Major tech MT 770 User manual

MT 770
AC CLAMP METER
INSTRUCTION MANUAL
© 2004, MAJOR TECH (PTY) LTD. All rights reserved

1. Measuring Limits ........................... 1
2. Safety Warnings ............................ 2
3. Features ......................................... 4
4. Instrument Layout ......................... 5
5. Specifications ................................ 5
6. AC Current Measurement ............. 7
7. DC Voltage Measurement ............. 8
8. AC Voltage Measurement ............. 9
9. Resistance Measurement ............. 10
10. Capacitance Measurement ........... 11
11. Frequency Measurement .............. 12
12. Duty Cycle Measurement ............. 13
13. Temperature Measurement .......... 14
14. Diode Test ...................................... 15
15. Continuity Testing ......................... 16
16. Other Functions ............................ 17
17. Battery Replacement .................... 18
18. Standard Accessories ................... 18
MEASURING LIMITS
AC Amperes : 0.1A to 1000A
DC Voltage : 0.1mV to 600V
AC Voltage : 0.1mV to 600V
Resistance : 0.1Ω to 40MΩ
Capacitance : 0.01 nF to 100µF
Frequency : 0.001 Hz to 10MHz
Duty Cycle : 0.5% to 99.0%
Temperature : -20 ºC to 1000 ºC
- 4 ºF to 1832 ºF
1
CONTENTS

2
1. SAFETY INFORMATION
This manual contains information that must be
followed for operating the meter safely and
maintaining the meter in a safe operating
condition. If the meter is not used in a manner
specified in this manual, the protection provided
by the meter may be impaired
The Model MT770 has been designed and
complies with IEC 61010-1 and EN 61010-1
Safety Requirements for Electronic Measuring
Apparatus.
WARNING
! Read through the operating instructions
throughly and understand the instructions
before operating the meter.
! Keep the manual at hand so as to enable
quick reference when necessary
! Ensure that the use of the meter is in its
intended applications and follow
measurement procedures described in this
manual.
! Follow all safety and operating instructions to
ensure maximum personal safety during the
use and operation of the meter.
! Failure to follow the above instructions may
cause injury, instrument damage and/or
damage to equipment under test.
!The symbol indicated on the meter means that
the user must refer to related parts in the
manual for safe operation of the meter. Be
sure to carefully read the instructions following
each symbol in this manual.
DANGER is reserved for conditions and
actions that are likely to cause serious or fatal
injury
WARNING is reserved for conditions and
actions that are likely to cause serious or fatal
injury
CAUTION is reserved for conditions and
actions that are likely to cause minor injury or
!
!
!
!

DANGER
! Never use the meter to measure voltages on a
circuit above the maximum allowable input
value on any function.
! Do not exceed the maximum allowable input
of any measurement range.
! Never touch exposed wiring, connections or
any live circuit when attempting to take
measurements.
! Do not attempt to make measurements in
flammable gaseous areas, fumes, vapor or
dust. The use of the instrument in these areas
may cause sparking , which can lead to an
explosion.
! Do not attempt to use the instrument if its
surface or your hand is wet
! Never open the battery compartment cover
when making measurements.
WARNING
! Always inspect the meter and test leads for
any signs of damage or abnormality before
use. If the meter or its accessories have any
structural defects such as broken test leads,
cracked cases, exposed metal parts or the
display is not reading, do not attempt to make
measurements.
! Do not turn the function switch whilst test
leads are connected to the meter.
! Do not install substitute parts or make
modifications to the meter. Return the meter
to your distributor for repair or re-calibration.
! Ensure the meter is switch off before opening
the battery cover when replacing the battery.
! Never replace a battery if the surface of the
meter is wet or moist.
3
!!
!

