UNI-T UT71A, UT71C, UT71D, UT71E, UT71B Operating Manual

P/N:110401103779

Model UT71A/B/C/D/E

OPERATING MANUAL

CHAPTER TITLE PAGE

Model UT71A/B/C/D/E: OPERATING MANUAL

1

TABLE OF CONTENTS

1.

2.

5
5
6
7
7
9
10
10
10
10
10
11
11
12
15
21
24
24

Before You Start

Overview
Unpacking Inspection
Safety Information
Rules For Safe Operation
International Electrical Symbols

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

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Model UT71A/B/C/D/E: OPERATING MANUAL

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30
30
30
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35
37
39
41
43
44
45
47
47
47
48
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3.

4.

CHAPTER TITLE PAGE

Analogue Bar Graph
Using MAX MIN

Making Measurements

Introduction
A. Measuring Voltages
B. Measuring Currents
C. Measuring Resistance
D. Testing for Continuity
E. Testing Diodes
F. Measuring Capacitance
G. Measuring Frequency / Duty Cycle
H. Measuring Temperature
I. 4~20mA loop current as % readout
J. Power Measurement

Using Stores, Recall and Send Features

Introduction
Storing and Clearing Readings
Recalling Stored Readings
Using Send

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Model UT71A/B/C/D/E: OPERATING MANUAL

5.

6.

7.

CHAPTER TITLE PAGE

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49
49
52
52
53
54
55
55
56
57
58
59
60
60
61
63
64

Changing the Default Setting

Introduction
Selecting Setup Options

Maintenance

A. General Service
B. Replacing the Fuses
C. Replacing the Battery

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

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66
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67
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CHAPTER TITLE PAGE

E. Resistance
F. Continuity Test
G. Diode Test
H. Capacitance
I. Frequency
J. Temperature Degrees Celsius Fahrenheit
K. 4~20mA loop current
L. Power Measurement

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Model UT71A/B/C/D/E: OPERATING MANUAL

Chapter 1

Before You Start

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.

Digital Multimeter UT71A/B (hereafter referred to as "the Meter") is a 20000 counts and 4 1/2 digits with steady
operations; Digital Multimeter UT71C/D/E (hereafter referred to as "the Meter") is a 40000 counts and 4 3/4 digits
with steady operations, fashionable structure and auto ranging instrument. They all 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 Data Store, Data Recall, AC True RMS, AC+DC,Low Battery Display,
Double Display Backlight, Data Hold, Automatic Power Off and full overload protection.

UT71B/C/D/E has extra Temperature, 4~20mA Loop, Data Store and Data Recall feature; UT71E has extra Power
Measurement feature.

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Model UT71A/B/C/D/E: 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:

Table 1-1. Unpacking Inspection

Item Description Qty

In the event you find any missing or damage, please contact your dealer immediately.

1
2
3

4
5
6
7
8
9

10

English Operating Manual
Test Lead
K-Type (nickel chromium ~ nickel silicon) Point Contact Temperature Probe (It is
only suitable for measuring temperature under 230 oC
Alligator Clip
Test Clip
USB interface cable
CD-ROM (Installation Guide & Computer Interface Software)
Carrying Bag
Power Adaptor (UT71E only)
9V Battery (NEDA 1604, 6F22, 006P)

1 piece
1 pair
1 piece

1 piece
1 pair
1 piece
1 piece
1 piece
1 piece
1 piece

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Model UT71A/B/C/D/E: OPERATING MANUAL

Safety Information

This Meter complies with the standards IEC61010 safety
measurement requirement: in pollution degree 2,
overvoltage category (CAT. III 1000V, CAT.IV 600V)
and double insulation.

CAT. III: Distribution level, fixed installation, with smaller
transient overvoltage than CAT. IV
CAT.IV: Primary supply level, overhead lines, cable
systems etc.

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.

International electrical symbols used on the Meter and
in this Operating Manual are explained on page 9.

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. 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 model
number or electrical specifications before using the
Meter.
Do not apply more than the rated voltage, as marked
on the Meter, between the 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.

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Model UT71A/B/C/D/E: OPERATING MANUAL

l

l
l
l

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l

When the Meter working at an effective voltage over
60V in DC or 30V rms 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.
When using the test leads, keep your fingers behind
the finger guards.
Disconnect circuit power and discharge all high­voltage capacitors before testing resistance,
continuity, diodes.
Before measuring current, check the Meter's fuses
and turn off power to the circuit before connecting
the Meter to the circuit.
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 and
accident.
The Meter is suitable for indoor use.
Turn the Meter off when it is not in use and take out
the battery when not using for a long time.
Constantly check the battery as it may leak when it
has been using for some time, replace the battery
as soon as leaking appears. A leaking battery will
damage the Meter.

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Model UT71A/B/C/D/E: OPERATING MANUAL

International Electrical Symbols

Symbols used on the Meter and in this manual are explained in Table1-2.

Table 1-2. International Electrical Symbols

AC or DC
DC Measurement
AC Measurement
Grounding
Double Insulated
Warning. Refer to the Operating Manual
Deficiency of Built-In Battery
Conforms to Standards of European Union

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Model UT71A/B/C/D/E: OPERATING MANUAL

Chapter 2

Getting Acquainted

Turning the Meter On

To turn the Meter on, turn the rotary switch from OFF
to any switch setting.

Battery Considerations

The Meter uses one 9V Battery (NEDA 1604, 6F22,
006P). The following paragraphs describe several
techniques used to conserve battery power.

Automatic Power Off

The display blanks and the Meter goes into a "sleep"
mode if you have not changed the rotary switch position
or pressed a button for a set period. While in Sleep
mode, pressing the blue button or turning the rotary
switch could turn the Meter on. The Meter then returns
to the display for the function selected with the rotary
switch; all previously activated button features are
discarded.

Automatic Backlight Off

Press LIGHT button to turn the backlight on and press
LIGHT again to turn it off. Press EXIT to exit the feature.

Press LIGHT to select the backlight level (low or high).
In Setup menu (see Chapter 5), you could specify a
time to automatically turn off the backlight (10 seconds,
20 seconds, 30 seconds or OFF). If the period is set
to OFF, the backlight feature is disabled.

The automatic power off is preset to 10 minutes. From
the Setup menu (see Chapter 5), you could specify a
time (10 minutes, 20 minutes, 30 minutes or OFF). If
you set to OFF, the Meter retains on until you turn the
rotary switch to OFF or the battery becomes too weak.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Low Battery Indication

A constant battery icon ( ) in the upper left corner of
the display notifies you that the batteries are low and
should be replaced.

