Major tech MT25 User manual

25 YEAR SPECIAL EDITION
MT25
600V AC/DC
MULTIMETER
INSTRUCTION MANUAL

2

Contents Page no
3
1. Introduction............................................................................................ 4
1.1. Warnings............................................................................................4
1.2. Input Limits.........................................................................................4
2. Safety Symbols.......................................................................................5
2.1. Safety Category Ratings....................................................................5
2.2. Warnings............................................................................................5
3. Meter Description...................................................................................6
4. Symbols Used on LCD Display ..............................................................6
5. Operation................................................................................................7
5.1. Auto Power Off...................................................................................7
5.2. MODE Button.....................................................................................7
5.3. MAX MIN Button.................................................................................7
5.4. Flashlight Button................................................................................7
5.5. HOLD/Backlight Button......................................................................7
5.6. AC/DC Voltage Measurement............................................................8
5.7. Frequency & % Duty Cycle Measurements.........................................8
5.8. AC Current Measurement..................................................................8
5.9. DC Current Measurements................................................................9
5.10. Resistance Measurements..............................................................9
5.11. Diode Test........................................................................................9
5.12. Continuity.......................................................................................10
5.13. Capacitance Measurements..........................................................10
5.14. Temperature Measurements..........................................................10
5.15. Battery Replacement......................................................................11
5.16. Fuse Replacement.........................................................................11
6. Maintenance..........................................................................................11
7. General Specifications.........................................................................12
8. Specifications.......................................................................................13

1. Introduction
The MT25 Digital Multimeter is a compact handheld unit that provides fast and
accurate measurements on an oversized, high contrast LCD display with a
bargraph & backlight. The housing is double moulded plastic, for safety &
durability. With multiple functions that include AC/DC voltage, AC/DC current,
resistance, continuity, capacitance, frequency, duty cycle, temperature and diode
test. The MT25 also offers the added convenience of a built-in LED flashlight and
a tilt stand.
1.1. Warnings
·Read, understand and follow Safety Rules and Operating Instructions in this
manual before using this meter.
·The meter's safety features may not protect the user if not used in
accordance with the manufacturer's instructions.
·and keep fingers Ensure that the test leads are fully seated in the input jacks
away from the metal probe tips when taking measurements.
·Before changing functions using the selector switch, always disconnect the
test leads from the circuit under test.
·Use only Major Tech approved test leads with the proper safety category
rating.
·Comply with all applicable safety codes. Use approved personal protective
equipment when working near live electrical circuits - particularly with regard
to arc-flash potential.
·Use caution on live circuits. Voltages above 30V AC, 42V AC peak, or 60V DC
pose a shock hazard.
·Do not use if the meter or test leads appear damaged.
·Verify operation before using meter by measuring a known live voltage.
·Do not use the meter in wet or damp environments or during electrical
storms.
·Do not use the meter near explosive vapors, dust or gasses.
·Do not use the meter if it operates incorrectly. The protection may be
compromised.
·Do not operate meter while Low Battery warning is on. Replace batteries
immediately.
·Do not apply voltage or current that exceeds the meter's maximum rated
input limits.
1.2. Input Limits
Maximum Input
600V AC RMS/600V DC
10A/600V AC RMS/600V DC (30 seconds
max. every 15 minutes in the 10A range)
250V AC RMS/250V DC
Function
Voltage AC or DC
Current AC or DC
Resistance, Continuity, Diode Test,
Capacitance, Frequency, Duty Cycle
Temperature 250V AC/250V DC
4

2. 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
MAX Indicates the terminal(s) so marked must not be connected to a circuit
where the voltage with respect to earth ground exceeds the maximum
safety rating of the meter.
2.1. Safety Category Ratings
Category
Rating
Brief
Description Typical Applications
CAT II Single phase
receptacles
and connected
loads
• Household appliances, power tools
• Outlets more than 10m (30ft) from a CAT III
source
• Outlets more than 20m (60ft) from a CAT IV
source
CAT III Three phase
circuits and
single phase
lighting circuits
in commercial
buildings
• Equipment in fixed installations such as 3- phase
motors, switchgear and distribution panels
• Lighting circuits in commercial buildings
• Feeder lines in industrial plants
• Any device or branch circuit that is close to a
CAT III source
The measurement category (CAT) rating and voltage rating is determined by a
combination of the meter, test probes and any accessories connected to the meter
and test probes. The combination rating is the LOWEST of any individual
component.
2.2. Warning
Operation is limited to CAT II applications when the insulated tips are removed
from one or both test probes. Refer to Input Limits section in this manual for
maximum voltage ratings.
CAT IV 600V
CAT III 1000V
TEST LEADS
5

