Mastech MS2140A User manual

MS2140A
Dual display digital
clamp meter
CAT ll 1000V
A~
Hz
MS2140A
T-RMS
Inrush
TEMP
Hz
μA
Ω
A
V
REL
ZERO
FUNC
INRUSH
HOLD
RANGE
MIN
MAX
COM Temp μAHz
ΩV
RELINP MAX MIN °C%
kHz
°F
µmVA
nµmF
MkΩHz
AUTO
K-T
NCV
MAX
1000V
Press 2Sec
CAT lll 600V
600A
TRMS
AutoRange
CUS
int erte k
308 0912

CONTENTS CONTENTS
1. Safety Information.............................1
1.1 Preparation..............................................1
1.2 Usage.......................................................2
1.3 .....................3 Safety symbols on the meter
1.4 Maintenance............................................4
2. ................4Features and Components
2.1 ............................................5 Components
2.2 ................................7Buttons and switches
2.3 ..................................7Display Description
3. Specification.....................................9
3.1 ..............................9General Specifications
3.2 ..........................10Technical Specifications
4. .............................16Operations Guide
4.1 ...........................................16Display Hold
4.2 ..............................16Manual Measurement
4.3 ........................16Backlight and Clamp light
4.4 ................17 Maximum/Minimum recording
4.5 ..................................17Function switching
4.6 ...............................................17ZERO/REL
5. Maintenance......................................24
5.1 ..........................24Replacing the batteries
5.2 ...........................25Test Leads Replacement
6. .......................................25Accessories
4.7 ...................................................18INRUSH
4.8 ..........................................18Auto Power Off
4.9 .............................18Measuring Preperation
4.10 .............................19Current Measurement
4.11 .............................19Voltage Measurement
4.12 ......................20Frequency and Duty Cycle
4.13 .............................................20Resistance
4.14 ..............................................21Diode Test
4.15 ...............................................21Continuity
4.16 ...........................................22Capacitance
4.17 ..................22Inrush Current Measurement
4.18 ...........................................23Temperature
4.19 ........................23μA Current Measurement
4.20 ...................23NCV Sensitivity and settings

01 02
1. Safety Information
This meter has met IEC61010-1 and IEC-61010-2-032
standards with an overvoltage category of 600V CAT III
and a pollution degree of 2. Follow safe operation
procedures to ensure the long life and safe use of this
instrument.
WARNING
1.1 Preparation
1.1.1 When using the meter, follow the following
safety rules:
-Take precautions to prevent electrical shock
-Do not misuse the instrument
1.1.2 Check the meter and accessories thoroughly
before using.
1.1.3 Check to see if the meter or any components
were damaged during shipment.
1.1.4 Inspect test leads and probes for cracks, breaks
or crazes on the insulation before using the meter.
1.1.5 Use test leads provided with the unit. If
necessary, replace test leads with identical
specifications.
1.2 Usage
1.2.1 Turn the rotary switch to the required function
and range to be measured.
1.2.2 Never use the meter to measure voltages that
might exceed 600V DC/AC above earth ground.
1.2.3 Always be careful when working with voltages
above 60V DC or 30V AC RMS. Keep fingers
behind the probe barriers while measuring.
1.2.4 The “ ” symbol next to the input lead shows
that the input voltage or current should not
exceed the specified value in order to protect the
internal circuit from damage.
1.2.5 Choose the highest range when the value to be
measured is unknown.
1.2.6 Remove test leads before switching functions on
the rotary switch.
1.2.7 Do not perform resistance, capacitance, diode
and continuity measurements on powered circuits.
1.2.8 Never connect the test leads across a voltage
source while the rotary switch is in the resistance,
diode or continuity mode. Doing so can damage
the meter.
1.2.9 Power off the circuit and discharge capacitors
before testing capacitance.
1.2.10 Do not place the meter in any environment with
high pressure, high temperature, dust, explosive
gas or vapor.
1.2.11 Stop using the meter if any failure or abnormal
function is observed.
1.2.12 Do not use meter unless battery cover is in place
a secured.
TO REDUCE THE RISK OF FIRE, ELECTRICAL
SHOCK, PRODUCT DAMAGE OR PERSONAL
INJURY, PLEASE FOLLOW THE SAFETY
INSTRUCTIONS DESCRIBED IN THE USER
MANUAL. READ THE USER MANUALS
BEFORE USING THE METER.

