Duratool D03128 User manual

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CLAMP METER
MODEL: D03128

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CONTENTS
Page Number Details
3 Important Safety Information
3 Features
4 Product Overview
5 Switches, Buttons & Input Jacks
5 LCD
6Specications
6Electrical Specications
9 Operation
9 Switching REL
9 Switching Frequency or Duty Cycle
9 Switching Maximum or Minimum Value
10 Switching Functions
10 Backlight and Clamp Lighting Bulb
10 Auto Power Off
10 Preparing for Measurement
11 Measuring AC Current
11 Measuring DC Current
12 Measuring AC Voltage
12 Measuring DC Voltage
12 Measuring Frequency
13 Measuring Duty Cycle
15 Measuring Resistance
15 Testing Diode
15 Testing Continuity
16 Measuring Capacitance
16 Maintenance

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IMPORTANT SAFETY INFORMATION
Please read these instructions carefully before use and retain for future
reference.
• When using electrical appliances basic safety precautions should always be
followed.
• Use the meter only as specied in this manual, or the protection provided may be
impaired.
• Do not operate the meter or use test leads if they appear damaged, or if the meter
is not operating properly.
• There are no user-serviceable parts in this product. Refer servicing to qualied
personnel.
• Always use the proper terminal, switch position and range for measurements
before connecting the meter to the circuit under test.
• Verify the meter’s operation by measuring a known voltage.
• Do not apply more than the rated voltage as marked on the meter, between the
terminals or between any terminal and earth ground.
• Use caution with voltages above 30V AC RMS or 60V DC. These voltages pose a
shock hazard.
• Do not take voltage measurement if the value between the terminals and earth
ground exceed 600V.
• Disconnect the circuit power and discharge all high voltage capacitors before
testing resistance, continuity, diodes or capacitance.
• Do not use the meter around explosive gas or vapour.
• When using the test leads, keep your ngers behind the nger guards.
• Remove test leads from the meter before opening the meter case or battery door.
• Never operate the meter with the cover removed or the battery door open.
• Use only the test leads supplied or the protection may be impaired.
• Do not connect the meter to any voltage source while the rotary selector is in the
current, resistance, capacitance, diode or continuity range.
• Replace the batteries as soon as the low battery indicator appears on the display.
• Fit a full set of batteries at one time.
• Remove dead batteries from the appliance or if it is not going to be used for a long
time.
• Never mix old and new batteries together, or different types of batteries.
• Never dispose of batteries in a re, or attempt to recharge ordinary batteries.
FEATURES
This meter is a portable, professional measuring instrument with LCD and backlight.
The meter can perform measurements of AC/DC voltage and current, resistance,
frequency, duty cycle, capacitance as well as diode continuity.
The meter is equipped with:
- Auto range.
- Reading hold function.
- Square value measuring function (at AC A and AC V range).
- Maximum value measuring function.
- Minimum value measuring function.
- Ability to measure frequency by clamp.
- Auto power-off function.

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PRODUCT OVERVIEW
Number Component Number Component
1Current Clamp 11 Hz/Duty Cycle Switch Button
(Hz/%)
2Clamp Lighting Bulb 12 Reading Hold/Backlight Button
(HOLD/B.L.)
3Panel 13 Rotary Selector
4Trigger 14 OFF - Power Switch
5Function Switch Button (SEL) 15 “+” Symbol
6MAX/MIN Switch Button (MAX/
MIN)
16 “-” Symbol
7Relative Switch Button (REL) 17 Rear Case
8Liquid Crystal Display (LCD) 18 Fixing Screw of Battery Cover
9COM Jack 19 Battery Cover
10 Input Jack

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AC Alternating current
DC Direct current
Diode test
Continuity buzzer
AUTO Auto range mode
MAX Maximum value being measured
MIN Minimum value being measured
REL DCA zero and relative measure
Auto power off
Battery low
Indicates that the display data is
being held
%Percent (duty cycle)
mV, V Milli-volts, Volts (Voltage)
AAmperes (Current)
nF, Nanofarad, Microfarad
Ω, kΩ,
MΩ
Ohms, Kilo-ohms, Mega-ohms
(Resistance)
Hz, kHz,
MHz
Hertz, Kilo-hertz (Frequency),
Megahertz
SWITCHES, BUTTONS & INPUT JACKS
Button/Switch/Jack Function
HOLD/B.L button Hold the reading or control the backlight.
SEL button For switching among measuring functions.
REL button Relative value measurement.
Hz/% button Switch between ‘frequency’ and ‘duty’ measurement functions
MAX/MIN button Switch between maximum and minimum value measurement
functions.
Rotary selector Select functions and ranges.
OFF position Turn off the power.
INPUT jack For measuring voltage, resistance, frequency, duty cycle,
capacitance, diode and continuity.
COM jack Common input connection for current, voltage, resistance,
frequency, duty, capacitance, diode and continuity
measurement.
Clamp For measuring current.
LCD
.