CAUTION
! Before making measurements ensure that the
function selector switch is set on the
appropriate range position.
! Always make sure that the plug of each test
lead is inserted fully into the appropriate
terminal of the meter.
! Ensure that the function selector switch is set
to the “OFF” position after use. When the
meter will not be in use for a long period of
time, place it in storage after removing the
battery.
! Do not expose the meter to direct sunlight,
extreme temperatures or moisture.
! Do not use abrasives or solvents on the meter.
To clean it use a damp cloth and mild
detergent only.
Qualified and trained service technicians should
only perform calibration and repair of the meter.
2. FEATURES
! Large 4000 count LCD display with bright
white LED backlight.
! Wide measuring range from 0.01A AC up to
1000A AC
! Measures AC and DC Voltage up to 600 volts
! Measures resistance from 0.01Ω up to 40MΩ.
! Capacitance measurements up to 100µF
! Temperature measurement from -20ºC to
+1000ºC and -4ºF to +1832ºF.
! Designed to the international safety standard
IEC61010 CAT lll 600V / CAT ll 1000V,
Pollution degree 2.
! Auto Power Off after approximately 30
minutes to conserve battery life.
! Continuity Buzzer and Diode Test
! Frequency measurement up to 10MHz, with
Duty Cycle testing
! Data Hold switch used to freeze reading on
display
4
!!

3. INSTRUMENT LAYOUT
Transformer
Jaws
Function
Switch
Jaw Trigger
Data Hold
& Backlight
Switch
Mode Switch
Display
COM
Terminal
Volt, Resistance,
Frequency,
Temperature
Terminal
Frequency,
Duty Cycle
Switch
Range Selector
Switch for Volts
and Resistance
Clamp Size
Diode Test
Continuity Check
Low Battery Indication
Overrange Indication
Measurements Rate
Input Impedance
Display
AC Current
AC Voltage Bandwidth
Operating Temperature
Storage Temperature
Relative Humidity
Over Voltage
Battery
Auto Power Off
Dimensions
Weight
30mm Opening Approx
Test Current of 0.3mA typical;
Open circuit voltage 1.5V DC
Threshold <100Ω; Test current <1mA
“ “ is displayed
“OL” is displayed
2 per second, nominal
7.8MΩ (VDC and VAC)
4000 count LCD
50/60Hz (AAC)
50/60Hz (VAC)
-10ºC to 50ºC (-14ºF to 122ºF)
-30ºC to 60ºC (-14ºF to 140ºF)
Up to 85%
Category lll 600V
One PP3 “9V” Battery
Approx 30 minutes
229 x 80 x 49mm
303g
4. SPECIFICATIONS
+
5

4. SPECIFICATIONS
Range
AC Current
Measuring Range Resolution
40A
400A
1000A
0 ~ 40.00A
0 ~ 400.0A
0 ~ 1000A
0.01 A
0.1 A
1 A
Accuracy (% of Reading)
± (2.5% + 10 digits)
± (2.5% + 5 digits)
± (3.0% + 5 digits)
Range
DC Voltage
Measuring Range Resolution
400mV
4V
40V
400V
600V
0 ~ 400.0mV
0 ~ 4.000V
0 ~ 40.00V
0 ~ 400.0V
0 ~ 600V
0.1 mV
0.001 V
0.01 V
0.1 V
1 V
Accuracy (% of Reading)
± (0.8% + 3 digits)
± (1.5% + 3 digits)
± (2.0% + 3 digits)
Range
AC Voltage
Measuring Range Resolution
400mV
4V
40V
400V
600V
0 ~ 400.0mV
0 ~ 4.000V
0 ~ 40.00V
0 ~ 400.0V
0 ~ 600V
0.1 mV
0.001 V
0.01 V
0.1 V
1 V
Accuracy (% of Reading)
± (0.8% + 10 digits)
± (1.8% + 5 digits)
± (2.5% + 5 digits)
Range
Resistance
Measuring Range Resolution
400Ω
4kΩ
40kΩ
400kΩ
4MΩ
40MΩ
0 ~ 400.0Ω
0 ~ 4.000kΩ
0 ~ 40.00kΩ
0 ~ 400.0kΩ
0 ~ 4.000MΩ
0 ~ 40.00MΩ
0.1 Ω
1Ω
10 Ω
100 Ω
1 kΩ
10 kΩ
Accuracy (% of Reading)
± (1.0% + 4 digits)
± (1.5% + 2 digits)
± (2.5% + 3 digits)
± (3.5% + 5 digits)
Note: No Autoranging on 400mV AC Range
Range
Capacitance
Measuring Range Resolution
40nF
400nF
4µF
40µF
100µF
0 ~ 40.00nF
0 ~ 400.0nF
0 ~ 4.000µF
0 ~ 40.00µF
0 ~ 100.0µF
0.01 nF
0.01 nF
0.001 µF
0.01 µF
0.1 µF
Accuracy (% of Reading)
± (5.0% + 20 digits)
± (3.0% + 5 digits)
± (3.5% + 5 digits)
± (5.0% + 5 digits)
Range
Frequency
Measuring Range Resolution
5Hz
50Hz
500Hz
5kHz
50kHz
500kHz
5MHz
10MHz
0 ~ 5.000Hz
0 ~ 50.00Hz
0 ~ 500.0Hz
0 ~ 5.000kHz
0 ~ 50.00kHz
0 ~ 500.0kHz
0 ~ 5.000MHz
0 ~ 10.00MHz
0.001 Hz
0.01 Hz
0.1 Hz
1 Hz
10Hz
100 Hz
1 kHz
10 kHz
Accuracy (% of Reading)
± (1.5% + 5 digits)
± (1.2% + 2 digits)
Sensitivity: 10Vrms min
± (1.2% + 10 digits)
Range
Duty Cycle
Measuring Range Resolution
%0.5% ~ 99.0%
Pulse width:
100µs - 100ms
0.1 %
Accuracy (% of Reading)
± (1.2% + 2 digits)
Range
Temperature
Measuring Range Resolution
ºC
ºF
-20.0ºC ~ 400.0ºC
400ºC ~ 1000ºC
-4.0ºF ~ 400.0ºF
400ºF ~ 1832ºF
0.1 ºC
1 ºC
0.01 ºF
1 ºF
Accuracy (% of Reading)
± (3.0% + 5ºC)
± (3.0% + 7ºF)
6

