Major tech MT775 User manual

MT775
AC/DC TRMS
CLAMP METER
INSTRUCTION MANUAL
II

2

Contents Page no
3
1. Safety ..................................................................................... 4
2. Description ............................................................................ 5
2.1. Meter Description .............................................................. 5
10. Temperature Probe Replacement ..................................... 14
4.3. Resistance Measurement ............................................... 11
5.4. REL/Backlight Button....................................................... 14
3.2. General Specifications ...................................................... 9
4.4. Diode and Continuity Measurements............................... 11
4. Operation ............................................................................. 10
7. Maintenance ........................................................................ 14
3.1. Specifications ................................................................... 7
4.2. AC/DC Voltage Measurement ......................................... 11
5.2. RANGE Button ................................................................ 13
2.2. Symbols Used on LCD Display ...........................................6
4.8. Non-Contact AC Voltage Measurements ......................... 13
4.1. AC/DC Current Measurement ......................................... 10
8. Cleaning and Storage .......................................................... 14
9. Battery Replacement .......................................................... 14
3. Specifications ........................................................................ 7
5. Button ................................................................................... 13
4.5 .Capacitance Measurements ........................................... 12
4.6. Frequency or % Duty Cycle Measurements .................... 12
5.3. PEAK/VFD Button ........................................................... 13
5.5. Data Hold/Flashlight Button ............................................. 14
5.1. MODE/INRUSH Button ................................................... 13
6. Battery Replacement ........................................................... 14
4.7. Temperature Measurements ........................................... 12

This symbol, adjacent to a terminal, indicates that, under
normal use, hazardous voltages may be present.
Double insulation.
This symbol, adjacent to another symbol or terminal, indicates
the user must refer to the manual for further information.
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1. Safety
!
1.1. lnternational Safety Symbols
• When changing ranges using the selector switch always disconnect the
test leads from the circuit under test.
• Set the function switch OFF when the meter is not in use.
• Remove the battery if the meter is to be stored for long periods.
• Do not exceed the maximum rated input limits.
1.4. CAUTIONS
• Inspect the condition of the test leads and the meter itself for any
damage before operating the meter. Repair or replace if damaged before
use.
1.3. WARNINGS
• Do not exceed the maximum allowable input range of any function.
• Set function switch to the appropriate position before measuring.
1.2. SAFETY NOTES
• Do not apply voltage to meter when resistance function is selected.
• When measuring volts do not switch to current/resistance modes.
• Always remove the test leads before replacing the battery.
• Use great care when making measurements if the voltages are greater
than 25VAC RMS or 35VDC. These voltages are considered a shock
hazard.
• Improper use of this meter can cause damage, shock, injury or death.
Read and understand this user manual before operating the meter.
• Always discharge capacitors and remove power from the device under
test before performing Diode, Resistance or Continuity tests.
• Voltage checks on electrical outlets can be difficult and misleading
because of the uncertainty of connection to the recessed electrical
contacts. Other means should be used to ensure that the terminals are
not “live”.

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• If the equipment is used in a manner not specified by the manufacturer,
the protection provided by the equipment may be impaired.
2. Input Limits
4. Relative / Backlight Button
1. Current Clamp
3. Clamp Trigger
2.1. Meter Description
2. Non-Contact AC Voltage Indicator
Light
5. LCD Display
6. MODE / INRUSH Select Button
2. Description
13. COM Input Jack
7. RANGE Button
11. Battery Cover
9. Rotary Function Switch
14. VΩHz% CAP TEMP Jack
10. Data Hold / Flashlight Button
12. Flashlight
8. PEAK / VFD Button
A AC/DC
V AC/DC
Frequency, Resistance,
Diode, Continuity,
Capacitance Test
Temperature
1000A
1000V DC/AC
1000V DC/AC
1000V DC/ AC
Function Maximum Input
WARNING
TO AVOID ELECTRICAL
SHOCK REMOVE TEST
LEADS BEFORE OPENING
CASE OR BATTERY COVER.
DO NOT OPERATE WITH
BATTERY COVER OPEN.
1.5V AAAX3
1
2
3
5
4
6
7
8
9
10
11
12
13 14
V
Hz%
V
Temp
°C°F
CAP
Ω
OFF
LoZ V
Hz%
600A 1000A
AC TRMS CLAMP METER
AUTO POWER OFF
CAT III 1000V
CAT IV 600V
CAP
V Hz%
Ω
Temp
COM
REL
MODE RANGE PEAK
INRUSH