Warning

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

The Meter Structure

The Figure 2-1 shows the Meter structure.

1. LCD Display

2. Functional Buttons

3. Rotary Switch

4. Input Terminals
Figure 2-1. Meter Structure

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Model UT71A/B/C/D/E: OPERATING MANUAL

Rotary Switch

Turn the Meter on by selecting any measurement function. The Meter presents a standard display for that function.
The display may also be influenced by some of the choices made in Setup.

Use the blue button to select any rotary switch alternate function (labeled in blue letters).
When you turn the rotary switch from one function to another, a display for the new function appears. Button choices

made in one function do not carry over into another function.
The Table 2-1 described each rotary switch position

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-1. Rotary Switch Selections

Rotary

Switch Position

Rotary Switch Function Blue Key Function

Turn the Meter off
DC voltage measurement
AC voltage measurement
AC or DC voltage measurement
DC millivoltage measurement

DC millivoltage measurement
Resistance measurement

Power measurement
Capacitance measurement
Centigrade temperature measurement

None
None
None
Toggle between AC or DC voltage measurement
Frequency measurement
Frequency signal duty cycle measurement
None
Diode test
Continuity test
None
None
Fahrenheit temperature measurement

OFF

V

Hz %

mV

ºC ºF

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V

V

l
l

mV

(UT71B/C/D)

W (UT71E only)

(UT71B/C/D )

(UT71A/B/C/D )
(UT71A/B/C/D )

(UT71E only)

(UT71A/E)

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Model UT71A/B/C/D/E: OPERATING MANUAL

Rotary

Switch Position

Rotary Switch Function Blue Key Function

Centigrade temperature measurement

AC or DC current measurement (400µA ,4000µA)
AC or DC current measurement (40mA ,400mA)

AC or DC current measurement (10A)

Fahrenheit temperature measurement

Frequency measurement
Frequency signal duty cycle measurement
Toggle between AC or DC current
Toggle between AC or DC current
4~20mA loop current as % reading
Toggle between AC or DC current

mA

µA

A

(4~20mA)

%

l
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l

(UT71E only)

∫C ∫F

Hz %

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Model UT71A/B/C/D/E: OPERATING MANUAL

Functional Buttons

The buttons activate features that augment the function selected with the rotary switch. The buttons are shown
in Table 2-2.

STORE

RECALL

Press the button once to access the main feature (e.g. STORE).
To access the first additional feature of the button (e.g. RECALL), press and hold the button for over 1 second to

access this additional feature. This additional feature appears right above or on the left hand side of the appropriate
keys.

To access the second additional feature of the button (e.g. ), press once the button again while the Meter has
already entered the first additional feature (e.g. RECALL). The second additional feature appears on the right hand
side above the appropriate keys.

The RANGE and EXIT buttons has only one additional feature.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-2. Functional Buttons

Button Description Access Method

RANGE

SETUP

STORE

RECALL

Press the button once.

Press and hold the button while
turning on the Meter

Press and hold the button for more
than 1 second

Press the button
once.

Range feature:
Exit AUTO and enter MANUAL ranging. In MANUAL, select
next input range. EXIT to return to AUT O. AUTO is default.
Testing resistance signal from calibrator:
When testing resistance signal from calibrator, it is necessary
to press this button to change the maximum display to 4000
counts but the accuracy remains unchanged.
Setup feature:
Access Setup selections, the display shows "SET".
In the Setup mode, each press of SETUP button steps to
the next Selection
Store feature:
Store the current measurement value. Press EXIT to exit
the Store feature.

Model UT71A/B/C/D/E: OPERATING MANUAL

17

Table 2-2. Functional Buttons

Button Description Access Method

Press and hold the button for over 1
second
Press the button
once after entering Setup mode.

Press the button once.

Press and hold the button for over 1
second.

Press the button once after entering
Setup or Recall or Store mode.

Recall feature:
Recall the stored value. Press EXIT to exit the Recall feature.
Setup feature:
In Setup, press to select OFF at the selection of HIGH and
LOW
Hold feature:
Press HOLD to freeze the displayed value. Press EXIT to
release the display.
Peak Hold feature:
Press to access Peak Hold feature, the primary display
shows PEAK HOLD. Press EXIT to exit.
In Setup, each press to select the digit you want to edit.
In Recall, press to enable SEND feature
In Store, press to toggle between clearing all the stored
reading or start storing reading from the current index number.

STORE

RECALL

HOLD

Peak HOLD

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-2. Functional Buttons

Button Description Access Method

Press the button once.

Press and hold the button for over 1

second.

Press the button once.

Press and hold

the button for over 1 second.

Press the button once after entering

SEND mode.

Press to exit certain button functions and the Meter will return

to the factory default setting.

Press to turn the backlight on. It is possible to toggle between

1st and the 2nd backlight level and Exit the feature by pressing

this button. After exiting the light feature, it is necessary to press

and hold the button for over 1 second to turn the backlight on

again.

Press to display max, min and average values.

Press EXIT to stop and return to current measurement mode.

Press to output the data, AUTO mode switch off. The primary

display shows "SEND".

Press EXIT to exit.

In Setup, each press to decrement an Option.

In Recall, each press to go back to the previous stored reading.

EXIT

LIGHT

MAXMIN

SEND

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Model UT71A/B/C/D/E: OPERATING MANUAL

Press the button once.

Press and hold the button for over 1
second.

In Store, each press to decrease a second on the storing
interval.
Press EXIT to exit
Press to enter relative mode, the primary display shows .
The left secondary display shows the present measurement
value. The right secondary display shows the stored value.
The primary display shows the present measurement value
minus the stored value.
Press EXIT to exit relative mode.
In Setup, each press to increment an Option.
In Recall, each press to recall the next stored reading.
In Store, each press to increase a second on the storing interval.

Table 2-2. Functional Buttons

Button Description Access Method

MAXMIN

SEND

REL

19

SEND

Press the button once.Press to output the data, AUTO mode switch off. The
primary display shows "SEND".
Press EXIT to exit.

(UT71A only)

Model UT71A/B/C/D/E: OPERATING MANUAL

Blue Button

Press the button once

Press the button once

AC+DC

When it is at AC measurement mode, press the button to
display AC+DC T rue RMS value in the primary display and the
left secondary display "AC+DC".
Use the blue button to select any rotary switch alternate function
(labeled in blue letters).
Press and hold the Button while turning on the Meter to toggle
to 4000 counts for all functions.
It is faster when the Meter is at 4000 counts measurement
mode.
After the Meter is resuming from Automatic Power Off or turn
on and off again, the Meter will back to normal measurement
mode (40000 counts).

