Major tech MT760 User manual

MT760
100A AC/DC TRMS
MINI CLAMP METER
INSTRUCTION MANUAL
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Contents Page no
1. Overview..........................................................................................4
2. Open Case Inspection........................................................................4
3. Safety Precautions.............................................................................4
4. Electrical Symbol...............................................................................5
5. General Standard..............................................................................6
6. Product Panel Figure..........................................................................7
7. LCD Full View Figure..........................................................................8
8. Operation Instructions.......................................................................9
9. AC/DC Current Measurement............................................................10
10. NCV Non-contact Field Measurement.................................................11
11. Other Functions...............................................................................11
12. Technical Index...............................................................................12
13. Maintenance and Repair....................................................................15

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1. Overview
The MT760 is a 2000 count True RMS 100A AC/DC mini digital clamp
meter with a resolution of 1mA. The meter measures 600V AC/DC,
capacitance, resistance measurements, plus a continuity buzzer and diode
test function. The VFC function allows the user to measure stable voltage
in high frequency applications of Variable Frequency Drives. Added
features include Zero/Relative mode for Capacitance Zero, resistance,
DCV, ACV, DCA and ACA offset adjustment and Non-Contact voltage
detection. Housed in a modern double moulded rubber housing.
2. Open case inspection
Open the package and take out the instrument. Please check
whether the following accessories are missing or damaged. If any
item is missing or damaged, please contact your supplier immediately.
1. Instruction manual - 1 copy
2. 1.5V AAA battery - 2 pieces
3. Probe assemblies - 1 pair
3. Safety precautions
This Meter complies with EN 61010-1,61010-2-032,61010-2-033,
Pollution Degree 2, measurement category: (CAT II 600V, CAT III 300V)
and Double Insulation standards.
Conforms to UL STD. 61010-1, 61010-2-032, 61010-2-033 Certified
to CSA STD. C22.2 NO. 61010-1,IEC STD 61010-2-032, 6101 0-2-033
CAT II: Applicable to test and measuring circuits connected directly
to utilization points (socket outlets and similar points) of the low voltage
MAINS installation.
CAT Ill: Applicable to test and measuring circuits connected to the
distribution part of the building's low-voltage MAINS installation,
before use and follow all safety instructions.
1. Use the clamp meter by following operation instructions, otherwise
safety functions of the current clamp meter may fail to protect you.
2. Abide by national safety laws and regulations. When operating in
dangerous and live wire exposed environment, use personal
protection equipment to prevent accidents such as electric shock and
arc discharge.
3. Do not cross any position other than protective barrier of current
clamp meter.
4. Before each use, check whether current clamp meter housing or
output cable insulation cracks or damaged first, also check for poor
connected parts. Especially pay attention to insulating layer around
the clamping mouth.

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4. Specifications
5. Before removing the battery cover, please remove clamp meter
from all energized circuit and disconnect lead wire.
6. Do not use clamp meter in circuit with voltage higher than 600V
working or frequency higher than 400Hz.
7. Measurement category class is CAT II 600V/CAT III 300V, pollution
degree is 2. Do not use it out of scope.
8. Be cautious when in environment with exposed wire. Contact with
wire may result in electric shock.
9. For voltage above 60V DC (direct current), 30V AC (AC effective
value) or 42V AC (peak value), such voltage may cause electric
shock.
10. Probe assemblies used for MAINS measurements CAT II 600V/CAT
III 300V according to IEC 61010-031, If you want to replace the
probe assemblies and they need the same level CAT II 600V/CAT
III 300V or better level. Protection impairment if used in a manner
not specified by the manufacturer.
11. Function switches shall be set at the correct position prior to
measurement. Do no switch ranges while measuring voltage or
current.
4. Electrical symbol
Low battery Warning Buzzing on-off
ACV/DCV Diode Earthing
ACA/DCA Double insulation
Danger! High voltage
Comply with European Union directives
Application around and removal from UNINSULATED
HAZARDOUS LIVE conductors is permitted
This symbol signify the product comply with both USA and
Canada requirement

