Major tech MT785 User manual

MT785
1000 A AC/DC TRMS
POWER CLAMP METER

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Contents Page no
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1. Safety
1.1. International Safety Symbols
This symbol adjacent to another symbol, terminal or
operating device indicates that the operator must
refer to an explanation in the Operating Instructions
to avoid personal injury or damage to the meter.
!
This symbol adjacent to one or more terminals
identifies them as being associated with ranges that
may, in normal use, be subjected to particularly
hazardous voltages. For maximum safety, the meter
and its test leads should not be handled when these
terminals are energized.
Equipment is protected by double or reinforced
insulation
1.2. Safety Notes
Ÿ Do not exceed the maximum allowable input range of any function.
Ÿ Do not apply voltage to meter when resistance function is selected.
Ÿ Set the function switch OFF when the meter is not in use.
Ÿ Remove the battery if meter is to be stored for longer than 60 days.
1.3. Warnings
Ÿ Set function switch to the appropriate position before measuring.
Ÿ When measuring volts do not switch to current/resistance modes.
Ÿ Do not measure current on a circuit whose voltage exceeds 600V.
Ÿ When changing ranges always disconnect the test leads from the
circuit under test.
1.4. Cautions
Ÿ Improper use of this meter can cause damage, shock, injury or death.
Read and understand this user manual before operating the meter.
Ÿ Always remove the test leads before replacing the battery or fuses.
Ÿ Inspect the condition of the test leads and the meter itself for any
damage before operating the meter. Repair or replace any damage
before use.
Ÿ Use great care when making measurements if the voltages are
greater than 25VAC RMS or 35VDC. These voltages are considered a
shock hazard.
Ÿ Always discharge capacitors and remove power from the device under
test before performing Diode, Resistance or Continuity tests.
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Cautions cont.
Ÿ 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".
Ÿ If the equipment is used in a manner not specified by the manufacturer,
the protection provided by the equipment may be impaired.
A AC, A DC 1000A AC
Maximum
Input
Function
1000V DC/AC
600V DC/AC
600V DC/ AC
V DC, V AC
Resistance, Capacitance, Frequency,
Diode Test
Temperature
2. Description
2.1. Meter Description
1. Current clamp
2. Flash light LED
3. Non-contact AC voltage
indicator light
4. Flash light button
5. Clamp trigger
6. Rotary Function switch
7. Data Hold and Backlight button
8. MODE select button
9. PEAK and INRUSH button
10. Max/Min button
11. RANGING button
12. LCD display
13. COM input jack
14. V ΩCAP TEMP Hz jack
15. Battery Cover
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1
__________2
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5
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7
________
8
________
12
_________
13
__________
10
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___________15
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_________14
_______9
__________11
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________6
______4
__________3

2.2 Display icons Description
HOLD Data Hold
- Negative Reading Display
0 to 3999 Measurement display digits
MAX/MIN Maximum/Minimum
REL/DCA Zero
Auto Power Off
AUTO Auto Range Mode
DC/AC Direct Current / Alternating
Current
Low Battery
mV or V Milli-volts or Volts (Voltage)
Ohms (Resistance)
A Amperes (Current)
F Farad (Capacitance)
Hz/% Hertz (Frequency)/
Percent (duty ratio)
C° and F° Celsius and Fahrenheit units
(Temperature)
n, m, μ, M, k Unit of measure prefixes: nano, milli, micro
Continuity Test
Diode Test
THD THD Test
Individual Harmonic mode
Select Mode
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3. SPECIFICATIONS
Voltage
Function Range Resolution Accuracy
(% of reading + digits)
DC Voltage
6.000V
60.00V
600.0V
1000V
1mV
10mV
100mV
1V
+1.0% of rdg + 3digits
+1.2% of rdg + 3digits
+1.2% of rdg + 3digits
+1.5% of rdg + 3digits
Function Range Resolution Accuracy
(% of reading + digits)
AC True RMS Voltage
6.000V
60.00V
600.0V
1000V
1mV
10mV
100mV
1V
+1.2% of rdg + 5digits
+1.2% of rdg + 5digits
+1.5% of rdg + 5digits
+3% of rdg + 8digits
Maximum Input: 1000V DC
AC Response: 50 Hz to 400Hz
Not sinusoidal waveform Accuracy:(60Hz to 400Hz) : (10%rdg + 10dgt)
Maximum Input: 1000V ac rms.