3. Meter Description
1. LCD display
2. MAX/MIN button
3. MODE button
4. Rotary function switch
5. 10A input jack
6. COM input jack
7. V/Ω/°F °C input jack
8. HOLD Backlight button
9. Flashlight button
10. Flashlight
6
4. Symbols Used on LCD Display
Degress Farenheit
Degrees Celcius
-6
micro (10 )
-3
milli (10 )
-3
kilo (10 )
-6
mega (10 )
Overload
Auto Power Off
Low battery
Autoranging
Display hold
Maximum/Minimum
Volts
Amperes
Alternating current
Direct current
Minus sign
Hertz (frequency)
Percent (duty cycle)
Ohms
Continuity
Diode test
Farads (capacitance)
-9
nano (10 )
V
A
~
Hz
%
F
N
Ω
°F
°C
m
k
M
OL
+ -
AUTO
HOLD
MAX/MIN
µ
1
10
2
3
4
57
8
9
AUTO
POWER
OFF

5. Operation
5.1. Auto Power Off
The meter automatically turns off after 15 minutes of inactivity. To reset the
meter after it shuts off, turn rotary function switch to the off position and than
set the switch to the desired function. To disable Auto Power Off, turn the rotary
function switch to the off position. Press and hold the MODE button and set the
rotary function switch to the desired function except switch set to current.
Release the MODE button when the “ ” symbol on the LCD display disappears.
Auto Power Off is now disabled. Auto Power Off will be restored when the meter
is turned off and back on again.
5.2. MODE Button
Used to select AC or DC voltage, Hz or % Duty Cycle, Ohms, Diode Test,
Continuity or Capacitance, and °F and °C.
5.3. MAX MIN Button
1. Momentarily press the MAX/MIN button to activate the MAX/MIN mode. The
“MAX” indicator will appear on the LCD display. The meter will display and
hold the maximum reading and will update when a higher “max” occurs.
2. Momentarily press the MAX/MIN button to view the lowest reading. The
“MIN” indicator meter will appear on the LCD display. The meter will display
and hold the minimum reading and will update when a lower “min” occurs.
3. Press and hold the MAX/MIN button to end MAX/MIN and return to normal
operation.
NOTE: The meter does not auto range when the MAX/MIN mode is active. The
display will read “OL” if the range is exceeded. MAX/MIN does not work on
Frequency, Duty Cycle, Diode Test, Continuity and Capacitance.
5.4. Flashlight Button
Press the button to turn the flashlight on and off.
5.5. HOLD/Backlight Button
To freeze the reading on the display, momentarily press the HOLD button.
“HOLD” will appear on the LCD display while the reading is being held.
Momentarily press the HOLD button again to return to normal oper ation.
The backlight illuminates the LCD display when the ambient light is too low to
view the displayed readings. To turn on, press and hold the HOLD button until
the backlight turns on. To turn off, press and hold the HOLD button again until
the backlight turns off.
7

8
5.6. AC/DC Voltage Measurements
1. Set the rotatory function switch to the V ~
position.
2. Press the MODE button to select AC or DC voltage.
The AC “ ” or DC “ ” symbol will appear on the ~
LCD display.
3. Insert the black test lead into the COM input jack
and the red test lead into the V input jack.
4. Touch the test lead probes to the circuit under test. If
measuring DC voltage, touch the red test lead to the
positive side of the circuit and the black test lead to
the negative side of the circuit.
Observe all safety precautions when working on live circuits.
!
WARNING:
5.7. Frequency And % Duty Cycle Measurements
1. Set the rotary function switch to the position. HZ %
2. Press the button to select frequency or MODE %
duty cycle. The “ ” or “ ” symbol will appear on Hz %
the LCD display.
3. Insert the black test lead into the input jack COM
and the red test lead into the input jack.V
4. Touch the test lead probes to the circuit under test.
5. Read the frequency or % duty cycle on the LCD
display.
5.8. AC Current Measurements
1. Set the rotary function switch to the 10A~ position.
2. Insert the black test lead into the COM input jack
and the red test lead into the 10A input jack.
3. Remove power from the circuit under test, then open
up the circuit at the point where you wish to
measure current.
4. Touch the test lead probes in series with the circuit
being measured.
5. Apply power to the circuit.
6. Read the current on the LCD display.
Observe all safety precautions when working on live voltages.
Do not measure frequency or duty cycle on circuits that exceed
600V.
!
WARNING:
Observe all safety precautions when working on live circuits. Do
not measure current on circuits that exceed 250V. Measurements
in the 10A range should be limited to 30 seconds maximum every
15 minutes. Max voltage 600V.
!
WARNING:

