Tenma 72-9390 User Manual

72-9390 Pen Type Meter

r

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.

The Tenma 72-9390 (hereafter referred to as
“the Meter”) are 3000 counts pen type digits
millimeters. The Meter uses large scale of
integrated circuit with professional multimeter
IC as its core and has full range overload
protection.

The Meter measures or tests the following:

AC/DC voltage
Resistance
Diode
Continuity
Capacitance

Unpacking Inspection

Open the package case and remove the
Meter. Check the following items carefully to
see any missing or damaged part:

Item Description

1

2 Test Lead 1 pai
In the event you find any missing parts or
damage, please contact your dealer
immediately.

Safety Information

This Meter complies with standards EN61010:
in pollution degree 2, over voltage category
(CATIII 300V) and double insulation.
CAT.III: Distribution level, fixed installation,
with smaller transient over voltages 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 on.

Instructions for Safe Operation

English Operating
Manual

ty

1 piece

measurements.

Disconnect circuit power and discharge all
high voltage capacitors before testing current,
resistance, diodes or continuity.

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.

The internal circuit of the Meter shall not be
altered at will; doing so will damage the Meter
and may cause personal injury.

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.

Do not use or store the Meter in an
environment of high temperature, humidity,
explosives, flammable mateirals and strong
magnetic field. The performance of the Meter
may deteriorate after dampened.

International Electrical Symbols

Deficiency
of Built-In
Battery
AC
(Alternative
Current)
Double
Insulated

AC or DC Diode

Conforms to Standards of European

Warning. Refer to the Operating
Manual

The Meter Structure (see figure 1)

Figure 1

1. Front Housing

2. Functional buttons

3. Switch

4. LCD Display

5. Input Terminals

Display Symbols (see figure 2)

Grounding

DC (Direct
Current)

Continuity
Test

Press SELECT to switch between resistance,
AC/DC voltage, continuity buzzer and diode
measurement modes. Press and hold to exit
“sleep” mode.

2

HOLD

Press HOLD to enter and exit hold mode
(except under auto scan mode).
Press and hold the HOLD button, the meter
automatically holds the value which obtains at
6 seconds later, at this time,
If the Meter enters “sleep” mode with hold
mode, the meter will still be in the hold mode
when it is turned on.

3

MAX/MIN

The MAX/MIN mode stores minimum (MIN)
and maximum (MAX) input values (except
under auto scan mode). Manual ranging
comes when you select this function.
Press MAX/MIN button MAX
MAX/MIN and vice versa.
Under hold mode and max/min mode, should
exit hold mode first then press and hold
MAX/MIN more than 1 second to exit
max/min mode.

4.

(BACKLIGHT & LED)

Press once to turn the display backlight and
test lead LED on and press again to turn the
display backlight and test lead light off. It will
automatically turn off after a minute.

5. AUTO POWER OFF

To preserve battery life, the Meter
automatically goes into a “sleep” mode if you
do not press any button for around 10 minutes.
The Meter can be activated by pressing any
button, then it returns to the display for the
function selected previously

Measurement Operation

Before measurement, pull down and twist the
red cover counter-clockwise to expose the
input terminal.
When all the measurement has been
completed, twist the red cover clockwise to
protect the input terminal. (see figure 3)

Figure 3

1. AC / DC Voltage Auto Measurement

is displayed.

MIN

than 300V voltage although it is possible to
measure higher voltage.

Set the switch to V

Press SELECT to select DC voltage

measurement mode

Connect the test leads with the object being
measured. The measured value shows on the
display.

When voltage measurement has been
completed, disconnect the connection
between the testing leads and the circuit
under test, and remove the testing leads from
the input terminal of the meter.

3.AC Voltage Measurement

Warning

To avoid damage to the Meter, never input
higher than 300 V.

Set the switch to “V

Press SELECT to select AC voltage
measurement mode

Connect the test leads across with the
object being measured. The measured value
shows on the display.

When voltage measurement has been
completed, disconnect the testing leads from
the circuit under test, and remove the testing
leads from the input terminal of the meter.