03 04
1.3 Safety symbols on the meter
Important safety information; please refer to
user manual
High voltage
Compliance with requirements for double
insulation
Refers to the impulse withstand voltage
protection level in accordance with IEC-61010-1
standard overvoltage (installation) category III,
pollution degree 2.
Meter complies with European Community
(CE) standards
Earth ground
1.4.1 To avoid electric shock or personal injury, repairs
or servicing not covered in this manual should be
performed only by qualified personnel.
1.4.2 Remove test leads before opening battery cover
1.4.3 To avoid incorrect readings causing electric
shock or personal injury, when low battery
symbol “ ”appears replace batteries immediately.
1.4.4 The meter can be cleaned with a soft cloth to
remove any oil, grease or grime. Do not use
liquid solvent or detergent.
1.4.5 When the instrument is not in use, turn rotary
switch to “OFF”
1.4.6 If the instrument is not to be used for an extended
period of time, remove the batteries to prevent
damage to the instrument.
1.4 Maintenance
2. Features and Components
The CM660 is a portable, hand-held yet professional
meter that features an LCD with backlight, overload
protection and low battery indicator. These meters are
easy to use with one hand, suitable for professional
users or amateurs, and ideal for school or home use.
CAT III
1.2.13 Avoid direct sunlight, exposing batteries to
humidity, any strong magnetic field, or high
temperatures to ensure the extended life of
the meter.
-Auto and manual range
-Reading Hold function
-Max measurement
-Min measurement
-Frequency in clamp mode
-Auto power off
-Relative measurement
- Inrush measurement

05 06
(1) Non-Contact Voltage detection sensor
(2)NCV indicator
(3)Work light
(4)Rotary Switch
(5)Function buttons
(6)Input sockets
(7)Clamp trigger
(8)Clamp: for current measurement
2.1 Components
1
2
3
4
5
6
7
8
CAT ll 1000V
A~
Hz
MS2140A
T-RMS
Inrush
TEMP
Hz
μA
Ω
A
V
REL
ZERO
FUNC
INRUSH
HOLD
RANGE
MIN
MAX
COM Temp μAHz
ΩV
RELINP MAX MIN °C%
kHz
°F
µmVA
nµmF
MkΩHz
AUTO
K-T
NCV
MAX
1000V
Press 2Sec
CAT lll 600V
600A
TRMS
AutoRange
CUS
int erte k
308 0912

AC/DC
Diode, Continuity
Auto-range
Maximum/Minimum display
Inrush
Relative measurement mode
Auto Power Off
Display Hold
Percentage (Duty Cycle)
millivolts, volts, amps
nanofarad, microfarad, millifarad
Non-contact voltage
ohms, kiliohms, megaohms
hertz, kilohertz, megahertz
K-type thermocouple measurement
K-T
Hz, kHz, MHZ
nF,μF,mF
mV,V,A
%
AUTO
MAX /MIN
INR
REL
H
celcius, fahrenheit
°C,°F
Low Battery
NCV
Ω,kΩ,MΩ
07 08
2.3 Display Description
2.2 Buttons and switches
/RANGE button: backlight/switch ranges in
manual mode
FUNC button: switch measurement functions
HOLD button: hold reading on screen
REL/ZERO button: relative reading/DC zero offset
INRUSH button: measure Inrush current
MAX/MIN button: switch between max/min readings
Rotary Switch: switch between measurements
INPUT jack: voltage, current, resistance, capacitance,
diode, continuity, frequency, duty cycle,
temperature input terminal
COM jack: common input terminal
RELINP MAX MIN °C%
kHz
°F
µmVA
nµmF
MkΩHz
AUTO
K-T
NCV