5.9. DC Current Measurements
1. Set the rotary function switch to the 10A position.
2. Insert the black test lead into the COM input jack
and the red test lead into the 10A input jack.
3. Remove power from the circuit under test, then open
up the circuit at the point where you wish to measure
current.
4. Touch the test lead probes in series with the circuit
being measured.
5. Apply power to the circuit.
6. Read the current on the LCD display.
Observe all safety precautions when working on live circuits. Do
not measure current on circuits that exceed 250V. Measurements
in the 10A range should be limited to 30 seconds maximum every
15 minutes. max voltage 600V.
!
WARNING:
9
5.10. Resistance Measurements
1. Set the rotary function switch to the Ω position.
2. Press the MODE button until the “Ω” symbol appears
on the LCD display.
3. Insert the black test lead into the COM input jack
and the red test lead into the Ω input jack.
4. Touch the test lead probes to the component under
test. If the component is installed in a circuit, it is
best to disconnect one side before testing to
eliminate interference with other devices.
5. Read the resistance in on the LCD Display.
Never test resistance on a live circuit.
!
WARNING:
5.11. Diode Test
1. Set the rotary function switch to the Ω
position.
2. Press the MODE button until the “ ” symbol
appears on the LCD display.
3. Insert the black test lead into the COM input jack
and the red test lead into the Ω input jack.
4. Touch the test lead probes to the diode under test.
5. Forward voltage will indicate 0.4 to 0.7 on the
display. Reverse voltage will indicate “ ”. Shorted OL
devices will indicate near 0 and an open device will
indicate “ ” in both polarities.OL
RED
PROBE
BLACK
PROBE
FORWARD TEST
RED
PROBE
BLACK
PROBE
REVERSE TEST
Never test diodes in a live circuit.
!
WARNING:

5.12. Continuity
1. Set the rotary function switch to the Ω position.
2. Press the MODE button until the “ ” symbol
appears on the LCD display.
3. Insert the black test lead into the COM input jack and
the red test lead into the Ω input jack.
4. Touch the test lead probes to the device or wire under
test.
5. A beeper will sound if the resistance is approximately
40Ω or less and the resistance value will be shown on
the LCD display.
Never test continuity on a live circuit.
!
WARNING:
10
5.13. Capacitance Measurements
1. Set the rotary function switch to the Ω position.
2. Press the button until the " " symbol MODE nF
appears on the LCD display.
3. Insert the black test lead into the input jack COM
and the red test lead into the input jack. Ω
4. Touch the test lead probes to the capacitor under
test.
5. Read the capacitance value on the LCD display. It
may take up to a minute to get a stable reading on
large capacitors.
1. Set the rotary function switch to the position. °F °C
2. Press the button to select readings in or . MODE °F °C
3. Connect the Temperature Probe to the Banana Plug
Adapter. Note the and markings on the adapter. – +
Connect the adapter to the meter, making sure the –
side goes into the input jack and the side goes COM +
into the input jack. °F °C
4. Touch the tip of the Temperature Probe to the object
being measured. Keep the probe touching the object
until the reading stabilizes (about 30 sec).
5. Read the temperature on the LCD display.
5.14. Temperature Measurements
Safety discharge capacitors before taking capacitance
measurements.
!
WARNING:
Do not touch temperature probe to live circuit.
!
WARNING:

1. Lift up the tilt stand.
2. Loosen the two Phillips screws on the battery/fuse cover.
3. Remove the battery/fuse cover.
4. Replace the batteries with 3 x AAA 1.5V batteries.
5. Observe proper polarity as shown inside battery compartment.
6. Install the battery cover and tighten the screws
5.15. Battery Replacement
To avoid electric shock, remove the test leads from the meter
before removing the battery/fuse cover.
!
WARNING:
11
1. Lift up the tilt stand.
2. Loosen the two Phillips screws on the battery/fuse cover.
3. Remove the battery/fuse cover.
4. Gently remove fuse and install new fuse into the holder.
5. Always use a UL recognized fuse of the proper size and value: 10A/600V
(5 x 20mm) fast blow.
6. Install the battery cover and tighten the screws.
This Multimeter is designed to provide years of dependable service, if the
following care instructions are performed:
5.16. Fuse Replacement
To avoid electric shock, remove the test leads from the meter
before removing the battery/fuse cover.
!
WARNING:
To avoid electric shock, do not operate meter until the battery/
fuse cover is securely fastened to the meter.
!
WARNING:
6. Maintenance
1. KEEP THE METER DRY. If it gets wet, wipe it off.
2. USE AND STORE THE METER IN NORMAL TEMPERATURES. Temperature
extremes can shorten the life of the electronic parts and distort or melt
plastic parts.
3. HANDLE THE METER GENTLY AND CAREFULLY. Dropping it can damage
the electronic parts or the case.
4. KEEP THE METER CLEAN. Wipe the case occasional ly with a damp cloth.
DO NOT use chemicals, cleaning solvents, or detergents.
5. USE ONLY FRESH BATTERIES OF THE RECOMMENDED SIZE AND TYPE.
Remove old or weak batteries so they do not leak and damage the unit.
6. IF THE METER IS TO BE STORED FOR A LONG PERIOD OF TIME, the
batteries should be removed to prevent damage to the unit.