Table 2-2. Functional Buttons

Button Description Access Method

20

SEND

Press the button
once after entering Setup mode.

Setup feature:
In Setup, press to select OFF at the selection of HIGH and LOW

(UT71A only)

Yellow Button

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Model UT71A/B/C/D/E: OPERATING MANUAL

The Meter Functions Vs Displays

Table 2-3 shows the cross reference of function and display:

Table 2-3 Functions Vs Displays

Function Primary Display Right Secondary Display Left Secondary Display

DCV
ACV

DCmV

The tested DC voltage value
The tested AC voltage value

The tested DCmV value
The tested resistance value
The tested resistance value
The tested resistance value
The tested frequency value
The tested capacitance value
The tested ºC value
The tested ºF value
The tested DCµA value

No display
The tested frequency value:

45.00Hz~ 100.0kHz
No display
No display
No display
No display
No display
No display
No display
No display
No display

Full range: 4, 40, 400, 1000
Full range: 4, 40, 400, 1000

Full range 400
Full range: 400, 4, 40, 400, 4, 40
Full range value: 400
Full range 4
Full range: 40, 400, 4, 40, 400, 4, 40, 400
Full range: 40, 400, 4, 40, 400, 4, 40
1000
1832
Full range: 400, 4000

ºC

ºF

Hz

DCµA

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-3 Functions Vs Displays

Function Primary Display Right Secondary Display Left Secondary Display

The tested ACµA value

The tested DCmA value
The tested ACmA value

The tested DC current value
The tested AC current value

The tested power value
Data recalled is on

The tested frequency value:

45.00Hz~10.00kHz
No display
The tested frequency value:

45.00Hz~10.00kHz
No display
The tested frequency value:

45.00Hz~10.00kHz
Apparent power value

Full range: 400, 4000

Full range: 40, 400
Full range: 400, 4000

Full range: 10
Full range: 10

Power factor value

ACµA

DCmA
ACmA

DCA
ACA

W

RCL

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-3 Functions Vs Displays

Function Primary Display Right Secondary Display Left Secondary Display

The recalled value

The present measurement value
minus the stored value

The total number of stored value.

The stored value

Index number:
no.0001~no.0100 (For UT71A/B/C/E)
no.0001~no.9999 (For UT71D)

The present measurement value.

STO

MAX MIN

REL

Chapter 2 Getting Acquainted - Using MAX MIN

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Model UT71A/B/C/D/E: OPERATING MANUAL

Selecting the Range

Press RANGE to select either a fixed range or the
autorange feature.

Autoranging (AUTO lighted in the display) always comes
on initially when you select a new function. In autorange,
the Meter selects the lowest input range possible,
ensuring that the reading appears with the highest
available resolution.

If AUTO is already on, press RANGE to enter MANUAL
ranging in the present range. You can then select the
next manual range each time you press RANGE.
Return to autoranging by press EXIT.

Note that there is no MANUAL ranging on REL feature.

Understanding the Display

Display features are shown in Figure 2-2 and described
in Table 2-4.

Figure 2-2. Display Features

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-4. Display Features

No. Symbol Meaning

1

2
3
4
5

6

MAX

MIN

No

ºC, ºF

SET

Maximum reading displayed.
Minimum reading displayed
The sequence of the reading.
Degrees Celsius (default) or Fahrenheit.
Indicates negative reading
The battery is low.
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.
Setup feature is on.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-4. Display Features

No. Symbol Meaning

7
8

9

TrueRMS

AC+DC

, k , M

Hz, kHz, MHz

mV, V

µA, mA, A

Indicator for True RMS value.
For DCV and DCA functions, reading represents the True RMS total of AC and
DC measurements

: Ohm. The unit of resistance.
k :Kilohm. 1 x 103 or 1000 ohms
M :Megaohm. 1 x 106 or 1,000,000 ohms
Hz : Hertz. The unit of frequency in cycles/second.
kHz: Kilohertz. 1 x 103 or 1000 hertz
MHz: Megahertz, 1 x 106 or 1,000,000 hertz.
V: Volts. The unit of voltage.
mV: Millivolt. 1 x 10

-3

or 0.001 volts
A: Amperes (amps). The unit of current.
mA: Milliamp, 1 x 10-3 or 0.001 amperes.
µA:Microamp.1 x 10

-6

or 0.000001 amperes.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-4. Display Features

No. Symbol Meaning

9

10

11

12

13
14

15

16

nF,µF,

mF

STO
RCL

LOW

HIGH

AUTO

SEND

Farad. The unit of capacitance
nF: Nanofarad. 1 x 10

-9

or 0.000000001 farads.

µF:Microfarad.1 x 10

-6

or 0.000001 farads.
mF: Millifarad. 1 x 10-3 or 0.001 farads.
Automatic power off feature is on
Continuity test
Data store is on
Data recall is on
The relative mode is on to display the present value minus the stored value.
The indicator for the lowest setup limit.
The indicator for the highest setup limit.
The Meter is in the auto range mode in which the Meter automatically selects the
range with the best resolution.
Data output is in progress

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 2-4. Display Features

No. Symbol Meaning

17
18
19
20
21

22
23
24
25
26

HOLD

PEAK HOLD

%

OL

Analogue Bar Graph

Backlight feature is on
Data hold mode is active
Peak hold mode is active
Diode test
Frequency signal duty cycle.
4~20mA loop current as % reading
The input value is too large for the selected range.
Provides an analog indication of the present input, quick response.
Indicator of power factor.
Indicator of apparent power unit.
Indicator of power measurement

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Model UT71A/B/C/D/E: OPERATING MANUAL

Analogue Bar Graph

The bar graph provides an analogue indication of the
measured input. For most measurement functions, the
bar graph updates 10 times per second.

Using MAX MIN

The MAX MIN mode stores minimum (MIN) and
maximum (MAX) input values. When the input goes
below the stored minimum value or above the stored
maximum value, the Meter beeps and stores the new
value.

Press MAX MIN to enter MAX MIN mode. The sampling
time is every 2 seconds. The maximum reading and
MAX are shown on the left secondary display. The
minimum reading and MIN are shown on the right
secondary display. The primary display shows the
current measurement reading.

Press MAX MIN the second time, the current
measurement reading is shown on the left secondary
display. The minimum reading and MIN are shown on

the right secondary display. The primary display shows
the maximum value.

