Tenma 72-8720 User manual

Model 72-8720
OPERATING MANUAL
Model 72-8720: OPERATING MANUAL

Chapter Title Page
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Table of Contents
Model 72-8720: OPERATING MANUAL
1. Before You Start
Overview
Unpacking Inspection
Safety Information
Rules For Safe Operation
International Electrical Symbols
2. Getting Acquainted
Turning the Meter On
Battery Considerations
Automatic Power Off
Automatic Backlight Off
Low Battery Indication
The Meter Structure
Rotary Switch
Functional Buttons
The Meter Functions Vs Displays
Selecting the Range
Understanding the Display
Analogue Bar Graph
Using MAX MIN
3. Making Measurements
A.Measuring DC Voltage
B.Measuring AC Voltage

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Table of Contents
Model 72-8720: OPERATING MANUAL
C.Measuring DC Millivoltage
D.Measuring Currents
E.Measuring Resistance
F.Testing for Continuity
G.Testing Diodes
H.Measuring Capacitance
I. Measuring Frequency / Duty Cycle
J.Measuring Temperature
K.4~20mA loop current as % readout
4. Using Stores, Recall and Send Features
Introduction
Storing and Clearing Readings
Recalling Stored Readings
Using Send
5. Changing the Default Setting
Introduction
Selecting Setup Options
Saving Setup Options
6. Maintenance
A.General Service
B.Replacing the Fuses
C.Replacing the Battery

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Chapter Title Page
Table of Contents
Diode Test
Capacitance
Model 72-8720: OPERATING MANUAL
7. Specifications
Safety and Compliances
Physical Specifications
General Specifications
Feature Summary
Basic Specifications
Detailed Accuracy Specifications
A. DC Voltage
B. AC Voltage
C. DC Current
D. AC Current
E. Resistance
F. Continuity Test
G.
H.
I. Frequency
J. Duty Cycle
K. Temperature
1-1. Degrees Celsius
1-2. Fahrenheit
L. 4~20mA loop current

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Table Title Page
List of Tables
Model 72-8720: OPERATING MANUAL
1-1 Unpacking Inspection
1-2 International Electrical Symbols
2-1 Rotary Switch Selections
2-2 Functional Buttons
2-3 Functions Vs Displays
2-4 Display Features
5-1 Setup Selections

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Table Title Page
List of Tables
Model 72-8720: OPERATING MANUAL
2-1 Meter Structure
2-2 Display Features
3-1 DC Voltage Measurement
3-2 AC Voltage Measurement
3-3 DC Millivoltage Measurement
3-4 DCµA Currents Measurement
3-5 ACµA Currents Measurement
3-6 DCmA Currents Measurement
3-7 ACmA Currents Measurement
3-8 DCA Currents Measurement
3-9 ACA Currents Measurement
3-10 Resistance Measurement
3-11 Continuity Test
3-12 Diode Test
3-13 Capacitance Measurement
3-14 Frequency / Duty Cycle Measurement
3-15 Temperature Measurement
3-16 4~20mA loop current as % readout
6-1 Fuse Replacement
6-2 Battery Replacement

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Model 72-8720: OPERATING MANUAL
Overview
This Operating Manual covers information on safety
and cautions. Please read the relevant information
carefully and observe all the Warnings and Notes
strictly.
Warning
To avoid electric shock or personal injury, read the
Safety Information and Rules for Safe Operation
carefully before using the Meter.
Bench Type Digital Multimeter 72-8720 (hereafter
referred to as the Meter) is a 40000 counts and 4 3/4
digits with steady operations, fashionable structure and
auto ranging instrument. It not only can measure AC
voltage and current, DC voltage and current, Resistance,
Capacitance, Temperature, Frequency, Diodes,
Continuity, 4~20mA Loop, Max/Min, Relative Mode but
also has Setup, Data Store, Data Recall, AC True RMS
or AC+DC Voltage and Current, Low Battery Display,
Chapter 1
Before You Start
White Colour Display Backlight, Data Hold, Automatic
Power Off and full overload protection.

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Item Description Qty
Model 72-8720: OPERATING MANUAL
Unpacking Inspection
Open the package case and take out the Meter. Check the items shown on Table 1-1 carefully to see any missing
or damaged part:
In the event you find any missing or damaged parts, please contact your dealer immediately.
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English Operating Manual
Test Lead
K-Type (nickel chromium ~ nickel silicon) Point Contact Temperature Probe (It is
only suitable for measuring temperature under 230oC
Alligator Clip
Test Clip
USB interface cable
RS232C interface cable
CD-ROM (Installation Guide & Computer Interface Software)
1.5V Battery (R14)
AC220V/50Hz Power Cable
1 piece
1 pair
1 piece
1 piece
1 pair
1 piece
1 piece
1 piece
6 pieces
1 piece
Table 1-1. Unpacking Inspection

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Model 72-8720: OPERATING MANUAL
Safety Information
This Meter complies with the standards IEC61010 safety
measurement requirement: in pollution degree 2,
overvoltage category (CAT. I 1000V, CAT.II 600V) and
double insulation.
CAT. I: Signal level, special equipment or parts of
equipment, telecommunication, electronic, etc., with
smaller transient overvoltage's than overvoltage's CAT.
II.
CAT. II: Local level, appliance, PORTABLE EQUIPMENT
etc., with smaller transient voltage overvoltage's than
CAT. III
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 may 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.
Rules For Safe Operation
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:
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.
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.
Do not apply more than the rated voltage or
current, as marked on the Meter , between the
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International electrical symbols used on the Meter and
in this Operating Manual are explained on page 8.

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Model 72-8720: OPERATING MANUAL
terminals or between any terminal and grounding.
The rotary switch should be placed in the right
position and no any changeover of range shall
be made during measurement is conducted to
prevent damage of the Meter. Must disconnect
the connection between the test leads and the
tested circuit before changing the measurement
position of the rotary switch.
During measurement, do not contact naked wire,
connector, un-used input terminal or the circuit
in used.
When the Meter working at an effective voltage
over 60V in DC or 30V in AC, special care should
be taken for there is danger of electric shock.
Use the proper terminals, function, and range for
your measurements.
If the value to be measured is unknown, use the
maximum measurement position.
Do not use or store the Meter in an environment
of high temperature, humidity , explosive,
inflammable and strong magnetic field. The
performance of the Meter may deteriorate after
dampened.
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When using the test leads, keep your fingers
behind the finger guards.
Disconnect circuit power and discharge all high-
voltage capacitors before testing resistance,
continuity and diodes.
Before measuring current, check the Meterís fuses
and turn off power to the circuit before connecting
the Meter to the circuit.
When under battery operated situation, 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.
When servicing the Meter , use only the same
model number or identical electrical specifications
replacement parts.
The internal circuit of the Meter shall not be altered
at will to avoid damage of the Meter and any
accident.
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
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