Note:

The threshold voltage of AC voltage is around
400mV.

5.

Warning

To avoid damages to the Meter or to the
devices under test, disconnect circuit power
and discharge all the high-voltage capacitors
before measurement.

Set the switch to

Auto measurement mode is the default
which the meter can measure Resistance,

Diode, Continuity and Capacitance
automatically.

·For berst accuracy, remove the component
being measured from the circuit before
measurement.

Auto measurement

”

, in

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. Pay attention to the
insulation around the connectors.

Inspect the test leads for damaged insulation
or exposed metal. Check the test leads for
continuity. Replace damaged test leads with
identical type and electrical specifications
before using the Meter.

When using the test leads, keep your fingers

behind the finger guards.

Do not apply more than the rated voltage, as
marked on the Meter, between the terminals
or between any terminal and grounding.

When the Meter is being used on voltage
over 60V DC or 30V AC, special care should
be taken for there is danger of electric shock.

Use the proper function, and range for your

1 2 3

1. Auto scan mode

2. High voltage indicator

3. Data hold

4. Negative reading

5. Autorange mode

6. AC voltage

7. DC voltage

8. Low battery
Warning: To avoid false readings, which

could lead to possible electric shock or
personal injury, replace the battery as soon as
the battery indicator appears.

9. Minimum reading

10. Maximum reading

11. Capacitance

12 Diode test

13. Continuity buzzer

14. mv/V : Volts

15.

k

Button function and auto power off

1. SELECT

Ohm. (resistance)

: kilohm; M : Megaohm.

Figure 2

Warning

To avoid damage to the Meter, never input
greater than 300V voltage.
To measure Voltage, connect the Meter as
follows:

Set the switch to V

Auto measuremeng mode is the default.
This mode can measure AC voltage and DC
voltage.

Connect the test leads with the object being
measured. The measured value shows on the
display.

When voltage measurement has been
completed, disconnect the connection from
the test leads and the circuit under test, and
remove the testing leads from the input
terminal of the meter.

Note: The threshold voltage of AC voltage
is around 400mV

2.DC Voltage Measurement

Warning

To avoid harm to the Meter, never input higher

4

When voltage measurement has been
completed, disconnect the testing leads from
the circuit under test.

Note:

Under auto measurement mode, when input
Resistance: <15

or >10M
Capacitance: <400pF or >1mF
Will get an irresponsible value.

6.Resistance Measurement

Warning

To avoid damages to the Meter or to the
devices under test, disconnect circuit power
and discharge all the high-voltage capacitors
before measuring resistance.
To measure resistance, do the following:

Set the rotary switch to .
Press SELECT to select measurement

mode

Connect the test leads with the object being

measured.

When resistance measurement has been
completed, disconnect the testing leads from
the circuit under test, and remove the testing
leads from the input terminals of the Meter

7. Continuity Test

Warning

To avoid damages to the Meter or to the
devices under test, disconnect circuit power
and discharge all the high-voltage capacitors
before continuity test.
To measure resistance, do the following:

Set the rotary switch to

Press SELECT to select
mode

Connect the test leads with the object being

measured.

The buzzer sounds continuously if the
resistance of a circuit under test is
indicates the circuit is in good connection.

Note:

When continuity measurement has been
completed, disconnect the testing leads from
the circuit under test, and remove the testing
leads from the input terminals of the Meter

8. Diodes Test

Warning

To avoid damages to the Meter or to the
devices under test, disconnect circuit power
and discharge all the high-voltage capacitors
before measuring diodes.
To measure diode, do the following:

Set the rotary switch to .

Press SELECT to select
measurement mode

For better accuracy, separate the component
being measured from the circuit before
measurement.

When diodes measurement has been
completed, d disconnect the testing leads
from the circuit under test, and remove the
testing leads from the input terminals of the
Meter

9. Capacitance Measurement

Warning

To avoid damage to the Meter or to the
equipment under test, disconnect circuit
power and discharge all high-voltage
capacitors before measuring capacitance.
Use the DC Voltage function to confirm that
the capacitor is discharged.
To measure capacitance, connect the Meter
as follows:

Set the rotary switch to

5 6 7

.

measurement

30 , it

.