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8. Auto Range Mode
14. Variable Frequency Drive Voltage Value
15. Units of Measure List
1. Low Impedance Input Mode
5. Low Battery
9. Diode Test Mode
12. Relative Mode
16. Frequency/Duty Cycle Test Mode
11. Peak Voltage Value
4. AC (Alternating Current)
7. Auto Power Off
10. Audible Continuity
2. DC (Direct Current)
3. Minus Sign
6. Inrush Current Mode
13. Data Hold Mode
17. 6000 Count Measurement Reading
2.2. Symbols Used on LCD Display
1
3
4
7 8 910 11 12 13 14
6
15
17
16
2
5

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3.1. Specifications
3. Specifications
Range & Resolution
600.0A
1000A
Accuracy ±(% of reading+digits)
±(2.5% + 8 digits)
±(2.8% + 8 digits)
Function
AC Current
(50/60Hz)
600.0A
1000V ±(2.8% + 5 digits)
DC Current ±(2.5% + 5 digits)
Inrush current Maximum Input: 1000A.
Over range protection: Maximum input 1000A.
Frequency Response: 50Hz to 60Hz True RMS.
Accuracy specified from 5% to 100% of the measuring range.
6.000V
60.00V
600.0V
1000V
±(1.5% + 5 digits)
AC Voltage
(50-400Hz)
AC voltage bandwidth: 50 to 400Hz (Sine); 50/60 (All wave).
Maximum Input: 1000V AC RMS.
Variable frequency Drive TEST AC voltage range: 100V - 600V.
Accuracy specified from 5% to 100% of the measuring range.
VFD, PEAK Maximum Input: 1000V.
Range & Resolution
Accuracy ±(% of reading+digits)
Function
6.000V
60.00V
300.0V
±(3.0% + 40 digits)
LoZ AC
Voltage
Maximum Input: 300V AC
Range & Resolution
Accuracy ±(% of reading+digits)
Function
600.0mV
6.000V
60.00V
600.0V
1000V
±(0.5% + 5 digits)
±(1.5% + 2 digits)
DC Voltage
Maximum Input: 1000V DC
Range & Resolution
Accuracy ±(% of reading+digits)
Function

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60.00nF
600.0nF
6.000µF
60.00µF
600.0µF
6.000mF
60.00mF
100.0mF
±(4.0% + 20 digits)
±(3% + 5 digits)
±(5% + 5 digits)
±(5% + 8 digits)
±(5% + 15 digits)
Capacitance
Input Protection: 300V DC or 300V AC RMS.
Range & Resolution
Accuracy ±(% of reading+digits)
Function
600.0Ω
6.000KΩ
60.00KΩ
600.0KΩ
6.000MΩ
60.00MΩ
±(1.0% + 4 digits)
±(1.5% + 2 digits)
±(2.5% + 3 digits)
±(3.5% + 5 digits)
Resistance
Input Protection: 300V DC or 300V AC RMS.
Range & Resolution Accuracy ±(% of reading+digits) Function
Note: Accuracy is given as ±(% of reading + counts of least significant digit) at 23°C ±5°C,
with relative humidity less than 80%RH. AC voltage and current shall be subject to sine
wave.
9.999Hz to 99.99kHz ±(1.2% + 5 digits)
Frequency
Sensitivity:
=>5VRMS
Range & Resolution
Accuracy ±(% of reading+digits)
Function
10.0% to 90.0% ±(1.2% + 2 digits)
Duty Cycle
Sensitivity:
=>5VRMS
Input Protection: 300V DC or 300V AC RMS.
Range & Resolution
Accuracy ±(% of reading+digits)
Function
-20.0 to 1000°C
-4.0 to 1832°F
±(3% + 5°C)
±(3% + 9°F)
Temp
(Type-K)
(Probe accuracy not included)
Input Protection: 300V DC or 300V AC RMS.
Range & Resolution
Accuracy ±(% of reading+digits)
Function