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SPECIFICATIONS
Calibration is required once a year and is to be carried out at a temperature between
18°C and 28°C (64°F to 82°F) and relative humidity, below 75%.
Auto range
Overrange protection is provided for all ranges
Maximum voltage between
terminals and earth ground
1000V or 750V rms AC
Operating altitude Max. 2000 metres (7000ft)
Display 4000 counts with analogue bar LCD display
Maximum value display 4000 digits
Polarity indication Automatic ‘-’ for negative polarity
Overrange indication ‘0L’ or ‘-0L’
Converter rate 3 times/sec. Bar graph: 30 times/sec
Unit indication Function and unit
Auto power off time 15 minutes
Operating power 1.5V x 3 AAA batteries
Battery low indication on LCD
Temperature factor < 0.1 x Accuracy
Operating temperature 0°C to 40°C (32°F to 104°F)
Storage temperature -10°C to 50°C (10°F to 122°F)
Dimensions 208mm x 78mm x 32mm
Weight Approximate 340g (including batteries)
ELECTRICAL SPECIFICATIONS
Ambient temperature: 23 ± 5°C
Relative humidity: < 75%
AC Current
Range Resolution Accuracy
40A 0.01A ± (2.0% of rdg + 6 digits)
400A 0.1A
• Max input current: 400A AC
• Frequency range: 40 to 400Hz
• Response: average value
• Max input current: 400A DC
DC Current
Range Resolution Accuracy
40A 0.01A ± (2.0% of rdg + 6 digits)
400A 0.1A

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DC Voltage
Range Resolution Accuracy
400mV 0.1mV ± (1.0% of rdg + 2 digits)
4V 0.001V
± (0.7% of rdg + 2 digits)40V 0.01V
400V 0.1V
600V 1V ± (0.8% of rdg + 2 digits)
• Input impedance: 10MΩ.
• Max. input voltage: 1000V DC.
• At small voltage range, unsteady
readings will appear before the test
leads contact the circuit. This is
normal because the meter is highly
sensitive. When the test leads
contact the circuit, the true reading
will be shown.
AC Voltage
Range Resolution Accuracy
4V 0.001V
± (0.8% of rdg + 3 digits)40V 0.01V
400V 0.1V
750V 1V ± (1.0% of rdg + 4 digits)
• Input impedance: 10MΩ.
• Max. input voltage: 750V rms AC.
• Frequency range: 40 to 400Hz.
• Response: Average value.
Frequency by a range (from current clamp)
Range Resolution Accuracy
10Hz 0.01Hz
± (1.5% of rdg + 5
digits)
1kHz 0.001kHz
>1kHz 0.001kHz
• Measurement range: 10 ~ 1kHz.
• Input current range: ≥ 4A rms AC
(higher input current at higher
frequency).
• Max. input current: 400A rms AC.
Frequency by ACV range
Range Resolution Accuracy
10Hz 0.01Hz
± (1.5% of rdg + 5
digits)
1kHz 0.001kHz
10kHz 0.01kHz
>10kHz 0.01kHz Take it only as reference
• Measurement range: 10 ~ 10kHz.
• Input voltage range: ≥ 0.6V rms
AC (higher input voltage at higher
frequency).
• Input impedance: 10MΩ.
• Max. input voltage: 750V rms AC.
Frequency by Hz/Duty Cycle range
Range Resolution Accuracy
9.999Hz 0.001Hz
± (0.5% of rdg + 3
digits)
99.99Hz 0.01Hz
999.9Hz 0.1Hz
9.999KHz 0.001kHz
99.99KHz 0.01kHz
999.9KHz 0.1KHz
9.999MHz 0.001Mhz
• Overload protection: 250V DC or
250V AC rms.
• Input voltage range: 200mV-10V
AC rms.

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Duty Cycle
Range Resolution Accuracy
0.1% - 99% 0.1% ± 3.0%
By A range (from current clamp):
• Frequency response: 10 ~ 1kHz.
• Input current range: ≥ 4A rms AC.
• Max. input current: 400A.
By ACV range:
• Frequency response: 10 ~ 10kHz.
• Input current range: ≥ 1V rms AC.
• Input impedance: 10MΩ.
• Max. input voltage: 750V rms AC.
By Hz/Duty Cycle range:
• Frequency response: 1 ~ 10MHz.
• Input voltage range: ≥ 500mV rms.
• Overload protection: 250V rms AC.
Resistance
Range Resolution Accuracy
400Ω 0.1Ω
± (0.8% of rdg + 3 digits)
4kΩ 0.001kΩ
40kΩ 0.01kΩ
400kΩ 0.1kΩ
4MΩ 0.001MkΩ
40MΩ 0.1MΩ ± (1.2% of rdg + 3 digits)
• Open circuit voltage: 0.4V.
• Overload protection: 250V
DC or rms AC.
Diode
Range Resolution Function
0.001V
Displaying
approximate
forward voltage
of diode
• Forward DC current ~ 1mA.
• Reversed DC voltage ~ 3.3V.
• Overload protection: 250V DC or rms
AC.
Continuity
Range Resolution Function
0.1Ω
Built-in buzzer
will sound if the
resistance is
lower than 40Ω
• Open circuit voltage ~1.2V.
• Overload protection: 250V DC or rms
AC.
Capacitance
Range Resolution Accuracy
400nF 0.1nF
± (4.0% of rdg + 5 digits)
4μF 0.001μF
40μF 0.01μF
400μF 0.1μF
4000μF 1μF
• Overload protection: 250V
DC or rms AC.