Press MAX MIN the third time, the current measurement
reading is shown on the left secondary display. The
maximum reading and MAX are shown on the right
secondary display. The primary display shows the
minimum value.

Each subsequent press of MAX MIN steps through the
above three modes.

To exit MAX MIN mode, press EXIT.
Press HOLD to stop the Meter updating reading.
MAX MIN mode can only be used under MANUAL

ranging mode.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Chapter 3

Making Measurement

Introduction

Chapter 3 explains how to make measurements. Most
measurement functions can be selected by using the
rotary switch.

While letters or symbols identify primary functions; blue
letters or symbols identify alternative functions. Press
the BLUE button to access these alternate functions.

A. Measuring Voltages

Warning
To avoid harms to you or damages to the Meter
from electric shock, please do not attempt to
measure voltages higher than 1000V, although
readings may be obtained.

To measure voltages, set up the Meter as Figure 3-1
and do the following:

Figure 3-1. Voltages Measurement

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Model UT71A/B/C/D/E: OPERATING MANUAL

Insert the red test lead into the V terminal and the
black test lead into the COM terminal.
Set the rotary switch to or or ;
Set the rotary switch to or or (UT71E).
The default is DC voltage measurement, press BLUE
button to switch to AC voltage measurement mode.
Connect the test leads across with the object being
measured.
The measured value shows on the display.
AC measurement displays the True RMS value.
DC measurement displays the effective value of sine
wave (mean value response).

1.

2.

3.

4.

V

mV

V

When a ACV function is selected, you can press the
Yellow Button to view the AC + DC True RMS value
in the primary display. To exit, please EXIT button.

The BLUE button cycles among , frequency and
duty cycle.

mV

V

mV

V

Note

When measuring voltage, the Meter acts around a
10M ( and ) or 2.5G ( ) impedance in
parallel with the circuit. This loading effect can cause
measurement errors in high impedance circuits. In
most cases, the error is negligible (0.1% or less) if
the circuit impedance is 10k or less.
Special care should be taken when measuring high
voltage.
When voltage measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test and remove testing leads
away from the input terminals of the Meter.

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mV

V

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Model UT71A/B/C/D/E: OPERATING MANUAL

B. Measuring Currents

Warning

If the fuse burns out during measurement, the Meter
may be damaged or the operator himself may be hurt.

To avoid possible damage to the Meter or to the
equipment under test, check the Meter's fuses before
measuring current. Use proper terminals, function,
and range for the measurement. Never place the
testing leads in parallel with any circuit or component
when the leads are plugged into the current terminals.

Figure 3-2. Currents Measurement

To measure AC or DC current, set up the Meter as
Figure 3-2 and proceed as follows:

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Model UT71A/B/C/D/E: OPERATING MANUAL

Turn off power to the circuit. Discharge all high­voltage capacitors.
Insert the red test lead into the mAµA or A terminal
and black test lead into the COM terminal.
If you are using the A terminal, set the rotary switch
to . If you are using mAµA terminal, set the
rotary switch to for currents below 40000µA
(UT71A is 20000µA), or for current above
40000µA (UT71B is 20000µA).
DC measurement is default, press blue button to
select AC measurement.t
Open the circuit path to be tested. Touch the red
testing leads to the more positive side of the break;
touch the black probe to the more negative side of
the bread. Reversing the leads will produce a
negative reading, but will not damage the Meter.
Turn on power to the circuit; then read the display.
AC measurement displays the True RMS value.
DC measurement displays the effective value of sine
wave (mean value response)
Turn off power to the circuit and discharge all high­voltage capacitors. Remove the Meter and restore

1.

2.

3.

4.

5.

6.

7.

A

µA

mA

When a ACA function is selected, you can press the
Yellow Button to view the AC + DC True RMS value
in the primary display. To exit, please EXIT button.

Note

If the value to be measured is unknown, use the
maximum measurement position and reduce the
range step by step until a satisfactory reading is
obtained.
When the measured current is 5A, continuous
measurement is allowed.
When the measured current is between 5A-10A,
continuous measurement 10 seconds and interval
more than 15 minutes.
When current measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test and remove testing leads
away from the input terminals of the Meter.

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Model UT71A/B/C/D/E: OPERATING MANUAL

C. Measuring Resistance

Figure 3-3. Resistance Measurement

Warning

To avoid harms to you, please do not attempt to input
voltage higher than 60V DC or 30V rms AC.

To avoid possible 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, set up the Meter as shown in
Figure 3-3 and follow the following procedure:

Insert the red test lead into the terminal and the

black test lead into the COM terminal.
Set the rotary switch to ; press BLUE button
to select measurement mode.
Connect the test leads across with the object being
measured.

The measured value shows on the display.

1.

2.

3.

The BLUE button cycles among resistance, continuity,
and diode.

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Model UT71A/B/C/D/E: OPERATING MANUAL

D. Testing for Continuity

Warning

To avoid harms to you, please do not attempt to input
voltage higher than 60V DC or 30V rms AC.

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

To test for continuity, set up the Meter as Figure 3-4
and do the following:

Insert the red test lead into the terminal and the
black test lead into the COM terminal.
Set the rotary switch to ; press BLUE button
to select measurement mode and connet the
test leads across with the object being tested.
The beeper comes on continuously for open
conditions, that is test resistance 50 .

1.

2.

3.

The BLUE button cycles among resistance, continuity,
and diode.

Note

When measuring low resistance, the test leads can
add 0.1 to 0.2 of error to resistance measurement.
To test the leads, touch the probe tips together and
read the resistance of the leads. If necessary, you
can press REL to automatically subtract this value.
For high-resistance measurement (>1M ), it is normal
taking several seconds to obtain a stable reading.
In order to obtain precision readings, use the test
lead as short as possible.
The LCD displays OL indicating open-circuit or the
tested resistor value is higher than the maximum
range of the Meter.
When testing the resistance signal from the calibrator,
it is necessary to press and hold the RANGE while
turning on the Meter to change the maximum display
to 4000 counts but the accuracy remains unchanged.
When resistance measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test and remove testing leads
away from the input terminals.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Figure 3-4. Continuity Test

Note

Open circuit voltage around -1.2V and range is 400
measurement range.
When continuity testing has been completed,
disconnect the connection between the testing leads
and the circuit under test and remove the test leads
away from the input terminals.