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Clamp Size
Diode Test
Overrange Indication
TRMS
Continuity Check
Low Battery Indication
Measurements Rate
Input Impedance
Display
AC Current
AC Voltage Bandwidth
Operating Temperature
Storage Humidity
Operating Altitude
Over Voltage
Operating Humidity
Weight
Auto Off
Safety
Dimensions
Battery
Storage Temperature
3.2. General Specifications
33mm approx
2 per second, nominal
<80%
2000 meters maximum.
250 x 78 x 40mm
Three (3) x 1.5V AAA Battery
50 - 400Hz (VAC)
-20 to 60°C (-4 to 140°F)
50 - 60Hz (AAC)
Approx. 30 minutes
For indoor use and in accordance with the
requirements for double insulation to
IEC1010-1 (2001): EN61010-1 (2001)
Overvoltage Category III 1000V and Category
IV 600V, Pollution Degree 2.
10M (VDC and VAC)
5 to 40°C (41 to 104°F)
Category IV 600V
Test current of 0.3mA typical; Open circuit
voltage 3.2V DC typical.
350g
The AC voltage and AC current of this
instrument are measured by TRMS. True RMS
measurement is different from mean
measurement. The mean measurement
method can only measure the symmetric
waveform, such as sine wave. True RMS
measurements can reliably measure any
irregular waveform and obtain valid values for
AC voltage or AC current.
“OL” is displayed
6000 counts LCD
Threshold <=50Ω; Test current < 0.5mA
“ ” is displayed
Max 80% up to 31°C decreasing linearly to
50% at 40°C

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CorrectIncorrect
2. If the range to be measured is not known, select the higher range first
then move to the lower range if necessary.
3. Press the trigger to open jaw. Fully enclose one conductor to be
measured.
1. Set the Function switch to the 1000A AC/DC, 600A AC/DC range.
4. The clamp meter LCD will display the reading.
4. Operation
NOTICES: Read and understand all warning and precaution statements
listed in the safety section of this operation manual prior to using this
meter. Set the function select switch to the OFF position when the meter is
not in use.
4.1. AC Current Measurements
WARNING: Ensure that the test leads are disconnected from the meter
before making current clamp measurements.

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4. Touch the test probes to the diode under test. Forward voltage will
indicate 0.4V to 0.7V. Reverse voltage will indicate “0L”. Shorted devices
will indicate near 0mV and an open device will indicate “0L” in both
polarities.
3. Touch the test probe tips across the circuit or component under test. It is
best to disconnect one side of the device under test so the rest of the
circuit will not interfere with the resistance reading.
2. Turn the rotary switch to the Ω CAP position.
4.3. Resistance Measurements
1. Insert the black test lead into the negative COM terminal and the red
test lead into the positive terminal.
1. Insert the black test lead into the negative COM terminal and the red
test lead into the positive V terminal.
3. Connect the test leads in parallel to the circuit under test.
4. For Resistance tests, read the resistance on the LCD display.
3. Press the MODE / INRUSH button until “ “ appears in the display.
2. Set the function switch to the Ω CAP position.
1. Insert the black test lead banana plug into the negative COM jack and
the red test lead banana plug into the positive diode jack.
2. Set the function switch to the ACV or DCV position.
4.2. AC/DC Voltage Measurements
4.4. Diode and Continuity Measurements
4. Read the voltage measurement on the LCD display.
Forward Test Reverse Test
Red
Probe Black Probe Black Probe Red Probe
For Continuity tests, if the resistance is < 50Ω, a tone will sound.

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2. Insert the black test lead banana plug into the negative COM jack.
Insert the red test lead banana plug into the positive V jack.
4.7. Temperature Measurements
1. Set the function switch to TEMP.
4.6. Frequency or % Duty Cycle Measurements
1. Set the rotary function switch to the “VAC/Hz/%” position.
1. Set the rotary function switch to the Ω CAP position.
3. Press the MODE / INRUSH button to change to capacitance
measurements.
WARNING: To avoid electric shock, disconnect power to the unit under
test and discharge all capacitors before taking any capacitance
measurements. Remove the batteries and unplug the line cords.
3. Select Hz or % duty with the MODE / INRUSH button.
4.5. Capacitance Measurements
5. Read the capacitance value in the display.
2. Insert the black lead banana plug into the negative COM jack and the
red test lead banana plug into the positive V jack.
4. Touch the test probe tips to the circuit under test.
4. Touch the test leads to the capacitor to be tested.
5. Read the frequency on the display.
WARNING: To avoid electric shock, disconnect both test probes from
any source of voltage before making a temperature measurement.
2. Insert the Temperature Probe into the negative COM and the V jacks,
making sure to observe the correct polarity.
3. Touch the Temperature Probe head to the part whose temperature you
wish to measure. Keep the probe touching the part under test until the
reading stabilizes (about 30 seconds).
4. Read the temperature in the display. The digital reading will indicate the
proper decimal point and value.
WARNING: To avoid electric shock, be sure the thermocouple has been
removed before changing to another measurement function.