Press SELECT to select measurement

mode

For better accuracy, it better separate the
object being measured from the circuit before
measurement.

When diodes measurement has been
completed, disconnect the testing leads from
the circuit under test, and remove the testing
leads from the input terminals of the Meter

General Specifications

Maximum voltage between red Terminals

and Grounding: 300Vrms.

Maximum Display: 3000. Updates 4

times/second

Temperature:

Operating: 0 ~40 (32
Storage: -10 ~50 ( 14

~104 );
~122 ).

Relative Humidity: 75% @ 0 ~30 ;

50% @ 31 ~40

Altitude: Operating: 2000m;

Storage: 10000m.

Battery Type: 3V Li-MnO2 Button cell
Battery Deficiency: Display “

”.
Dimensions(HxWxL): 20.18x26.5x181.5mm
Weight: Approx.90g (battery included).

Accuracy Specifications

Accuracy: ±

a% reading + b digits
guaranteed for 1 year.
Operating temperature
Relative humidity

18 ~ 28 .

<75%.

A. AC Voltage

Range Resolution Accuracy Overload

Protection

3V 0.001V
30V 0.01V

± (1%+4) 300Vrms

300V 0.1V
Remarks: Input Impedance: 10M
Frequency Response: 40Hz ~ 400Hz

B .DC Voltage

Range Resolution Accuracy Overload

Protection

3V 0.001V

30V 0.01V

± (1%+3) 300Vrms

300V 0.1V
Remarks: Input Impedance: 10M

C. Resistance

Range Resolution Accuracy Overload

300 0.1

± (1%+3)

Protection

300Vrms
3k 1
30k 10
300k 100
3M 1k
30M 10k

±
(1.5%+5)

Remarks: Under auto scan mode the max
range is 3M

D. Continuity Measurement

Range Resolution Remark

0.1

Open Circuit Voltage
around -1.2V
Buzzer beeps at
resistance

10 .
Buzzer not sound
when resistance >
70

F. Diodes Measurement

Range Resolution Overload Protection

1mV 300Vrms

Remark: Open Circuit Voltage around 3V,
Displays approximate forward voltage drop.

G. Capacitance

Range

Resoluti

on

3nF 0.001nF

Accuracy

±(3%+5) 300Vrms

Overload

Protection

30nF 0.01nF

300nF 0.1nF

3 F 1nF

30 F 10nF

300 F 100nF ±(5%+5)

3mF reference

Remarks:

1.Under auto scan mode the max range is
300

F

2. There is a residual reading when the circuit
is open. To measure a small value of
capacitance, subtract it to ensure accuracy.
Maintenance (see figure 4)
This section provides basic maintenance
information and battery replacement
instruction.

SC REW

BAT TERY

Figure 4

Warning

Do not attempt to repair or service your Meter
unless you are qualified to do so and have the
relevant calibration, performance test, and
service information. To avoid electrical
shock or damage to the Meter, do not get
water inside the case.

A. General Service

Periodically wipe the case with a damp cloth
and mild detergent. Do not use abrasives or
solvents.

Clean the terminals using a cotton swab with
mild detergent or contact cleaner, as dirt or
moisture in the terminals can affect readings.

Turn the Meter off when it is not use and
take out the battery when not using for a long
time.

Do not store the Meter in a place of
humidity, high temperature, explosive,
inflammable and strong magnetic field.

B. Replacing the Battery

Warning

To avoid false readings, which could lead to
possible electric shock or personal injury,
replace the battery as soon as the battery
indicator appears.
To replace the battery:

1. Turn the Meter off . Disconnect the
connection between the testing leads and the
circuit under test, and remove the testing
leads away from the input terminals of the
Meter.

2. Remove the screw from battery
compartment and separate the battery
compartment from the case bottom.

3. Remove the battery from the battery
compartment.

4. Replace the battery with a new 3V battery

5. Rejoin the case bottom and the battery
compartment, and reinstall the screw

===END===