09 10
3. Specifications
• Manual and Auto Mode
Power Overload Protection
Maximum Voltage Between Circuit and Ground:
1000V DC or 1000V AC
Maximum Working Height: 2000m
Display: LCD
Maximum Display Number: 5999
Auto Polarity Indication, '-'Indicates Negative
Overload Indication: '0L' Or '-0L'
Sampling Frequency: 4 Times / Sec
Units Display: Display Functions and Units.
Auto Power Off: 20 Minutes
Input Power : 4.5V DC
Battery Type: AAA
Low Battery Indication: LCD Display “ ”
Temperature: Less Than 0.1 X Specified Accuracy/°C
Working Environment Temperature: 18°C ~28°C
Storage Temperature:-10°C ~50°C
Size 238×92×50mm
Weight: ~420g (Including battery)
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
The Meter should be calibrated annually between
18°C ~ 28°C and a relative humidity less than 75%.
3.1 General Specifications
3.2 Technical Specifications
3.2.1 True RMS Characteristics
3.2.1.1 For non-sinusoidal signal measurements,
true RMS is a more accurate method of
measurement over the averaging method.
3.2.2 AC Current
Accuracy
Resolution
Range
±(1.8% of reading + 10 digits)
60A
600A
0.01A
0.1A
- Maximum input current: 600A AC
- Frequency range: 50 ~ 60Hz
3.2.3 DC Current
Accuracy
Resolution
Range
±(3% of reading + 10 digits)
60A
600A
0.01A
0.1A
-Maximum input current :600A DC
3.2.4 Inrush Current
Integration time: 100ms; Measuring range: 10 ~ 600A；
Accuracy
Resolution
Range
60A
600A
0.01A
0.1A
< 60A for reference only
±(10% reading + 60 digits)

11 12
3.2.5 DC Voltage
Accuracy
Resolution
Range
±(0.5% of reading + 3 digits)
0.1V
0.01V
0.001V
0.1mV600mV
6V
60V
600V
-Input impedance: 10MΩ.
-Maximum input voltage:600V AC (RMS) or 600V DC
-600mV range: only by pressing RANGE button.
3.2.6 AC Voltage
Accuracy
Resolution
Range
±(0.8% of reading + 3 digits)
0.1V
0.01V
0.001V
0.1mV600mV
6V
60V
600V
Note:
At small voltage ranges, unsteady readings will appear
before the test leads make contact with the circuit.
This is normal since the Meter is highly sensitive.
When the test leads are connected to the circuit, the
true reading will be shown.
Note:
At small voltage ranges, unsteady readings will appear
before the test leads make contact with the circuit.
This is normal since the Meter is highly sensitive.
When the test leads are connected to the circuit, the
true reading will be shown.
-Input impedance:10MΩ.
-Maximum input voltage: 600V AC (RMS) or 600V DC
-Frequency range:50 ~ 60Hz
-600mV range: only by pressing RANGE button.
3.2.7 Frequency
Accuracy
Resolution
Range
0.01Hz
60Hz
-Measuring range: 10Hz ~ 1kHz
-Input range≥1A AC (RMS) (Input current should
increase as circuit frequency increases.)
3.2.7.1 Frequency through Clamp Measuring (A Mode)
±(1.5% of reading + 5 digits)
600Hz 0.1Hz
3.2.7.2 Frequency through “V” mode:
Accuracy
Resolution
Range
0.01Hz60Hz
±(1.5% of reading + 5 digits)
0.1Hz
1Hz
-Measuring range:10Hz ~ 1kHz
-Input range≥20mA AC(RMS) (Input current should
increase as circuit frequency increases.)）
6kHz 1Hz
10Hz60kHz
600Hz
6kHz
1V
1000V
1V
1000V