12
7. General Specifications
Insulation
Enclosure
Diode Test
Continuity Test
Low Battery Indication
Display
Over Range Indication
Polarity
Measurement Rate
Auto Power Off
Input Impedance
AC Response
AC Bandwidth
Batteries
Fuse
Operating Environment
Storage Environment
Operating Altitude
Dimensions / Weight
Safety
Double Molded, IP67 waterproof and dust-proof
Test current 0.3mA typical, open circuit voltage
2.8V DC typical
Audible signal if the resistance is approx. 50Ω or less
Minus symbol “-“ is displayed for negative polarity
0°C to 40°C (32°F to 104°F), <80% relative humidity
-20°C to 60°C (-4°F to 140°F) <80% relative humidity
147 x 68 x 50mm / 318g
Complies with IEC 61010-1 v.3 for measurement
Category lll 600V, Pollution Degree 2
Class 2, Double insulation
“ ” is displayed
4000 count LCD display
“OL: is displayed
2 readings per second, nominal
After approx. 15 minutes of inactivity
7.8MΩ AC/DC voltage
Average responding
50 to 60Hz
Three “AAA” 1.5V batteries
10A/600V (5 x 20mm) fast blow
2000 meters
+ -

8. Specifications
Accuracy is given at 18°C to 28°C (65°F to 83°F), less than 70% relative humidity
400.0V 0.1V
600V 1V
Range
4.000V
40.00V
Accuracy ±(% of reading+digits)
±(1.5% + 10 digits)
Function
AC Voltage
Input Protection: 600V DC or 600V AC RMS
AC Response: 50 to 60Hz
Resolution
1mV
10mV
40.00V 100mV
400.0V
±(1.2% + 5 digits)
0.1V
Range
400.0mV
4.000V
Accuracy ±(% of reading+digits)
±(0.8% + 8 digits)
±(1.2% + 2 digits)
Function
DC Voltage
Input Protection: 600V DC or 600V AC RMS
Resolution
1mV
10mV
600V 1V
Range
4.000A
10.00A
Accuracy ±(% of reading+digits)
±(3.0% + 5 digits)
Function
AC Current
Overload Protection: 10A/600V Fuse
AC Response: 50 to 60Hz
Resolution
1mA
10mA
Range
4.000A
10.00A
Accuracy ±(% of reading+digits)
±(3.0% + 5 digits)
Function
DC Current
Overload Protection: 10A/600V Fuse
Resolution
1mA
10mA
999.9Hz
±(1.2% + 3 digits)
0.1Hz
9.999kHz 1Hz
Range
9.999Hz
99.99Hz
Accuracy ±(% of reading+digits)
±(1.5% + 5 digits)
Function
Frequency
Input Protection: 250V AC RMS or 250V DC
Sensitivity: >0.5V RMS <1MHz
>3V RMS >1MHz
Resolution
0.001Hz
0.01Hz
99.99kHz 10Hz
999.9kHz
±(1.5% + 4 digits)
100Hz
9.999MHz 1kHz
13

40.00kΩ10Ω
400.0kΩ100Ω
Range
400.0Ω
4.000kΩ
Accuracy ±(% of reading+digits)
±(1.2% + 5 digits)
Function
Resistance
Input Protection: 250V AC RMS or 250V DC
Resolution
0.1Ω
1Ω
4.000MΩ±(2.0% + 20 digits)
1kΩ
40.00MΩ±(5.0% + 20 digits)
10kΩ
±(5.0% + 20 digits)
7
4.000µF 0.001µF
40.00µF
±(2.0% + 20 digits)
0.01µF
Range
40.00nF
400.0nF
Accuracy ±(% of reading+digits)
±(1.2% + 5 digits)
Function
Capacitance
Input Protection: 600V AC RMS or 600V DC
Pulse Width: 100µs - 100ms
Frequency Range: 5Hz to 150kHz
Sensitivity: >8V RMS
Resolution
10pF
100pF
400.0µF 0.1µF
4000mF 1µF
Input Protection: 250V AC RMS or 250V DC
7
Range
-20 to 760°C
-4 to 1400°F
Accuracy ±(% of reading+digits)
±(3% + 5°C)
Function
Temperature
Resolution
1°C
1°F ±(3% + 9°F)
14
Range
0.1% to 99.9%
Accuracy ±(% of reading+digits)
±(1.2% + 2 digits)
Function
Duty Cycle
Resolution
0.1%
Input Protection: 600V AC RMS or 600V DC
Pulse Width: 100µs - 100ms
Frequency Range: 5Hz to 150kHz
Sensivity: >8V

15

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South Africa Australia