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Model UT71A/B/C/D/E: OPERATING MANUAL

E. Testing Diodes

Figure 3-5. Diode Test

Warning

To avoid harms to you, please do not attempt to input
voltages higher than 60V DC or 30V rms AC.

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

Use the diode test to check diodes, transistors, and
other semiconductor devices. The diode test sends a
current through the semicondutor junction, then measure
the voltage drop across the junction. A good silicon
junction drops between 0.5V and 0.8V

To test the diode out of a circuit, set up the Meter as
Figure 3-5 and proceed as follows:

Insert the red test lead into the terminal and the
black test lead into the COM terminal.
Set the rotary switch to ; and press BLUE
button to select measurement mode.

1.

2.

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Model UT71A/B/C/D/E: OPERATING MANUAL

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 red test lead polarity
is "+" while the black test lead polarity is "- ".
The measured value shows on the display.

3.

The BLUE button cycles among resistance, continuity,
and diode.

Note

In a circuit, a good diode should still produce a
forward voltage drop reading of 0.5V to 0.8V; however,
the reverse voltage drop reading can vary depending
on the resistance of other pathways between the
probe tips.
Connect the test leads to the proper terminals as
said above to avoid error display.
The LCD will display OL indicating either open circuit
or wrong polarity connection.
The unit of diode is volt (V), displaying the positive­connection voltage-drop value.
Open circuit voltage approximate 2.8V.

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the connection between the testing leads and the
circuit under test and remove the test leads away
from the input terminals.

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Model UT71A/B/C/D/E: OPERATING MANUAL

F. Measuring Capacitance

Figure 3-6. Capacitance Measurement

Warning

To ensure accuracy, the Meter inside is discharged
against the tested capacitor. "DIS.C" will be shown
on the display when it is under discharging, this
process will be quite slow.

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, set up the Meter as shown
in Figure 3-6 and proceed as follows:

Insert the red test lead into the terminal and
the black test lead into the COM terminal.

1.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Set the rotary switch to measurement mode,
the Meter may display a fixed reading which is a
internal distributed capacitor value. For testing less
than 10nF capacitor, the tested value must subtract
the internal distributed capacitor value to maintain
the accuracy.
T o improve the measurement accuracy of small value
capacitors (less than 10nF), press REL with the
test leads open to subtract the residual capacitance
of the Meter and leads.
It is recommended to use test clip to carry out
measurement to reduce the effect of internal
distributed capacitor.

2.

3.

Note

The LCD displays OL indicating the tested capacitor
is shorted or it exceeds the maximum range.
Capacitors larger than 400µF take longer time. The
analogue bar graph shows the time left before
finishing the measurement.

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When capacitance measurement has been
completed, disconnect the connection between the
testing leads and the circuit under test and remove
the test leads away from the input terminals of the
Meter.

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G. Measuring Frequency / Duty Cycle

Figure 3-7. Frequency / Duty Cycle Measurement

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Model UT71A/B/C/D/E: OPERATING MANUAL

Warning

To avoid harms to you, please do not attempt to input
voltage higher than 30V rms.

To measure frequency and duty cycle, connect the
Meter as Figure 3-7 and do the following:

Insert the red test lead into the Hz terminal and
the black test lead into the COM terminal.
Set the rotary switch to (UT71A), (UT71B/C/D)
or (UT71E) and press BLUE button to select
the Hz measurement mode for frequency
measurement or % for duty cycle measurement.
The BLUE button cycles among , frequency
and duty cycle for UT71C and UT71E.
Connect the test leads across with the object being
measured.
The measured value shows on the primary display.

1.

2.

3.

mV

ºC ºF

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Model UT71A/B/C/D/E: OPERATING MANUAL

Note

The requirement of Input amplitude "a" is as follows:
When 10Hz~40MHz: 200 mV a 30Vrms;
> 40MHz: Un-specified
When Hz measurement has been completed,
disconnect the connection between the testing leads
and the circuit under test and remove the test leads
away from the input terminals.

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Model UT71A/B/C/D/E: OPERATING MANUAL

H. Measuring Temperature

Warning
To avoid harms to you, please do not attempt to
input voltages higher than 60V DC or 30V rms AC.

Set the rotary switch to ºC ºF, the display shows OL.
Short circuit the test leads to show the room
temperature. The Meter is default to Celsius ºC
degree unit, you can change units by press the BLUE
button once you have selected the temperature
function.
Insert the point contact temperature probe into the
Meter as figure 10.
Place the temperature probe to the object being
measured.
The measured value shows on the display after
several seconds.

1.

2.

3.

Figure 3-8. Temperature Measurement

ºC ºF

To measure temperature, set up the Meter as shown
in Figure 3-8 and proceed the following.

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Model UT71A/B/C/D/E: OPERATING MANUAL

The rest procedure, please follow B. Measuring
Current: DC current measurement (Figure 3-2).
When the readings obtained is:

2.

3.

Set the rotary switch to , and press BLUE
button to select (4~20mA)% feature.

1.

Note

Place the Meter in an environment of 18ºC~23ºC
otherwise false reading may be obtained especially
in testing low temperature.
The included point contact temperature probe can
only be used with temperature 230ºC below.
When temperature measurement has been
completed, remove the temperature probe away from
the multi-purpose socket, and remove the multi­purpose socket away from the Meter.

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< 4mA, the primary display shows LO
l4mA, the primary display shows 0%. ….
20mA, the primary display shows 100%
> 20mA, the primary display shows HI

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I. 4~20 mA loop current as % readout(UT71B/C/D/E)

It shows the mA measured value or output level in %,
in a 4-20mA scale

To use 4~20mA Loop feature, connect the Meter as
follows:

mA

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Model UT71A/B/C/D/E: OPERATING MANUAL

J. Power Measurement (UT71E only)

Warning

To avoid damages to the Meter, please do not attempt
to input higher than 250V from outlet altogether reading
may be obtained.

Take extra care during measurement to avoid electric
shock.

Switch off the power before the Meter and the object
being measured connect to the circuit.

Set the rotary switch to W.
Insert the power adaptor to the corresponding input
terminals, and plug the power adaptor to the outlet.
Insert the object to be measured into the outlet of
the power adaptor.
The measured value shows on the display. The
primary display shows the power value, the left
secondary display show the power factor value and
right secondary display shows the apparent power
value.

1.

2.

3.

4.

Figure 3-9. Power Measurement

To measure power, proceed the following:

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Model UT71A/B/C/D/E: OPERATING MANUAL

Note

The current of the object being measured must >
10A.

5A continuous measurement is allowed.