Function Range Resolution Accuracy
(% of reading + digits)
AC +DC
6.000V
60.00V
600.0V
1000V
1mV
10mV
100mV
1V
+1.5% of rdg + 5digits
+1.5% of rdg + 5digits
+1.5% of rdg + 5digits
+3% of rdg + 8digits
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Function Range Resolution Accuracy
(% of reading + digits)
DC A
60A
1000A
60A
1000A
10mA
100mA
10mA
100mA
±(2.5% of reading + 0.2A)
±(2.5% of reading + 5digits)
50-60Hz ±(2.5% of reading + 8digits)
AC A
Current
Function Range Resolution Accuracy
Frequency 20Hz-10kHz 0.1Hz ±(0.5% of reading + 3digits)
Frequency
Function Range Resolution Accuracy
AC A/AC V 99.9% 0.1% ±(3% of reading + 10digits)
Total Harmonic Distortion
Harmonic distortion measurement
Function Range Resolution Accuracy
H01-H12 99.9% 0.1% ±(5% of reading + 10digits)
±(10% of reading + 10digits)
Active Power
Function Range Accuracy
AC W 599.9KW
ACA Sensitivity: >10A RMS
DCV Sensitivity : >5V MAX 600V
A.error x v.reading+
V.error x A.reading
H13-H25
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Power Factor
Function Range Accuracy
PF -1.0-0.0-1.0 ±(3% of reading + 1digits)
Function Range Resolution Accuracy
Resistance
Resistance & Continuity & Diode
600.0Ω
6.000kΩ
60.00kΩ
600.0kΩ
6.000MΩ
60.00MΩ
0.1Ω
1Ω
10Ω
100Ω
1kΩ
10kΩ
±(1.0% of reading + 5digits)
±(1.5% of reading + 3digits)
±(1.5% of reading + 3digits)
±(1.5% of reading + 3digits)
±(2.0% of reading + 5digits)
±(3% of reading + 8digits)
Function Range Resolution Accuracy
Capacitance
Capacitance
9.999uF
99.99uF
999.9uF
9999uF
1nF
10nF
0.1uF
1uF
±(3% of reading + 5digits)
±(3% of reading + 5digits)
±(4% of reading + 10digits)
±(4.5% of reading + 10digits)
Function Range Resolution Accuracy
Temperature
Temperature
-50°C ----
+599.9°C
600°C ----
+1000°C
-58°F ----
+599.9°F
600°F ----
+1832°F
0.1°C
1°C
0.1°F
1°F
±(3% of reading + 5°C)
±(3% of reading + 5°C)
±(3% of reading + 9°F)
±(3% of reading + 9°F)
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Function Testing Condition Reading
Diode
Diode and Continuity
Forward DCA is approx.1mA,
open circuit Voltage MAX . 3V
Test current MAX. 1.5mA
Forward voltage drop of Diode
Buzzer makes a long sound,
While resistance is less than(50)
Continuity
4. General Specifications
Clamp jaw opening 1.9" (48mm) approx.
Flexible coil φ140*180mm
Display 3-6/7 digits (6000 counts) backlit LCD
Threshold 50Ω; Test current <0.5mA
Continuity check
Low Battery indication is displayed
Over-range indication 'OL' display
Measurement rate 3 readings per second, nominal
PEAK Captures peaks >1ms
INRUSH 100MS
Temperature sensor Type K thermocouple
Input Impedance 10MΩ (VDC and VAC)
AC response True RMS (A AC and V AC)
Operating Temperature 5°C to 40°C (41°F to 104°F)
Storage Temperature -20°C to 60°C (-4°F to 140°F)
Operating Humidity Max 80% up to 31°C (87°F) decreasing
linearly to 50% at 40°C (104°F)
Storage Humidity <80%
Operating Altitude 2000meters (7000ft.) maximum.
Battery One (1) 9V Battery
Auto power OFF After approx. 30 minutes
Dimensions & Weight 230 x 76 x 40mm; 315g
Safety 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
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5. OPERATION
Notes
Read and understand all WARNING and CAUTION statements in this
operation manual prior to using this meter. Set the function select switch
to the OFF position when the meter is not in use.
5.1. AC/DC Current Measurements
WARNING: Ensure that the test leads are disconnected from the meter
before making current clamp measurements.