5. AC CURRENT MEASUREMENT
WARNING: Ensure that the test leads are
disconnected from the meter before making
current measurements.
1. Set the function switch to or or
range position, and make sure that the
current under test does not exceed the upper
limit of the measuring range you have
selected.
2. Press the trigger to open up the transformer
jaws and clamp around the single conductor
under test.
3. Read the display.
Note: • During current measurements keep the
transformer jaws fully closed, otherwise
this will affect the accuracy of the
measurement.
• When large currents the transformer
jaws may buzz. This is not a fault and
does not affect the accuracy of the
reading.
40A
~
400A
~
1000A
~
Correct Current
Measurement
Incorrect Current
Measurement
7
!!

+
-
6. DC VOLTAGE MEASUREMENT
1. Set the function switch to range
position. The meter automatically defaults to
DC Volts.
2. Insert the red test lead into the “V Ω ºC ºF HZ”
input terminal and the black lead to the “COM”
terminal.
3. Connect the other end of the test leads to the
circuit under test.
4. Read the display. If a “-” sign is displayed, the
red lead is the negative potential.
Note: • The meter is set to default to “Auto
Range” mode.
• Pressing the button transforms
the meter into a ‘Manual Range” mode.
This means that the user will have to
depress this button to select the correct
range for the voltage being measured.
• In order to return back to the “Auto
Range” mode, hold down the
button for 3 seconds.
V
__
~
RANGE
RANGE
Battery
8

AC Supply
7. AC VOLTAGE MEASUREMENT
1. Set the function switch to range
position.
2. Press the ” button to select the AC Volt
range. The meter automatically defaults to DC
Volts.
3. Insert the red test lead into the “V Ω ºC ºF HZ”
input terminal and the black lead to the “COM”
terminal.
4. Connect the other end of the test leads to the
circuit under test. Take the reading on the
display.
Note: • The meter is set to default to “Auto
Range” mode.
• Pressing the button transforms
the meter into a ‘Manual Range” mode.
This means that the user will have to
depress this button to select the correct
range for the voltage being measured.
• In order to return back to the “Auto
Range” mode, hold down the
button for 3 seconds.
• To test Frequency on AC Voltage simple
press the button.
MODE
RANGE
RANGE
V
__
~
9
%
Hz
•