UNI-T UT231 Operating Manual

P/N: 41451518

UT231

Digital Power Clamp

Meter

Operating Manual

Model UT231

OPERATING MANUAL

TABLE OF CONTENTS
TITLE PAGE

Model UT231: OPERATING MANUAL

1

Overview
Unpacking Inspection
Safety Information
Rules For Safe Operation
International Electrical Symbols
The Meter Structure
A. The Meter Front Structure
B. The Meter Back and Bottom Structure
Functional Buttons
Display Symbols
Measurement Operation
A. AC Voltage + Frequency Measurement
B. AC Current + AC Voltage Measurement
C. Active Power + Phase Angle Measurement
D. Apparent Power + Reactive Power Measurement
E. Power Factor + Phase Angle Measurement
F. Active Energy + Time Measurement

G. Temperature

+ Temperature Measurement

True RMS Measurement and Average Value Measurement

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24

2

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Model UT231: OPERATING MANUAL

TABLE OF CONTENTS
TITLE PAGE

Three Phases Four Wires and Three Phases Three Wires
Measurement Method
Specifications
A. General Specifications
B. Environmental Requirements
Accuracy Specifications
A. AC Voltage
B. Frequency
C. AC Current
D. Active Power
E. Apparent Power
F. Reactive Power
G. Power Factor
H. Phase Angle
I. Active Energy
J. Temperature
Maintenance
A. General Service
B. Replacing the Battery

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Model UT231: OPERATING MANUAL

This Operating Manual covers information on safety
and cautions. Please read the relevant information
carefully and observe all the Warnings and Notes
strictly.

To avoid electric shock or personal injury, read the
“Safety Information” and “Rules for Safe Operation”
carefully before using the Meter.

Model UT231 is a digital power clamp meter (hereafter

referred to as “the Meter”) is a handheld intelligent
power meter which has both the features of digital
current meter and also power measurement meter.

The Meter can measure Voltage, Current, Active Power,
Apparent Power, Reactive Power, Power Factor, Phase
Angle, Frequency, Active Energy , Temperature and etc.

Warning

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

Unpacking Inspection

Item

1
2
3
4
5
6
7
8

Description

English Operating Manual
Test Lead
Alligator Clip
Point Contact Temperature Probe
USB Interface Cable
Software
Tool Box

1.5V Battery (LR6)

Qty

1 piece
1 pair
1 pair
1 piece
1 piece
1 piece
1 piece
4 pieces

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

Overview

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Model UT231: OPERATING MANUAL

Safety Information

This Meter complies with the standards IEC61010: in
pollution degree 2, overvoltage category (CAT. III 600V,
CAT IV 300V) and double insulation.

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

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 6.

Rules For Safe Operation

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:

Warning

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. Replace damaged test leads
with identical model number or electrical
specifications before using the Meter.
Do not apply more that the rated voltage, as
marked on the Meter.

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Model UT231: OPERATING MANUAL

When measurement has been completed,
disconnect the connection between the test
leads and the circuit under test, remove the
testing leads away from the input terminals of
the Meter and turn the Meter power off.
Do not carry out the measurement when the
Meter’s back case and / or battery door is opened
to avoid electric shock.
When the Meter working at an effective voltage
over 30V in AC, special care should be taken.
Use the proper terminals and function for your
measurements.
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.
Do not use the Meter if the surface of it is wet
or the user’s hands are wet.
When using the test leads, keep your fingers
behind the finger guards.
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 opening the battery door, must make sure
the Meter is power off.
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.
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 UT231: OPERATING MANUAL

The Meter Structure

A. The Meter Face View (see figure 1)

Figure 1

Brack Red

International Electrical Symbols

AC (Alternating Current)
Grounding
Double Insulated
Warning. Refer to the Operating Manual
Deficiency of Built-In Battery
Danger of High Voltage
Conforms to Standards of European Union

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Model UT231: OPERATING MANUAL

1

2

3
4
5
6
7
8

Transformer Jaw: designed to pick up the AC
and DC current flowing through the conductor.
It could transfer current to voltage. The tested
conductor must vertically go through the Jaw
center.
Hand Guards: to protect user’s hand from
touching the dangerous area.
Power button
Max/ button
MENU button
LOAD button (recall data)
CLEAR button (clear the stored reading)
MIN/ button

9
10
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Temperature negative Input Terminal
Temperature positive Input Terminal
V: Voltage Input Terminal
COM Input Terminal
MAX/MIN button
CAL: calibration button
SAVE button (data store button)
USB button
LIGHT button (auto display backlight button)
HOLD button
LCD Display
Testing Leads (Red and Black)
Temperature Probe

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Model UT231: OPERATING MANUAL

B.The Meter Back and Bottom Structure
(see figure 2)

1 Infrared Interface
2 USB Communication Interface Cable

Figure 2

Functional Buttons

Below table indicated for information about the functional
button operations.

Operation Performed

Press and hold POWER for 1 second to
turn the Meter on.
Press POWER again to turn the Meter off.

Press HOLD to enter the Hold mode in
any mode,

appears and

the Meter
beeps.
Press HOLD again to exit the Hold mode
to return to measurement mode, the
Meter beeps and

disappears.
Press LIGHT to turn the display backlight
on.
The display backlight will be off
automatically after 30 seconds.

Button
POWER

HOLD

LIGHT

MENU

H

Press MENU to display the following
functions in sequence:

H

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Model UT231: OPERATING MANUAL

Operation Performed

AC Voltage (main display) + Frequency
(secondary display)
AC Current (main display) + AC Voltage
(secondary display)
Active power (main display) + Phase
angle (secondary display)
Apparent power (main display) +
Reactive power (secondary display)
Power factor (main display) + Phase
angle (secondary display)
Active Energy (main display) + Time
(secondary display)

Temperature

(main display) +

Temperature

(secondary display)
Press LOAD once, MR icon shown, the
Meter displays the next stored reading,
the left secondary display showing the
index increase one.
Press USB once to turn the USB

Button
MENU

Operation Performed

interface on, USB appears and the Meter
beeps.
Press USB again to turn the USB
interface off, USB disappears and the
Meter beeps.
It is invalid at active energy mode.
Press once to enter LOAD mode, MR
appears and the Meter beeps.
Press again to exit LOAD mode, MR
disappears and the Meter beeps.
Press and hold LOAD for 1 second to
display the stored data quickly.

Button

USB

USB

LOAD

Calibrating data. It is not recommended to
calibrate the meter without authorization.

CAL

SAVE

Press once to store single reading, MEM
appears and the Meter beeps.
Press and hold for over 1 second to
continuous store reading, MEM blinks
and the Meter beeps. The index number

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Model UT231: OPERATING MANUAL

Operation PerformedButton

SAVE

shown on the left secondary display keep
on increasing. Press SAVE again to exit.
The maximum number of data store is 99,
when it achieves 99, the Meter shows FUL.
Press CLEAR to clear the stored reading
in order to store next reading.

CLEAR

At active energy range, press to reset
time the zero, then restart the timing.
At all other ranges, press to clear stored
readings.
Press once at LOAD mode, MR icon
shown, the Meter displays the previous
stored reading, the left secondary
display showing the index decrease
one.

MAX/MIN

Starts recording of maximum and
minimum vales. Press to step through
maximum (high), minimum (low) and
the current AC voltage True RMS value

Operation PerformedButton

MAX/MIN at any mode except at the following ranges:

Power factor (main display) + Phase
angle (secondary display)
Active Energy (main display) + Time
(secondary display)

Temperature

(main display) +

Temperature

(secondary display)