MAJOR TECH MT785 1000 A AC/DC Trms Power Clamp Meter User Manual
- June 4, 2024
- MAJOR TECH
Table of Contents
MAJOR TECH MT785 1000 A AC/DC Trms Power Clamp Mete
Safety
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
Safety Notes
- Do not exceed the maximum allowable input range of any function.
- Do not apply voltage to meter when resistance function is selected.
- Set the function switch OFF when the meter is not in use.
- Remove the battery if meter is to be stored for longer than 60 days. 1.3.
Warnings
- Set function switch to the appropriate position before measuring.
- When measuring volts do not switch to current/resistance modes.
- Do not measure current on a circuit whose voltage exceeds 600V.
- When changing ranges always disconnect the test leads from the circuit under test.
Cautions
- Improper use of this meter can cause damage, shock, injury or death. Read and understand this user manual before operating the meter.
- Always remove the test leads before replacing the battery or fuses.
- 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.
- Use great care when making measurements if the voltages are greater than 25VAC RMS or 35VDC. These voltages are considered a shock hazard.
- Always discharge capacitors and remove power from the device under
Cautions cont.
- 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”.
- If the equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be impaired.
Function | Maximum Input |
---|---|
A AC, A DC | 1000A AC |
V DC, V AC | 1000V DC/AC |
Resistance, Capacitance, Frequency, Diode Test | 600V DC/AC |
Temperature | 600V DC/ AC |
Description
Meter Description
- Current clamp
- Flash light LED
- Non-contact AC voltage indicator light
- Flash light button
- Clamp trigger
- Rotary Function switch
- Data Hold and Backlight button
- MODE select button
- PEAK and INRUSH button
- Max/Min button
- RANGING button
- LCD display
- COM input jack
- V ΩCAP TEMP Hz jack
- Battery Cover
Display icons Description
- HOLD Data Hold
- Negative Reading Display
- Measurement display digits Maximum/Minimum
- REL/DCA Zero
- Auto Power Off
- Auto Range Mode
- Direct Current / Alternating Current
- Low Battery
- Milli-volts or Volts (Voltage)(Resistance)
- Amperes (Current)
- Farad (Capacitance)
- Hertz (Frequency)/Percent (duty ratio)
- Celsius and Fahrenheit units (Temperature)
- Unit of measure prefixes: nano, milli, micro
- Continuity Test
- Diode Test
- THD THD Test
- Individual Harmonic mode Select Mode
SPECIFICATIONS
Voltage
Function| Range| Resolution| Accuracy
(% of reading + digits)
---|---|---|---
DC Voltage
| 6.000V| 1mV| +1.0% of rdg + 3digits
60.00V| 10mV| +1.2% of rdg + 3digits
600.0V| 100mV| +1.2% of rdg + 3digits
1000V| 1V| +1.5% of rdg + 3digits
Maximum Input: 1000V DC ****
Function| Range| Resolution| Accuracy
(% of reading + digits)
---|---|---|---
AC True RMS Voltage
| 6.000V| 1mV| +1.2% of rdg + 5digits
60.00V| 10mV| +1.2% of rdg + 5digits
600.0V| 100mV| +1.5% of rdg + 5digits
1000V| 1V| +3% of rdg + 8digits
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| 1mV| +1.5% of rdg + 5digits
60.00V| 10mV| +1.5% of rdg + 5digits
600.0V| 100mV| +1.5% of rdg + 5digits
1000V| 1V| +3% of rdg + 8digits
Current
Function| Range| Resolution| Accuracy
(% of reading + digits)
---|---|---|---
DC A
| 60A| 10mA| ±(2.5% of reading + 0.2A)
1000A| 100mA| ±(2.5% of reading + 5digits)
AC A| 60A| 10mA| 50-60Hz ±(2.5% of reading + 8digits)
1000A| 100mA
Frequency
Function | Range | Resolution | Accuracy |
---|---|---|---|
Frequency | 20Hz-10kHz | 0.1Hz | ±(0.5% of reading + 3digits) |
Total Harmonic Distortion
Function | Range | Resolution | Accuracy |
---|---|---|---|
AC A/AC V | 99.9% | 0.1% | ±(3% of reading + 10digits) |
Harmonic distortion measurement
Function | Range | Resolution | Accuracy |
---|---|---|---|
H01-H12 | 99.9% | 0.1% | ±(5% of reading + 10digits) |
H13-H25 | ±(10% of reading + 10digits) |
ACA Sensitivity: >10A RMS
DCV Sensitivity : >5V MAX 600V
Active Power
Function | Range | Accuracy |
---|---|---|
AC W | 599.9KW | A.error x v.reading+ V.error x A.reading |
Power Factor
Function | Range | Accuracy |
---|---|---|
PF | -1.0-0.0-1.0 | ±(3% of reading + 1digits) |
Resistance & Continuity & Diode
Function | Range | Resolution | Accuracy |
---|---|---|---|
Resistance | 600.0Ω | 0.1Ω | ±(1.0% of reading + 5digits) |
6.000kΩ | 1Ω | ±(1.5% of reading + 3digits) | |
60.00kΩ | 10Ω | ±(1.5% of reading + 3digits) | |
600.0kΩ | 100Ω | ±(1.5% of reading + 3digits) | |
6.000MΩ | 1kΩ | ±(2.0% of reading + 5digits) | |
60.00MΩ | 10kΩ | ±(3% of reading + 8digits) |
Capacitance
Function | Range | Resolution | Accuracy |
---|---|---|---|
Capacitance | 9.999uF | 1nF | ±(3% of reading + 5digits) |
99.99uF | 10nF | ±(3% of reading + 5digits) | |
999.9uF | 0.1uF | ±(4% of reading + 10digits) | |
9999uF | 1uF | ±(4.5% of reading + 10digits) |
Temperature
Function | Range | Resolution | Accuracy |
---|---|---|---|
Temperature | -50°C —- |
+599.9°C
| 0.1°C| ±(3% of reading + 5°C)
±(3% of reading + 5°C)
600°C —-
+1000°C
| 1°C
-58°F —-
+599.9°F
| 0.1°F| ±(3% of reading + 9°F)
±(3% of reading + 9°F)
600°F —-
+1832°F
| 1°F
Diode and Continuity
Function | Testing Condition | Reading |
---|---|---|
Diode | Forward DCA is approx.1mA, open circuit Voltage MAX . 3V | Forward |
voltage drop of Diode
Continuity| Test current MAX. 1.5mA| Buzzer makes a long sound, While
resistance is less than(50)
General Specifications
- Clamp jaw opening 1.9″ (48mm) approx.