5A~10A, only 10 seconds continuous measurement
is allowed and the interval between each
measurement must be greater than 15 minutes.
When power measurement has been completed,
first switch off the power, then disconnect the
connection between the adaptor and the outlet.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Press STORE once, STO and "no.xxxx" appears to
confirm the operation and the left secondary display
shows the current measurement reading. Press
to toggle between clearing the stored readings and
start from the first readings or start from the last stored
reading. Right secondary display shows the original
number of records.
Press STORE the second time, STO appears. The
left secondary display shows the storing time interval
in second, it is preset to zero. To change the interval
in second by pressing + or - button. The interval can

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be as high as 255 seconds or as low as 0 second.
Press and hold STORE to access the quick setting.
Press STORE the third time, STO and no appears.
The left secondary display shows the index number
increase one. The right secondary display shows
the value of the corresponding index number, the
primary display shows the current measurement
reading.
If there is not set time to store the reading, each press
of STORE to store one reading. An index number
increase one.
The maximum number of stored reading is 100 (for
UT71C and UT71E) and 9999 (for UT71D). When
the stored readings memory is full, the Meter will stop
storing data.
To exit, press EXIT.
Automatic power off feature will be disabled after
entering this mode.

Chapter 4

Using Store, Recall & Send Features

Introduction

Chapter 4 shows you how to use stores, recall and
communication features available on the Meter

Storing and Clearing Readings

To store readings, proceed as follows:

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Model UT71A/B/C/D/E: OPERATING MANUAL

Press RECALL to recall the stored value and RCL
appears to confirm the operation.
The left secondary display shows the index number
"no.xxxx".
The primary display shows the corresponding recalled
data.
The right secondary display shows the total number
of the stored data.
Press button to enable the SEND feature to export
the data to the computer via USB. The software
shows the data storing time and also the data value.
After the data transferring is completed, the SEND
feature will be disabled automatically.
Press + or - button to view additional stored reading.
Press and hold RECALL to access quick recalling.
Press EXIT to exit recalling.

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Recalling Stored Readings

Use the following procedure to recall the stored reading:

Using Send

When using a Send feature, please refer to the Installation
Guide of the included CD-ROM.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Chapter 5

Changing the Default Setting

Introduction

The Meter allows you to change the default operating configuration of the Meter by changing setup options made
at the factory.

These settings are stored and can be changed in the Setup mode using the procedure described in this chapter.

Selecting Setup Options

To enter the Setup mode, turn the Meter on and press and hold SETUP button for over 1 second. It is recommended
to change the default setting only when the Meter is at DCV measurement mode.

In the Setup mode, each press of SETUP button steps to the next Selection. Each press of - or + button decrement
or increment an Option.

Each Setup Selection and Option appears in the primary display in the sequence shown in Table 5-1.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 5-1. Setup Selections

Selection Option Factory Default Description

Max. 40000. Press to select OFF
Press to select the digit you want to edit
Max. 40000. Press to select OFF
Press to select the digit you want to edit
10
20
30
OFF
1
OFF
10
20
30
OFF

OFF

OFF

10 mins

1

10

Over the upper limits, beeps not
continuously.
Over the lower limits, beeps not continuously.

10 mins power off
20 mins power off
30 mins power off
Power off feature is disabled
Beeps continuously and icon lights on
No beep, icon flashes
Backlight turn off in 10 seconds
Backlight turn off in 20 seconds
Backlight turn off in 30 seconds
Disable backlight feature.

HIGH

LOW

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Model UT71A/B/C/D/E: OPERATING MANUAL

Table 5-1. Setup Selections

Selection Option Factory Default Description

Zero is in the left hand side.
Zero is in the center

Zero is in the

center

It can only apply to DCV , DCI and °C/°F functions.

Analogue

Bar

Graph

Saving Setup Options

At each setup Option, store your choice and exit setup by press EXIT, advance to the next Option by press +.
To exit the Setup mode without saving the present Option, press Setup.

01234

-4 -2 0 2 4

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Model UT71A/B/C/D/E: OPERATING MANUAL

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.

Periodically wipe the case with a damp cloth and mild detergent. Do not use abrasives or solvents.
To clean the terminals with cotton bar with detergent, as dirt or moisture in the terminals can affect readings.
Turn the Meter to OFF when it is not in use.
Take out the battery when it is not using for a long time.
Do not use or store the Meter in a place of humidity, high temperature, explosive, inflammable and strong magnetic
field.

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Chapter 6

Maintenance

This chapter provides basic maintenance information including battery and fuse replacement instruction.

A. General Service

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Model UT71A/B/C/D/E: OPERATING MANUAL

Warning

To avoid electrical shock or arc blast, or personal
injury or damage to the Meter, use specified fuses
ONLY in accordance with the following procedure.

Turn the rotary switch to OFF and remove all
connections from the terminals.
Remove the 5 screws from the case bottom.
Remove the fuse by gently prying one end loose,
then take out the fuse from its bracket.
Install ONLY replacement fuses with the identical
type and specification as follows and make sure the
fuse is fixed firmly in the bracket.
Fuse 1: 0.5A, 1000V, fast type fuse, 6.3x32mm
Fuse 2: 10A, 1000V, fast type fuse, 10.3x38mm
Rejoin the case bottom and case top, and install the
5 screws.

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B. Replacing the Fuses

Figure 6-1. Fuse Replacement

Follow Figure 6-1 and proceed as follows to replace
the Meter's fuse:

Replacement of the fuses is seldom required. Burning
of a fuse always results from improper operation.

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Model UT71A/B/C/D/E: OPERATING MANUAL

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.

Make sure the test leads are disconnected from the
circuit being tested before opening the case bottom.

Turn the rotary switch to OFF and remove all
connections from the terminals.
Remove the screw from the battery compartment,
and separate the battery compartment from the case
bottom.
Replace with a new 6F22 9V battery.
Rejoin the case bottom and battery compartment,
and reinstall the screw.