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5. General standard
1. Maximum faulty operation protection voltage between input terminal
and earthing is 600V.
2. Maximum overload protection for clamp head terminal:100A.
3. Maximum display: 2000 Counts, update 2~3 times per second.
Over range displays "OL".
Diode: approx. 3.2V
Range: automatic (exclusive of electricity gear)
Polarity: automatic
Work temperature: 0°C ~40°C
Relative humidity: 0°C ~30°C :75%,30°C ~40°C :50%
Storage temperature: -10°C~50°C
4. Electromagnetic compatibility:
In 1V/m radio frequency field: overall frequency=designated precision
+5%, radio frequency field above 1V/m has no designated index.
5. Work altitude: 0~2000m
6. Built-in battery: AAA 1.5V x 2 pieces
7. Low battery: LCD displays " “.
8. Dimensions: approx. approx. (175 x 60 x 33.5mm), maximum clamp
head size is 17mm.
9. Weight: approx. 170g (including battery)
6. Product panel figure
1. Clamp head.
2. Protective barrier.
3. Clamp head trigger: pull the trigger to open clamp head.
4. NCV indicator: when the induced AC electric field intensity and
induction distance satisfy designated value, it will send out warning
sound and flashes.
5. Function selection button: rotate this button to switch to corresponding
functions indicated on the panel.
6. HOLD/backlight key: for measuring readings/long press 2s to turn on
or turn off backlight.
7. ZERO key: used for DCA zero, capacitance/voltage measurement
relative value.
8. SELECT key: select function mode, such as ACV/DCV, resistance/ on-
off/diode/capacitance, ACA/DCA, etc. in AC voltage and current gear,
long press this key for more than 2s to enter or exit VFC function.
9. LCD display screen: measurement function, symbol and numerical
value.

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10. Positive terminal input jack: when measure voltage, resistance/on off/
capacitance/diode, red meter pen inserts into this jack.
11. lnput jack at COM terminal: when measure voltage, resistance/on off/
capacitance/diode, black meter pen inserts into this jack.
12. lndication mark for geometric center of the clamp head.
figure 1.

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7. LCD full view figure (Figure 2)
figure 2.
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7.
8.
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11.
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14.
15.
16.
17.
No. Symbols Instructions
True Root Mean Square measurement status prompt
AC/DC voltage measurement prompt
Negative reading
Diode measurement prompt
Circuit on-off measurement prompt
Data hold prompt
Resistance unit: 0, kO, MO
Frequency unit: Hz, kHz, MHz
Voltage unit: mV, V
Current unit: mA, A
Capacitance unit: nF, μF, mF
Non-contact AC voltage induction prompt
Auto range prompt
Zero/relative measurement prompt
Variable frequency voltage/current measurement prompt
Low built-in battery prompt
Auto power-off prompt

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8. Operation instructions
1. AC/DC voltage measurement
• Select AC voltage or DC voltage gear
• Insert red meter test lead into red jack (positive terminal), black
meter test lead into black jack (COM terminal)
• Touch the test piece by red and black meter test lead, for
example, power socket (Figure 3).
• Read measurement value from LCD screen .
When measure voltage, maximum input voltage is 600V (AC/DC),
do not exceed this limitation, otherwise it may cause electric shock
or damage to the meter.
2. Resistance/circuit on-off/diode/capacitance
• Insert red meter test lead into red jack (positive terminal), black
meter test leads into black jack (COM terminal)
• Connect meter pen in parallel to test piece for measurement
(Figure 4)
• Read measurement value from LCD screen.
When measure resistance/on-off/capacitance/diode range, do
not input voltage over DC 60V or AC 30V to avoid damage.
figure 3.
figure 4.

