Tenma 72-7720 User manual

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Model 72-7720/72-7725: OPERATING MANUAL
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Table of Contents
Title
Overview
Unpacking Inspection
Safety Information
Rules For Safe Operation
International Electrical Symbols
The Multimeter Structure
Functional Buttons
Display Symbols
Measurement Operation
A. DC Voltage Measurement
B. AC Voltage Measurement
C. DC Current Measurement
D. AC Current Measurement
E. Measuring Resistance
F. Model 72-7725:
Frequency Measurement
G. Model 72-7725:
Temperature Measurement
H. Capacitance Measurement
I. Measuring Diodes & Continuity
General Specifications
Testing for Continuity
Sleep Mode
Turning on the Auto Display Backlight
Accuracy Specifications
A. DC Voltage
B. AC Voltage
C. DC Current
D. AC Current

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I. Diodes and Continuity Test 30
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C. Replacing the Fuses
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Model 72-7720/72-7725: OPERATING MANUAL
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Title
E. Resistance Test
F. Model 72-7725: Frequency
G. Model 72-7725:
Temperature
H. Capacitance
Maintenance
A. General Service
B. Replacing the Battery

Overview
Warning
To avoid electric shock or personal injury, read the
"Safety Information" and "Rules for Safe Operation"
carefully before using the Meter.
Digital Multimeters Model 72-720 and 72-7725 (hereafter
referred to as “the Meter”) are 3 1/2 digits with steady
operations, fashionable structure and highly reliable
hand-held measuring instrument. The Meter uses large
scale of integrated circuit with double integrated A/D
converter as its core and has full range overload
protection. The Meter not only can measure AC/DC
Voltage, AC/DC Current, Resistance, Capacitance,
Temperature, Frequency, Diodes and Continuity, but also
has Data Hold, Full Icon Display and Sleep Mode features.
The Meter adopted advanced “co-injection” technique in
order to provide sufficient insulation and anti-shaking.
In addition, the Automatic Display Backlight feature
enables user to work in a dim condition.
Model 72-7720/72-7725: OPERATING MANUAL
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Unpacking Inspection
Open the package case and take out the Meter. Check
the following items carefully for missing or damaged
parts:
In the event you find items missing or damaged, please
contact your dealer immediately.
Model 72-7720/72-7725: OPERATING MANUAL
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Item
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Description
English Operating Manual
Test Lead
Test Clip
Point Contact Temperature Probe
(72-7725 only)
Qty
1 piece
1 pair
1 pair
1 piece

Safety Information
This Meter complies with the standards IEC61010: in
pollution degree 2, overvoltage category (CAT. II 1000V,
CAT. III 600V) and double insulation.
CAT. II: Local level, appliance, PORTABLE EQUIPMENT
etc., with smaller transient voltage overvoltages than
CAT. III
CAT. III: Distribution level, fixed installation, with smaller
transient overvoltages than CAT. IV
Use the Meter only as specified in this operating manual,
otherwise the protection provided by the Meter may be
impaired.
In this manual, a Warning identifies conditions and
actions that pose hazards to the user, or may damage
the Meter or the equipment under test.
A Note identifies the information that user should pay
attention to.
International electrical symbols used on the Meter and
in this Operating Manual are explained on page 8.
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Model 72-7720/72-7725: OPERATING MANUAL

Rules For Safe Operation (1)
Warning
To avoid possible electric shock or personal injury,
and to avoid possible damage to the Meter or to the
equipment under test, adhere to the following rules:
l Before using the Meter inspect the case. Do
not use the Meter if it is damaged or the case
(or part of the case) is removed. Look for cracks
or missing plastic. Pay attention to the insulation
around the connectors.
l Inspect the test leads for damaged insulation
or exposed metal. Check the test leads for
continuity. Replace damaged test leads with
identical model number or electrical specifications
before using the Meter.
l Do not apply more than the rated voltage, as
marked on the Meter, between the terminals or
between any terminal and ground.
l The rotary switch should be placed in the correct
position and no changeover of range shall be
made during measurement, to prevent damage
of the Meter.
l When working at an effective voltage over 60V
DC or 30V rms AC, special care should be taken
for there is danger of electric shock.
l Use the proper terminals, function, and range
for your measurements.
l Do not use or store the Meter in an environment
of high temperature, humidity, explosive,
flammable and strong magnetic field. The
performance of the Meter may deteriorate after
dampened.
l When using the test leads, keep your fingers
behind the finger guards.
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Model 72-7720/72-7725: OPERATING MANUAL

Rules For Safe Operation (2)
l Disconnect circuit power and discharge all high-
voltage capacitors before testing resistance,
continuity, diodes, capacitance or current.
l Before measuring current, check the Meter’s
fuses and turn off power to the circuit before
connecting the Meter .
l Replace the battery as soon as the battery
indicator appears. With a low battery, the Meter
might produce false readings that can lead to
electric shock and personal injury.
l Remove test leads, test clips and temperature
probe from the Meter and turn the Meter power
off before opening the Meter case.
l When servicing the Meter, use only the same
model number or identical electrical specifications
replacement parts.
l The internal circuit of the Meter shall not be
altered at will to avoid damage of the Meter and
any accident.
l Soft cloth and mild detergent should be used
to clean the surface of the Meter when servicing.
No abrasive and solvent should be used to
prevent the surface of the Meter from corrosion,
damage and accident.
l The Meter is suitable only for indoor use.
l Turn the Meter power off when it is not in use
and take out the battery when not using for a
long time.
l Periodically check the battery as it may leak
after some time.If leakage is apparent,the battery
should be immediately replaced to prevent
damage.
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Model 72-7720/72-7725: OPERATING MANUAL

International Electrical Symbols
AC (Alternating Current).
DC (Direct Current).
AC or DC.
Grounding.
Double Insulated.
Deficiency of Built-In Battery.
Continuity Test.
Diode.
Capacitance Test.
Fuse.
Warning. Refer to the Operating Manual.
Conforms to Standards of European Union.
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Model 72-7720/72-7725: OPERATING MANUAL