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C. Replacing the Battery

Figure 6-2. Battery Replacement

Follow Figure 6-2 and proceed as follows to replace
the battery:

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Model UT71A/B/C/D/E: OPERATING MANUAL

Chapter 7

Specifications

Safety and Compliances

Maximum Voltage between any Terminal and Grounding
Certification
Compliances

Fused Protection for µAmA input terminal:
Fused Protection for A input terminal:

Refer to different range input protection voltage

IEC 61010 CAT.III 1000V, CA T.IV 600V overvoltage and
double insulation standard

0.5A, 1000V, fast type fuse, 6.3x32mm
10A , 1000V,fast type fuse, 10.3x38mm

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Model UT71A/B/C/D/E: OPERATING MANUAL

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Physical Specifications

Display (LCD)

Operating Temperature
Storage Temperature
Relative Humidity

Battery Type
Electromagnetic Compatibility

Dimensions (H x W x L)
Weight

Digital: 40000 counts on primary display; updates 2-3
times / second.
4000 counts on two secondary displays.
Analog: 40 segments; updates 10 times / second.
0ºC~40ºC (32ºF~104ºF)

-10ºC~50ºC (14ºF~122ºF)
75% @ 0ºC~30ºCæ below;
50% @ 30ºC~40ºC:

9V NEDA 1604 or 6F22 or 006P.
In a radio field of 1 V/m below:
Overall Accuracy = Specified Accuracy + 5% of Range
In a radio field of 1 V/m above:
No assigned accuracy is specified.
177 x 85 x 40mm.
Approx.340g (including battery)

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Model UT71A/B/C/D/E: OPERATING MANUAL

General Specifications

Range
Polarity
Overloading

Battery Deficiency

Auto
Auto
Display OL
(except at 4~20mA Loop range which display HI or LO)
Display

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Model UT71A/B/C/D/E: OPERATING MANUAL

Feature Summary

Tri Digital Displays
Analogue Bar Graph

Backlight with 2 brightness levels
Autorange
AC+DC True RMS, AC RMS
Data Hold
Continuity
Bar Graph
Duty Cycle
MAX MIN Mode
Battery Access Door

Primary: 40,000 counts
Left Secondary: 4000 counts
Right Secondary: 4000 counts
Bar Graph: 40 segments, updates 10 times / second
Bright backlight for clear readings in poorly lighted areas.
The Meter automatically selects best range
Choices for AC only or AC+DC readings
Holds readings on display
Beeper sounds for resistance readings below threshold.
40 segments
Measure signal on or off time in %.
Record maximum and minimum
Battery replaceable.

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Model UT71A/B/C/D/E: OPERATING MANUAL

Basic Specifications

DC Voltage
AC Voltage, True RMS
Basic Accuracy

DC Current
AC Current, True RMS
Resistance
Capacitance
Frequency
Temperature
STORE Readings

0 to 1000V
0 to 1000V, 100kHz bandwidth
DC Voltage: 0.025%
AC Voltage: 0.4%
0 to 10A (5~10A for 10 seconds, interval 15 minutes)
0 to 10A (5~10A for 10 seconds, interval 15 minutes)
0 to 40M (UT71A/B is 0 to 20M )
0 to 40mF(UT71A/B is 0 to 20mF)
0~400MHz (UT71A/B is 0 to 200MHz)

-40ºC~1000ºC (-40ºF~1832ºF)(UT71B/C)

Up to 100 readings for UT71C and UT71E or 9999
readings for UT71D may be saved by the user in a
memory. These readings may be viewed by using Recall
feature.

Function Ranges / Description

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Model UT71A/B/C/D/E: OPERATING MANUAL

A. DC Voltage

Range Accuracy Overload

Protection

1000V

Input

Impedance

Around 2.5G

Around 10M

(0.025%+5)

(0.05%+5)

(0.1%+8)

UT71A/B

200mV

2V

20V

200V

1000V

400mV

4V

40V

400V

1000V

UT71C/D/E

Resolution

UT71A UT71C/D/E

(0.1%+8)

(0.15%+8)

(0.05%+5)

(0.08%+5)

(0.1%+8)

UT71B

Detailed Accuracy Specifications

Accuracy: ([% of reading] + [number of least significant digits), guarantee for 1 year.
Operating temperature: 18ºC~28ºC
Relative humidity: 75%RH

0.01mV

0.0001V

0.001V

0.01V

0.1V

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Model UT71A/B/C/D/E: OPERATING MANUAL

Range

Resolution

4V

40V

400V

1000V

Bandwidth

Accuracy

UT71C/D/EUT71C/D/EUT71A/B

2V

20V

200V

1000V

UT71A UT71B

B. AC Voltage (AC+DC measurement is available)

0.0001V

0.001V

0.01V

0.1V

45Hz~1kHz

1kHz~10kHz

10kHz~100kHz

45Hz~1kHz

1kHz~10kHz

10kHz~100kHz

45Hz~1kHz

1kHz~10kHz

10kHz~100kHz

45Hz~1kHz
1kHz~5kHz

5kHz~10kHz

(0.4%+30)

(3%+30)
(6%+30)

(0.4%+30)

(3%+30)
(6%+30)

(0.4%+30)

(5%+30)

Not Specified

(1%+30)
(5%+30)

(10%+30)

(0.8%+40)

(3%+40)
(7%+40)

(0.8%+40)

(3%+40)
(7%+40)

(0.8%+40)

(5%+40)

Not Specified

(1.5%+40)

(0.6%+40)

(3%+40)
(7%+40)

(0.6%+40)

(3%+40)
(7%+40)

(0.6%+40)

(5%+40)

Not Specified

(1.2%+40)

(6%+40)

(10%+40)

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Model UT71A/B/C/D/E: OPERATING MANUAL

Remarks:

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Input Impedance: Approx 10M .
Overload Protection: 1000V.
Display:

a) True rms are valid from 10% of range to 100% of range
b) AC crest factor can be up to 3.0 except 1000V where it is 1.5.
c) A residual reading of 80 digits with test leads shorted, will not affect stated accuracy.
d) When frequency is lower than 100kHz, the accuracy guarantee range 10%-100%.
e) When making AC+DC measurment, the accuray need to add (1%+ 35 digits) of reading based on the above table.

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Model UT71A/B/C/D/E: OPERATING MANUAL

C. DC Current

Range

Resolution

Accuracy

Overload Protection

400µA

4000µA

40mA

400mA

10A

(0.1%+15)

(0.15%+15)

(0.5%+30)

0.5A, 1000V,

fast type fuse,

6.3x32mm

10A, 1000V, fast type fuse,

10.3x38mm

Remarks:

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When the measured current is 5A, continuous measurement is allowed.
When the measured current is between 5A-10A, continuous measurement 10 seconds and interval more than
15 minutes.