9. AC/DC current measurement (Figure 5, Figure 6)
1. AC
• Select AC range (2A ~, 20A ~, 100A ~)
• Open clamp head, hook electric wire (single wire), place electric wire
on geometric center indicated by clamp head, make sure the left
and right clamp heads are totally closed. There is no gap between
the left and right clamp heads.
• Read measurement data from LCD.
2. DC
• Press SELECT key to enter DC range (2A=, 20A:, 100A:)
• Press ZERO key before measurement to make readings zero. If it
does not return to zero after one press, then press it several times
until the reading is zero. Note: as the product is highly sensitive, to
ensure correct measurement data, direction of meter during
measurement should be the same as when it is in zero as much as
possible.
• Open clamp head, hook electric wire (single wire), place electric wire
on geometric center indicated by clamp head, make sure the left
and right clamp heads are totally closed. There is no gap between
the left and right clamp heads.
• Read measurement data from LCD. When the reading is positive, it
means current flows from positive end indicated by clamp head to
the negative end. Negative reading is the opposite .
When measure current, unplug test lead to avoid electric shock.
figure 5.
X
X
figure 6.
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10. NCV non-contact electric field measurement (Figure 7)
If you want to measure whether there is AC voltage or
electromagnetic field, place front end of clamp head 8~15mm
close to the test piece, analog quantity of inductive AC voltage
is about ≤ critical voltage 100V, display "EF", < critical voltage
100V, display"-", it has four"----" levels based on voltage size
with different buzzing at each level, with NCV light flashing to
discriminate electric field intensity .
When ranges switch NCV measurement, please unplug the test
lead to avoid electric shock.
11. Other functions
• HOLD key for 2s to turn on or turn off LCD backlight function.
• Automatic power-off: when measuring, if the rotary button has not
been moved for 15 minutes, the instrument will automatically power
off to save energy. In automatic power-off mode, turn rotary button
to OFF and restart the machine, or click any key to wake the
instrument.
• Turn off automatic power-off function: press and hold SELECT key,
then power-on start, you will hear 5 buzzing which means automatic
power-off function is cancelled. Turn off and restart the machine,
automatic power-off function will be recovered.
• The buzzer will send out 5 warnings 1 minute before automatic
power-off. A long buzz will be heard before power off. When
automatic power-off function is canceled, you will hear 5 continuous
warnings every 15 minutes.
• Buzzer: press any key or rotate function switch, if such function key is
valid, buzzer will "beep" once (lasting approx. 0.25s). In gear, when
figure 7.
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the circuit-under-test is conductive (≤10Ω), buzzer makes sound
continuously. When measure voltage or current outrange, buzzer will
"Beep" to warn outrange, function status is as below:
a) When AC, DC voltage <600V, buzzer beeps
b) 100A AC and DC gear: current >maximum range, buzzer beeps.
• Low-voltage detect: when battery voltage is lower than 2.5V, battery
under-voltage symbol if appears, measurement accuracy may be
lower once this symbol shows, replace battery timely; if it is lower
than 2.2V, only battery under-voltage symbol shows after starting up,
it can't work.
• When battery supply voltage lowers to 2.6V, LCD backlight will be in
weak or non-start state; but measurement functions still work.
12. Technical index
Accuracy: ±(a% reading+ b word count), warranty period is 1 year.
Environment temperature: 23°C ±5°C (73.4°F ±9°F) relative humidity
≤ 75%
Input resistance is about 10MΩ. (as input resistance is high, when
200mV range open circuit, there may be instable digital display,
but measurement can be stabilized once the measured source with
internal resistance lower than 10MΩ is connected, but the impact
of internal resistance of measured source on measurement reading
should be considered)
Maximum input voltage: ±600V
Resolution
200.0mV 0.1mV ±(0.7%+5)
2.000V 1mV
20.00V 10mV ±(0.7%+3)
200.0V 100mV
600V 1V
Range
1. DC Voltage Measurements
Accuracy
Resolution
2.000V 1mV ± (1.0%+3)
20.00V 10mV
200.0V 100mV ±(1.0%+3) V.F.C. mode:± (4.0%+3)
600V 1V ±(1.2%+3) V.F.C. mode:± (4.0%+3)
Range
2. AC voltage measurement
Accuracy
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Input resistance: 10MΩ in average.
Maximum input voltage: 600V RMS
• Show true virtual value. Frequency response: 45~400Hz
• Accuracy guarantee range: 5-100% range, short circuit allows <10
residue readings.
• Non-sinusoidal wave counts add error by crest factor:
When crest factor is 1~2: Add 3%.
When crest factor is 2~2.5: Add 5%.
When crest factor is 2.5-3: Add 7%.
Resolution
200.00Ω* 0.1Ω
2.000kΩ 1Ω ± (1.0%+2)
20.00kΩ 10Ω
200.0kΩ 100Ω
2.000MΩ 1kΩ ± (1.2%+3)
20.00MΩ 10kΩ
Range
3. Resistance measurement
Accuracy
Range: measured value=measurement display value-meter pen
short circuit value - Open-circuit voltage is about 1V
Overload protection: 600V-RMS
Resolution
Resistance value for circuit disconnect:>
150Ω, buzzer makes no sound; Resistance
value for circuit conduct: <1Ω on, buzzer
beeps continuously.
Open circuit voltage is 3.2V: normal voltage
1mV for silicon PN junction is 0.5~0.8V.
Range
4. circuit on-off, diode measurement
Accuracy
0.1Ω
Overload protection: 600V-RMS
Resolution
2nF 1pF ± (4%+10)
20.00nF~200.0μF 10pF~100nF ± (4%+5)
2.000mF~20.00mF 1μF~10μF ±10%
Range
5. Capacitance measurement
Accuracy
Overload protection: 600V-RMS. ≤1μF measured capacitance, it is
suggested to use ZERO measurement mode to ensure accuracy. 13

