconds to
obtain a stable reading.
• The LCD displays OL indicating open-circuit or the resistor value is higher than the
maximum range of the meter.
• When resistance measurement has been completed, disconnect the connection
between the test leads and the circuit under test.
Continuity Test
To test for continuity, connect the meter as below:
• Insert the red test lead into the Ω terminal and the black test lead into the COM
terminal.
• Set the rotary switch to to select continuity measurement mode.
• Connect the test lead across with the object being measured. The buzzer sounds if
the resistance of a circuit under test is <10 Ω , the circuit is in good condition.
• The measured value shows on the display and the unit is Ω .
• When continuity testing has been completed, disconnect the connection between
the test leads and the circuit under test.
Warning: To avoid damage to the meter or to the devices under test, disconnect circuit
power and discharge all the high-voltage capacitors before measuring resistance.
To avoid possible injury, please do not attempt to input voltages higher than 60V DC or
30V AC.

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Diode Test
Perform the diode test to check diodes, transistors, and other semiconductor devices.
The diode test sends a current through the semiconductor junction, and then measures
the voltage drop across the junction. A good silicon junction drops between 0.5V and
0.8V.
To test a diode out of a circuit, connect the meter as follows:
• Insert the red test lead into terminal and the black test lead into the COM terminal.
• Set the rotary switch to to select diode test measurement mode.
• For forward voltage drop readings on any semiconductor component, place the
red test lead on the component’s anode and place the black test lead on the
component’s cathode. The measured value shows on the display.
• Note Connect the test leads to the proper terminals as said above to avoid error
display.
• The LCD will display OL indicating diode being tested is open or polarity is
reversed. The unit of diode is Volt (V), displaying the forward voltage drop
readings.
• Open circuit voltage is around 2.7V.
• When diode testing is completed, disconnect the test leads from the device under
test.
Capacitance Measurement
To measure capacitance, connect the meter as follows:
• Use the multi-purpose socket and connect to the V and mA μA terminals.
• Set the rotary switch to F.
• Connect the test leads across with the object being measured. The measured
value shows on the display.
• When measuring capacitance values larger than 600uF, it is normal for the meter
to require some time to stabilize.
• The LCD displays OL indicating the tested capacitor is shorted or it exceeds the
maximum range.
• When capacitance measurement has been completed, disconnect the test leads
from the device under test.
Note: The Meter displays a xed value which is the value of the meters own internal
circuitry. To ensure accuracy, it is necessary to subtract this value from the displayed
value when measuring small capacitors.
Frequency Measurement
Warning: To avoid the risk of personal injury, do not attempt to measure frequency with
voltage higher than 30V RMS.
To measure frequency, connect the meter as follows:
• Insert the red test lead into the Hz terminal and the black test lead into the COM
terminal.
• Set the rotary switch to Hz to select Frequency measurement mode.
• Connect the test leads across with the object being measured. The measured
value shows on the display.
• When frequency measurement is complete, disconnect the test leads from the
circuit under test.

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Temperature Measurement
To measure temperature, connect the meter as follows:
• Set the rotary switch to ºC to measure degree celsius temperature.
• Insert the multi-purpose socket into the corresponding Hz and COM terminal.
• Insert the temperature probe to the corresponding input terminal of the multi-
purpose socket. Take care to ensure that proper polarity is observed when
connecting to this socket.
• Place the temperature probe to the object being measured. The measured value
shows on the display after few seconds.
• The included point contact temperature probe can only be used under 230ºC.
• For any measurement higher than that, the rod type temperature probe must be
used instead.
• When temperature measurement has been completed, disconnect the connection
between the temperature probe, multi-purpose socket and the circuit under test
and remove the multi-purpose socket from the input terminal.
Note
The testing environment must between 18ºC to 28ºC to ensure accuracy especially
when measuring low temperature. Different reading may be obtained when testing
room environment under short or open circuit situation, then short-circuited reading
shall be considered as the correct reading.
Turning on the Display Backlight
Warning: In order to avoid the hazard arising from mistaken readings in low light
situations, please use display backlight function.
• Press LIGHT button to turn the display backlight on.
• Press LIGHT button again to turn the display backlight off.
• When using the AC power, the display backlight always stays on.
Measuring Transistor
To measure transistor, connect the meter as follows:
• Insert the multi-purpose socket into the μAmA and Hz input terminal.
• Set the rotary switch to hFE.
• Insert the NPN or PNP type transistor to be tested into the corresponding input
terminals of the multipurpose socket.
• The measured nearest transistor value shows on the display.
• When transistor measurement has been completed, remove the tested transistor
from the multi-purpose socket and remove the multi-purpose socket from the input
terminal.