1. Set the Function switch to the 1000A, 600A or 60A range. If the
approx. range of the measurement is not known, select the highest
range then move to the lower ranges if necessary.
2. Press the ZERO button to zero the meter display.
3. Use the MODE button to select AC or DC Current.
4. Press the trigger to open jaw. Fully enclose only one conductor. For
optimum results, center the conductor in the jaw.
5. The clamp meter LCD will display the reading.
NOTE: Press ZERO button to test DC Current Measurements .
5.2. AC Voltage Measurement
1. Insert the black test lead into the negative COM terminal and the
red test lead into the positive V CAP TEMP Hz Ω terminal. G
2. Set the function switch to the V~ position.
3. Connect the test leads in parallel to the circuit under test.
4. Read the voltage measurement on the LCD display.
5.3. DC Voltage Measurement
1. Insert the black test lead into the negative COM terminal and the
red test lead into the positive V CAP TEMP Hz Ω terminal.G
2. Set the function switch to the V- position.
3. Connect the test leads in parallel to the circuit under test.
4. Read the voltage measurement on the LCD display.
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5.4. Resistance
1. Insert the black test lead into the negative COM terminal and the
red test lead into the V CAP TEMP Hz Ω positive terminal. G
))
2. Set the function switch to the Ω ).CAP position. G
3. Touch the test probe tips across the circuit or component under
test.
4. Read the resistance on the LCD display.
5.5. Capacitance Measurements
))
1. Set the function switch to the Ω ).CAP position. G
2. Insert the black test lead banana plug into the negative COM jack
and the red test lead banana plug into the V CAP TEMP Hz Ω· G
positive jack.
3. Touch the test probe tips across the part under test. If “OL” appears
in the display, remove and discharge the component.
4. Read the capacitance value in the display.
5. The display will indicate the proper decimal point and value.
Note: For very large values of capacitance measurement it can take
several minutes before the final reading stabilizes.
WARNING: To avoid electric shock, discharge the capacitor under test
before measuring.
5.6. Frequency Measurements
1. Insert the black test lead banana plug into the negative COM jack
and the red test lead banana plug into the V CAP TEMP Hz Ω G
positive jack.
2. Set the function switch to the AC V/AC A Position.
3. Touch the test probe tips across the part under test.
4. Read the value on the display.
5. The display will indicate the proper decimal point and value.
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1. Insert the black test lead into the negative COM terminal and the
red test lead into the V CAP TEMP Hz Ω positive terminal. G
2. Set the function switch to the Ω CAP position.
))
G ).
3. Use the MODE button to select continuity “ “ The display icons
will change when the MODE button is pressed.
4. Touch the test probe tips across the circuit or component under
test.
5. If the resistance is < 50Ω, a tone will sound.
5.7. Temperature Measurements
1. Set the function switch to the TEMP position.
2. Insert the Temperature Probe into the negative COM and the
V CAP TEMP Hz Ω positive jacks, observing polarity. G
3. Touch the Temperature Probe head to the device under test.
Continue to touch the part under test with the probe until the
reading stabilizes.
4. Read the temperature on the display. The digital reading will
indicate the proper decimal point and value.
5. Use the MODE button to select °C or °F.
WARNING: To avoid electric shock, be sure the thermocouple
probe has been removed before changing to another measurement
function.
5.8. Continuity Measurements
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5.9. Diode Test
1. Insert the black test lead banana plug into the negative COM jack
and the red test lead banana plug into the V CAP TEMP Hz Ω G
positive jack
2. Turn the function switch to Ω CAP. Use the MODE
))
G ).
button to select the diode function if necessary (diode symbol will
appear on the LCD when in Diode test mode)
3. Touch the test probe tips to the diode or semiconductor junction
under test. Note the meter reading
4. Reverse the test lead polarity by reversing the red and black leads.
Note this reading
5. The diode or junction can be evaluated as follows:
• If one reading displays a value (typically 0.400V to 0.900V) and
the other reading displays OL, the diode is good.
• If both readings display OL the device is open.
• If both readings are very small or '0', the device is shorted.
5.10. THD Measurement (AC mode only)
Select the “THD” indicator then press the MODE key to enter the THD
mode. THD-F=RMS of Harmonics ÷ RMS of fundamental ×100%.
(harmonics up to the 50th)
5.11. Individual Harmonic Measurement (AC mode only)
Select the “ “ indicator then press the mode key to enter the
individual harmonic mode. Select the “Hn “ indicator then press the
and key to enter the individual harmonic mode. Hn=RMS of
Individual Harmonic ÷ RMS of fundamental ×100%.