Resolution
2.000A 1mA ± (2%+8)
20.00A 10mA ± (2%+3)
100.0A 100mA ± (2%+3)
Range
6. DCA measurement
Accuracy
Overload protection 100A
As external electromagnetic field such as the earth exists, to ensure
accuracy of measurement reading, press ZERO key before
measurement to make readings be zero. If it is not zero after one
press, press it for several times until reading is zero. Direction of
meter during measurement should be the same as when it is in zero
as much as possible.
Resolution
2.000A 1mA ±(3%+10) V.F.C mode: ± (4.0%+10)
20.00A 10mA ±(2. 5%+8) V.F.C mode: ± (4.0%+10)
100.0A 100mA ±(2.5%+5) V.F.C mode: ± (4.0%+10)
Range
7 .ACA measurement
Accuracy
Overload protection 100A
• Accuracy warranty coverage: 5~100% range, 2A open circuit
allows <20 residue readings.
• Displays are true valid value. Frequency response: 50~60Hz.
• Non-sinusoidal wave counts add error by crest factor:
a) When crest factor is 1~2: Add 3%.
b) When crest factor is 2~2.5: Add 5%.
c) When crest factor is 2.5~3: Add 7%.
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13. Maintenance and repair
Warning: before removing rear cover of the instrument, make
sure power supply is off; meter leads are removed and
circuit-under-test.
1. General maintenance and repair
Ÿ For maintenance and repair, use wet cloth and mild cleaner to clean
instrument cover, do not use grinding agent or solvent.
Ÿ If the instrument is abnormal, stop use it and maintain.
Ÿ If it is necessary to verify or maintain the instrument, maintain it by
qualified professional serviceman or designated maintenance
department.
2. Replace battery (see Figure 8)
Ÿ When LCD displays under-voltage a prompt, replace built-in battery
immediately otherwise it will affect measurement accuracy.
Ÿ Battery specification: AM 1.5V x 2cells
Operation procedure:
1. Place power switch on "off' position and remove meter pen from input
jack.
2. Unscrew the screw fixed on the rear cover of battery by screwdriver,
remove battery rear cover and take out old battery as shown in the
figure.
3. Replace 2 pcs of new batteries (specification AM1 .5V)
This instruction manual is subject to change without further notice.
figure 8.
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MAJOR TECH (PTY) LTD
South Africa Australia