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SPECIFICATION
DC Voltage
Range Resolution Accuracy Overload Protection
200mV 0.1mV
± (0.5%+2) 1000V
Input impedance: ~10M Ω
2V 1mV
20V 10mV
200V 100mV
1000V 1V ± (0.8%+3)
AC Voltage
2V 1mV
± (0.8%+3)
750V
Input impedance: ~10M Ω
Frequency: 45Hz to 400Hz
Display True RMS
20V 10mV
200V 100mV
1000V 1V ± (1.0%+4)
DC Current
200μA 0.1μA
± (0.8%+2) Fuse 500mA, 250V
fast type, f5x20mm
2mA 1μA
20mA 10μA
200mA 0.1mA
10A 10mA ± (2.0%+4) Fuse 10A, 250V
fast type, f5x20mm.
AC Current
2mA 1μA
± (1.0%+3) Fuse 500mA, 250V, fast
type, 5x20mm.
20mA 10μA
200mA 0.1mA
10A 10mA ± (2.5%+5) Fuse 10A, 250V,
fast type, 5x20mm.

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Resistance
Range Resolution Accuracy Overload Protection
200Ω 0.1 Ω
± (0.8%+3) 250V rms
2k Ω 0.001k Ω
20k Ω 0.01k Ω
200k Ω 0.1k Ω
2M Ω 0.001M Ω
20M Ω 0.01M Ω± (1.2%+5)
200M Ω
Capacitance
20nF 10pF
± (4%+3) 250V rms2μF 1nF
200μF 100nF ± (5%+5)
Frequency
2kHz 1Hz
± (1.5%+5) 250V rms
200kHz 100Hz
Temperature
ºC 1ºC
-40ºC to -20ºC
- (8%+5)
250V rms
>20ºC to 0ºC
± (1.2%+4)
>0ºC to 100ºC
± (1.2%+4)
>100ºC to 1000ºC
± (2.5%+10)
Continuity Test
Range Resolution Overload Protection Remarks
1 Ω 250V rms
Open circuit voltage
approximate 3V.
When circuit disconnected
with resistance
value >100 Ω
buzzer does not sound.
When circuit is in good
connection with resistance
value 10 Ω buzzer sounds
continuously
Diode Test
1mV 250V rms Open circuit voltage
approximate 3V.
Transistor
hFE 1ßFuse 500mA, 250V
fast type, 5x20mm
Vce 2.5V, 1bo 10μA
1000ßMAX

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MAINTENANCE
Cleaning
• Periodically wipe the case with damp cloth and mild detergent. Do not use
abrasives or solvents for cleaning.
• Clean the measurement probe tips occasionally, as dirt on the probes can affect
reading accuracy.
Replacing the fuses
• Press the POWER button to turn the meter off, disconnect the power cord and
remove all connections from the terminals.
• Open the accessories compartment at the top of the front cover, then open the
fuse compartment to replace fuses. Remove the fuse by gently prying it loose from
its holder. Install the replacement fuse.
• Use ONLY replacement fuses with the identical type and specication as follows
and make sure the fuse is inserted rmly in the holder.
• Fuse 1: 250mA, 250V, fast type, 5x20mm (AC220V)
• Fuse 2: 10A, 250V, fast type, 5x20 mm (A)
• Fuse 3: 250mA, 250V, auto recovery, 5x20 mm (μA, mA)
• Fuse 4: 500mA, 250V, fast type, 5x20 mm (hFE)
Replacing the Battery
Warning: To avoid false readings, replace the battery as soon as the battery indicator “
” appears when using battery to power on the meter.
• Press the POWER to turn the meter off and remove all connections from the
terminals.
• Open the accessories compartment at the top of the front case.
• Open the battery compartment inside the accessories compartment.
• Remove all the batteries from the battery compartment.
• Replace the battery with new 6pcs of 1.5V battery (R14).
• Ret the battery compartment cover and also the accessories compartment cover.

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INFORMATION ON WASTE DISPOSAL FOR CONSUMERS OF
ELECTRICAL & ELECTRONIC EQUIPMENT
These symbols indicate that separate collection of Waste Electrical and Electronic Equipment
(WEEE) or waste batteries is required. Do not dispose of these items with general household
waste. Separate for the treatment, recovery and recycling of the materials used. Waste batteries
can be returned to any waste battery recycling point which are provided by most battery retailers.
Contact your local authority for details of the battery and WEEE recycling schemes available in
your area.
Made in China. PR2 9PP
Man Rev 1.0