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OPERATION
Holding Readings
• Press the “HOLD/B.L” button to hold the readings while taking measurement and
the value on the display will be held.
• Press the “HOLD/B.L” button again to release the reading hold function.
SWITCHING REL
• The “REL” key is the relative value measurement communication transmission
key that acts with trigger. Pressing this key will enter into the relative value
measurement mode.
• The system will save the display value in the memory as the reference value.
When doing the measurement later, the display value will be the difference value
that the entry value deducts from the reference value.
• Pressing the “REL” key will enter into the Manual Measurement mode
automatically.
• In REL measurement status, press the key again and the REL function will be
relocked.
• Press the key in HOLD status and the Hold function will be cancelled.
• The system will save the display value in the memory as the reference value.
• When doing the measurement later, the display value is the difference that the
entry value deducts from the reference value.
• Press the “SELECT” key or use the “MODE” switch to cancel REL measurement
mode, and go back to normal mode (“RELΔ” will disappear in the LCD).
• OL triggering: Under RELΔ mode, “OL” shows when the input value is larger than
the allowed value of the measurement mode.
• Press the key again and the relative measurement function will be cancelled.
• Disable to enter RELΔ mode when “OL” shows.
• No analogue section bar function under RELΔ mode.
SWITCHING FREQUENCY OR DUTY CYCLE
• When working at the voltage or the current ranges, press the “Hz/%” button once
and the frequency of the voltage or current will be measured.
• Press the “Hz/%” button” twice and the meter will be changed in the duty range for
measuring the duty cycle of the voltage or current.
• At the same time, the meter changes into manual mode.
• Press the “Hz/%” button again and the meter will be back to the condition of the
voltage or current measuring.
Note: When working at the maximum or minimum value measuring function, the meter
can’t be changed into frequency or duty cycle measuring mode.
SWITCHING MAXIMUM OR MINIMUM VALUE
• At all ranges the “MAX/MIN” button once and the meter can be set to the
maximum value measuring mode.
• Press the button twice and the meter can be set to the minimum value measuring
mode.
• Press the button three times and the meter will revert back to normal test mode,
while the maximum and minimum value will be recorded by the chip.
• Press and hold the “MAX/MIN” button for more than two seconds and the meter
will go back to normal testing.
• Note: When measuring maximum or minimum value, the meter will be set to

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manual mode automatically.
• When working at frequency or duty measuring function, the meter can’t be
changed into maximum or minimum value measuring mode.
SWITCHING FUNCTIONS
• The “SEL” key is a function selection key that acts with trigger.
• Pressing the key can choose the required measurement mode:
- To choose DC or AC in DC/AC status,
- To choose Diode or Buzzer in Diode/Buzzer status,
- To choose Ohm, Cap, Diode or Buzzer in Ohm/Cap/Diode/Buzzer status.
• Press the “SEL” key, then turn on the power and the ‘auto power-off’ function will
be cancelled.
• The signal “APO” disappears in the LCD and it enters into Sleep status (power-
off).
• Press the key, then power-on will have the ‘auto power-off’ function.
BACKLIGHT AND CLAMP LIGHTING BULB
• Press the “HOLD/B.L” button for two or more seconds to switch on the backlight.
The light will stay on for 15 seconds.
• When the backlight is on, press and hold the “HOLD/B.L” button for two or more
seconds to turn it off.
• At the current range, when the backlight is switched on, the clamp lighting bulb will
be turned on at the same time.
Note: The LED, which requires a larger working current is the main source of the
backlight. Although the meter is equipped with a timer set at about 15 seconds,
(meaning the light will turn off automatically after about 15 seconds), frequent use of
the backlight will shorten the life of the batteries.
• When the battery voltage is ≤3.7V, the symbol “ ” (low battery) will appear on
the LCD. When the backlight is on, even if the battery is ≥3.7V, the “ ” may
appear because of its large working current, which will cause the voltage to drop.
• In this case, you need not replace the batteries yet. Normally, the batteries can last
until the “ ” appears when the backlight is not being used.
Note: The accuracy of the measurement cannot be assured when the “ ” symbol
appears.
AUTO POWER-OFF
• If the mode switch or keys of the meter has no action within 15 minutes, the
system will power off automatically (sleep mode).
• In auto power-off status, press any key and the meter will “auto power-on”
(operation mode).
PREPARING FOR MEASUREMENT
• Switch on the power by turning the rotary selector. If the battery voltage is lower
than 3.7V, the “ ” symbol will appear, meaning the batteries should be replaced.
• The “ ” symbol shows that the input voltage or current should not exceed the
specied value in order to protect the internal circuit from damage.
• Turn the rotary selector to the required function and range to be measured.
• Connect the common test lead rst and then the charged test leads when making
connection. Take away the charged test lead rst when disconnecting.