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5.12. Measuring Active Power (W) / Power factor (PF)
Step 1: Set the rotary switch to the “W” position.
Step 2: Connect the Red test lead to the Line conductor, and the Black
test lead to the Neutral conductor.
Step 3: Press the trigger to open the transformer jaws and clamp one
conductor only, make sure that the jaw is firmly closed around
the conductor.
Step 4: Using the Mode key to choose the “W/PF” mode.
Note: The meter offer AC power measurement mode only.
1. Single Phase Power Measurement
Active power sign :
No sign : Indicates the power flows from the power source to the
load.
“_” sign : Indicates the power flows from the load to the power
source.
Power factor sign :
No sign : The phase of the current signal is lagging behind the
voltage signal (inductive load).
“_” sign : The phase of the current signal is leading the voltage
signal (capacitive load).
Overrange display :
± OL kW : Active Power >600 kW or < -600 kW.
OLU: Active Power >600 V or < -600 V.
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The AUTORANGE mode automatically selects the proper range for the
measurement being made and is generally the best mode for most
applications. For measurement situations requiring that a range be manually
selected, perform the following:
1. Momentarily press the RANGE button. The “AUTO” indicator will
no longer be shown on the LCD display.
2. Momentarily press the RANGE button to step through the available
ranges until the desired range is selected.
3. To exit the Manual Ranging mode, press and hold the RANGE
button until the “AUTO” indicator reappears.
The Autorange mode automatically selects the proper range for the
measurement being made and is generally the best mode for most
applications. For measurement situations requiring that a range be manually
selected, perform the following:
1. Momentarily press the RANGE button. The “AUTO” indicator will
no longer be shown on the LCD display.
2. Momentarily press the RANGE button to step through the available
ranges until the desired range is selected.
3. To exit the Manual Ranging mode, press and hold the RANGE
button until the “AUTO” indicator reappears.
5.13. RANGE button
Press MODE key the selection of double measured functions which are
present at display is possible. In particular this key is active in V CAP Ω G
position to select among resistance test, diode test, continuity test and
capacitance test, and in Temp position to select between °C or °F. and in
current position to select between AC or DC current measurements and
THD test.
To press and hold the MODE key to turn the system on, the auto power off
function will be cancelled.
NOTE: Only ACV functions can do the peak value measurement.
PEAK Key is the peak value measurement key that acts with trigger.
6. Mode
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NOTE: Only AC A functions can do the INRUSH value measurement.
1. Switch off motor and then clamp supply.
2. Press the INRUSH button , “----”will appear in the display.
3. Start motor and then read the value on the display.
INRUSH
To freeze the LCD reading, press the HOLD button. While data hold is active,
the HOLD icon appears on the LCD. Press the HOLD button again to return
to normal operation.
Data Hold
Press MAX/IN key the maximum and minimum values are measured.
This mode is activated on each measurement except for continuity test,
diode test capacitance test, frequency test and duty cycle test.
This mode is disabled keeping pressed MAX/MIN key or moving the
rotary switch.
MAX/MIN
Press the Flash light button to turn the flash light on. Press again to turn
the flash light off.
Flash Light Button
The LCD is equipped with backlighting for easier viewing, especially in
dimly lit areas. Press the backlight button to turn the backlight on. Press
again to turn the backlight off. Note that the meter does have an auto
power off feature as described below.
LCD Backlight Button
In order to conserve battery life, the meter will automatically turn off
after approximately 15 minutes. To turn the meter on again, turn the
function switch to the OFF position and then to the desired function
position.
Automatic Power OFF
17
Bluetooth Off: Bluetooth logo is not displayed on the screen
Bluetooth On: Bluetooth logo is displayed on screen
Hold down the mode button to select the bluetooth function
Bluetooth
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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.
7. MAINTENANCE
Cleaning and Storage
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.
Battery Replacement
1. Remove the Phillips head screw that secures the rear battery door
2. Open the battery compartment
3. Replace the 9V battery
4. Secure the battery compartment
Temperature Probe Replacement
NOTE: To use a K Type thermocouple probe that is terminated by a
subminiature (flat blade) connector, a subminiature-to-banana plug
adaptor (Part Number MT660 & MT802) is required.
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South Africa Australia