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5.3. PEAK/VFD (Variable Frequency Drive) Button
In the AC voltage mode, Press the PEAK/VFD key to display “----” first
and then enter the PEAK measurement mode. The maximum PEAK and
minimum PEAK voltage can be measured circularly.
Hold down the button to enter the VFD function measurement. In the
VFD mode, the voltage value of the variable frequency drive device can
be measured. The measured values of “PEAK” and “VFD” are for
reference only.
NOTE: The conductors in electrical cord sets are often twisted. For best
results, rub the probe tip along a length of the cord to assure placing
the tip in close proximity to the live conductor.
5. Button
5.1.MODE/INRUSH Button
4.8. Non-Contact AC Voltage Measurements
WARNING: Risk of Electrocution. Before use, always test the Voltage
Detector on a known live circuit to verify proper operation
1. Touch the probe tip to the live conductor or insert into the live side of
the electrical outlet.
2. If AC voltage is present, the detector light will illuminate.
NOTE: The detector is designed with high sensitivity. Static electricity or
other sources of energy may randomly trip the sensor. This is normal
operation.
To select ACV / Hz / %; OHM / Continuity / Diode / CAP; °C / °F,
ACA/DCA.
5.2.RANGE Button
When the meter is first turned on, it automatically goes into Auto
Ranging. This automatically selects the best range for the
measurements being made and is generally the best mode for most
measurements. For measurement situations requiring that a range be
manually selected, perform the following:
1. Press the RANGE button. The “Auto Range” display indicator will turn
off, The “Manual Range” display indicator will turn on.
2. Press the RANGE button to step through the available ranges until you
select the range you want.
3. Press and hold the RANGE button for 2 seconds to exit the Manual
Ranging mode and return to Auto Ranging.

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5.5. Data Hold / Flashlight Button
4. Re-assemble the meter.
REL for DCA and Capacitance Zero & Offset adjustment. Hold down this
button to turn the backlight ON and OFF.
3. Replace the Requires Three “AAA” 1.5V Battery.
5.4. REL /Backlight Button
2. Open the battery compartment.
1. To freeze the LCD meter reading, press the data hold button. The data
hold button is located on the right side of the meter (top button). While
data hold is active, the H display icon appears on the LCD. Press the
data hold button again to return to normal operation.
2. Hold down this button to turn the flashlight ON and OFF.
6. Battery Replacement
1. Remove the one rear head screw.
10. Temperature Probe Replacement
2. The replacement temperature adaptor (with banana plug) is part number
MT802.
1. Periodically wipe the case with a damp cloth and mild detergent; do not
use abrasives or solvents. If the meter is not to be used for 60 days or
more, remove the battery and store it separately.
1. Rotate battery door lock 180 degrees to open the battery door
9. Battery Replacement
7. Maintenance
WARNING: To avoid electrical shock, disconnect the meter from any
circuit, remove the test leads from the input terminals, and turn OFF the
meter before opening the case. Do not operate the meter with an open
case.
2. Open the battery compartment
8. Cleaning and Storage
3. Replace the 3 x 1.5V AAA battery
4. Secure the battery compartment
1. The replacement bead wire probe (with K-Type plug) is part number
MT660.

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MAJOR TECH (PTY) LTD
T9 Industrial Village, Sam Green Road, 7
Tunney Ext. 9, , Elandsfontein
South Africa
P.O. Box 888, Isando 1600,
South Africa
Telephone: [phone]
National Contact Number: 08 61 62 5678
E-mail: [email protected]
www.major-tech.com