At 10A range:

UT71C/D/E UT71C/D/E

200µA

2000µA

20mA

200mA

10A

(0.2%+20)

(0.8%+30)

(0.15%+20)

(0.7%+30)

UT71A/B UT71BUT71A

0.01µA

0.1µA

0.001mA

0.01mA

0.001A

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Model UT71A/B/C/D/E: OPERATING MANUAL

Range

Resolution

400µA

4000µA

40mA

400mA

10A

Bandwidth

Accuracy Overload

Protection

UT71C/D/E UT71C/D/EUT71A/B

200µA

2000µA

20mA

200mA

10A

UT71A UT71B

D. AC Current (AC+DC measurement is available)

0.01µA

0.1µA

0.001mA

0.01mA

0.001A

45Hz~1kHz

1kHz~10kHz

45Hz~1kHz

1kHz~10kHz

(0.7%+15)

(1%+40)

(1.5%+20)

(5%+40)

0.5A, 1000V,

fast type fuse,

6.3x32mm

10A,1000V , fast type

fuse, 10.3x38mm

Remarks:

l

l

Display:
a)True rms are valid from 10% of range to 100% of range

b) AC crest factor can be up to 3.0.
c) A residual reading of 80 digits with test leads shorted, will not affect stated accuracy.
d) When frequency is lower than 100kHz, the accuracy guarantee range 10%-100%.
e) When making AC+DC measurment, the accuray need to add (1%+ 35 digits) of reading based on the above table.

At 10A range:

a) When the measured current is 5A, continuous measurement is allowed.
b) When the measured current is between 5A-10A, continuous measurement 10 seconds and interval more
than 15 minutes.

(1%+15)
(2%+40)

(2%+20)
(6%+40)

(0.8%+15)
(1.5%+40)

(2%+20)
(6%+40)

65

Model UT71A/B/C/D/E: OPERATING MANUAL

Range

Resolution

Accuracy

400

4k

40k

400k

4M

40M

Overload

Protection

UT71C/D/EUT71BUT71AUT71A/B

200

2k

20k

200k

2M

20M

UT71C/D/E

Range Resolution Overload Protection

Remarks:

l
l
l

Open circuit voltage approximate -1.2V.
The buzzer does not sound when the test resistance is > 60 .
The beeper comes on continuously for open conditions, that is test resistance is 40 .

E. Resistance

0.01

0.0001k

0.001k

0.01k

0.0001M

0.001M

(0.3%+8)+test leads

short circuit value

(0.3%+8)

(0.5%+20)

(1%+40)

(1.5%+40)

1000V

F. Continuity Test

0.01 1000V

(0.5%+20)+test leads

short circuit value

(0.5%+20)

(1%+20)
(1%+40)

(1.5%+40)

(0.4%+20)+test leads

short circuit value

(0.4%+20)
(0.8%+20)

(1%+40)

(1.5%+40)

short circuit value

66

Model UT71A/B/C/D/E: OPERATING MANUAL

Range Resolution Overload Protection

Remarks:

l
l

Open circuit voltage approximate 2.8V.
A good silicon junction drops between 0.5V and 0.8V.

H. Capacitance

Range

Resolution

Overload

Protection

40nF

400nF

4µF

40µF

400µF

4mF

40mF

1000V

(1%+20)+

capacitance value of

open circuit test leads

(1%+20)

(1.2%+20)

(5%+20)

Not specified

Accuracy

UT71C/D/EUT71BUT71C/D/EUT71A/B

20nF

200nF

2µF

20µF

200µF

2mF

20mF

(1.5%+20)+

capacitance value of

open circuit test leads

(1.5%+20)

(1.5%+40)

(5%+40)

Not specified

(1.2%+20)+

capacitance value of

open circuit test leads

(1.2%+20)
(1.2%+40)

(1.5%+40)

(5%+40)

Not specified

UT71A

G. Diode Test

0.0001V 1000V

0.001nF

0.01nF

0.0001µF

0.001µF

0.01µF

0.0001mF

0.001 mF

67

Model UT71A/B/C/D/E: OPERATING MANUAL

Remarks:

l

Input amplitude "a" as follows; (DC electric level is zero)
When 10Hz~40MHz : 200mV a 30Vrms;
When > 40MHz : Not specified

I. Frequency

Range

Resolution

Accuracy

Overload Protection

40Hz

400Hz

4kHz

40kHz

400kHz

4MHz

40MHz

400MHz

1000V

(0.01%+8)

Not Specified

UT71C/D/EUT71A/BUT71C/D/EUT71A/B

20Hz

200Hz

2kHz

20kHz

200kHz

2MHz

20MHz

200MHz

(0.1%+15)

Not Specified

0.001Hz

0.01Hz

0.0001kHz

0.001kHz

0.01kHz

0.0001MHz

0.001MHz

0.01MHz

68

Model UT71A/B/C/D/E: OPERATING MANUAL

J. Temperature (UT71B/C/D/E)

Range Resolution Accuracy Overload Protection

1000V

(3%+30)
(1%+30)

2.5%

0.1ºC

-40ºF~32ºF

32ºF~752ºF

752ºF~1832ºF

(4%+50)

(1.5%+50)

3%

Degrees Celsius

0.1ºF

Remarks:

l

Included is a K-Type (nickel chromium ~ nickel silicon) point contact temperature probe which could only measure
temperature below 230ºC. If you want to measure temperature higher than 230ºC, you must use the rod contact
temperature probe.

-40ºC~40ºC

40ºC~400ºC

400ºC~1000ºC

Range Resolution Accuracy Overload Protection

1000V

Fahrenheit

69

Model UT71A/B/C/D/E: OPERATING MANUAL

K. 4~20 mA loop current (UT71B/C/D/E)

Range Resolution Accuracy Overload Protection

(4~20mA)%

0.5A, 1000V, fast type fuse, 6.3x32mm(1%+50)0.01%

Remarks:





< 4mA, the primary display shows LO

4mA, the primary display shows 0% .... ; 20mA, the primary display shows 100%

> 20mA, the primary display shows HI

** END **

When the readings obtained is:

L. Power Measurement (UT71E only)

Range Resolution Accuracy Current Overload Protection

25 00W

1000V

0 . 1 W

10A, 1000V, fast type fuse,

10.3x38mm

Voltage Overload Protection

POWER

VA POWER

Cos POWER

25 00W

1W

(2%+10)

(1%+10)

(2%+10)

Remarks:





Power factor input range: 0.000~1.000
Voltage input impedance: around 10M

.

Voltage input range: AC50~250V

0 ~ 1 0.001W

70

Model UT71A/B/C/D/E: OPERATING MANUAL

This operating manual is subject to change without notice.

Copyright 2005 Uni-Trend Group Limited.

All rights reserved.