- Flexible coil φ140*180mm
- Display 3-6/7 digits (6000 counts) backlit LCD
- Continuity check Threshold 50Ω; Test current <0.5mA
- 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
- 10 Category IV 600V, Pollution Degree 2
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.
AC/DC Current Measurements
WARNING: Ensure that the test leads are disconnected from the meter before making current clamp measurements.
- 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.
- Press the ZERO button to zero the meter display.
- Use the MODE button to select AC or DC Current.
- Press the trigger to open jaw. Fully enclose only one conductor. For optimum results, center the conductor in the jaw.
- The clamp meter LCD will display the reading.
NOTE: Press ZERO button to test DC Current Measurements
AC Voltage Measurement
- Insert the black test lead into the negative COM terminal and the red test lead into the positive V G CAP TEMP Hz Ω terminal.
- Set the function switch to the V~ position.
- Connect the test leads in parallel to the circuit under test.
- Read the voltage measurement on the LCD display.
DC Voltage Measurement
- Insert the black test lead into the negative COM terminal and the red test lead into the positive V G CAP TEMP Hz Ω terminal.
- Set the function switch to the V- position.
- Connect the test leads in parallel to the circuit under test.
- Read the voltage measurement on the LCD display.
Resistance
- Insert the black test lead into the negative COM terminal and the red test lead into the V G CAP TEMP Hz Ω positive terminal.
- Set the function switch to the Ω G ))).CAP position.
- Touch the test probe tips across the circuit or component under test.
- Read the resistance on the LCD display.
Capacitance Measurements
WARNING : To avoid electric shock, discharge the capacitor under test before measuring.
- Set the function switch to the Ω G ))).CAP position.
- Insert the black test lead banana plug into the negative COM jack and the red test lead banana plug into the V G CAP TEMP Hz Ω· positive jack.
- Touch the test probe tips across the part under test. If “OL” appears in the display, remove and discharge the component.
- Read the capacitance value in the display.
- 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.
Frequency Measurements
- Insert the black test lead banana plug into the negative COM jack and the red test lead banana plug into the V G CAP TEMP Hz Ω positive jack.
- Set the function switch to the AC V/AC A Position.
- Touch the test probe tips across the part under test.
- Read the value on the display.
- The display will indicate the proper decimal point and value.
Temperature Measurements
- Set the function switch to the TEMP position.
- Insert the Temperature Probe into the negative COM and the V G CAP TEMP Hz Ω positive jacks, observing polarity.
- Touch the Temperature Probe head to the device under test. Continue to touch the part under test with the probe until the reading stabilizes.
- Read the temperature on the display. The digital reading will indicate the proper decimal point and value.
- 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
Continuity Measurements
- Insert the black test lead into the negative COM terminal and the red test lead into the V G CAP TEMP Hz Ω positive terminal.
- Set the function switch to the Ω G ))).CAP position.
- Use the MODE button to select continuity “ “ The display icons will change when the MODE button is pressed.
- Touch the test probe tips across the circuit or component under test.
- If the resistance is < 50Ω, a tone will sound.
Diode Test
- Insert the black test lead banana plug into the negative COM jack and the red test lead banana plug into the V G CAP TEMP Hz Ω positive jack
- Turn the function switch to Ω G ))).CAP. Use the MODE button to select the diode function if necessary (diode symbol will appear on the LCD when in Diode test mode)
- Touch the test probe tips to the diode or semiconductor junction under test. Note the meter reading
- Reverse the test lead polarity by reversing the red and black leads. Note this reading
- 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.
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)
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%.
Measuring Active Power (W) / Power factor (PF)
Single Phase Power Measurement
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.
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.
RANGE button
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:
- Momentarily press the RANGE button. The “AUTO” indicator will no longer be shown on the LCD display.
- Momentarily press the RANGE button to step through the available ranges until the desired range is selected.
- 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:
- Momentarily press the RANGE button. The “AUTO” indicator will no longer be shown on the LCD display.
- Momentarily press the RANGE button to step through the available ranges until the desired range is selected.
- To exit the Manual Ranging mode, press and hold the RANGE button until the “AUTO” indicator reappears.
Mode
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 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.
INRUSH
NOTE : Only AC A functions can do the INRUSH value measurement.
- Switch off motor and then clamp supply.
- Press the INRUSH button , “—-”will appear in the display.
- Start motor and then read the value on the display.
Data Hold
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.
MAX/MIN
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.
Flash Light Button
Press the Flash light button to turn the flash light on. Press again to turn
the flash light off.
LCD Backlight 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.
Bluetooth
- 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
Automatic Power OFF
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.
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.
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
- Remove the Phillips head screw that secures the rear battery door
- Open the battery compartment
- Replace the 9V battery
- 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.