13 14
3.2.7.3 Frequency Through “HZ” Mode:
- Input signal: VPP 3V square wave; Overload
Protection: 250V DC or AC (RMS)
3.2.8 Duty Cycle
Accuracy
Resolution
Range
5-95% ±3.0% 0.1%
Accuracy
Resolution
Range
0.01Hz
60Hz
±(0.3% of reading + 5 digits)
0.1Hz
1Hz
0.01kHz
60kHz
600Hz
6kHz
0.1kHZ
1kHZ
0.01MHZ60MHZ
600kHZ
6MHZ
Accuracy
Resolution
Range
±(0.8% of reading + 3 digits)
3.2.9 Resistance
±(1.2% of reading + 3 digits)
60MΩ
600Ω
6kΩ
60kΩ
600kΩ
6MΩ
0.001kΩ
0.1Ω
0.01kΩ
0.1kΩ
0.001MΩ
0.1MΩ
- Overload protection: 250V DC or AC (RMS)
When measuring frequencies > 60KHz, duty cycle
measurement range is 10 to 90%
3.2.11 Capacitance
- Overload protection: 250V DC or AC (RMS)
3.2.12 Diode
Accuracy
Resolution
Range
- Forward DC current: about 1mA
- Open circuit voltage: about 2.8V
- Overload protection: 250V DC or AC (RMS)
0.001V Displays approximate
forward voltage.
Accuracy
Resolution
Range
3.2.10 Continuity
- Overload protection: 250V DC or AC (RMS)
- Open circuit voltage: about 3V
0.1Ω
The Meter will beep if
measurement is less
than 50
Accuracy
Resolution
Range
±(4.0% of reading + 5 digits)
6nF
60nF
600nF
6µF
60µF
600µF
6mF
60mF
0.001nF
0.01nF
0.1nF
0.001µF
0.01µF
0.1µF
0.001mF
0.01mF
±(5.0% of reading + 5 digits)

3.2.13 Temperature
Note: The accuracy does not include K-type
thermocouple error.
16
15
During measuring, press the “HOLD” button once to
hold the reading, press again to release hold.
4. Operations Guide
4.1 Display Hold
4.2 Manual Measurement
When using the rotary switch to switch between current,
voltage, capacitance and frequency mode, the default
range type is Auto. Press “RANGE” button to enter
manual mode. Each press increases the measuring
range and will return to auto-range after maximum has
been reached.
Manual Measurement Mode is disabled when
performing frequency measurement.
Note:
4.3 Backlight and Clamp light
1) Press the “ /RANGE”button for 2 seconds to turn
on the display backlight; the backlight will stay on
for 20 seconds before it is automatically turned off.
2)When the backlight is on, press the “ /RANGE”for
2 seconds to turn off the backlight.
3) In current mode, turning on the backlight will also
trigger the clamp light
Note: Backlight/clamp light uses and LED; even
though the light will auto off after 20 seconds,
use only when needed to conserve power.
Accuracy
Resolution
Range
0.1°C/
0.2°F
±1.0% of reading + 0.8°C
(±1.0% of reading + 0.8°F)
-10°C~500°C
(-14°F to 932°F)
-40°C~ -10°C
(-40°F to -14°F)
±5.0% of reading + 1.5°C
(±5.0% of reading + 3.3°F)
3.2.14 AC µA Current
Accuracy
Resolution
Range
200.0µA 0.1µA
2000µA ±(1.0% of reading + 5 digits) 1µA
-Frequency range: 50 ~ 60Hz;
- Overload protection: 250V DC or AC (RMS)
3.2.15 DC µA Current
Accuracy
Resolution
Range
200.0µA 0.1µA
2000µA ±(1.0% of range + 5 digits) 1µA
- Overload protection: 250V DC or AC (RMS)

17 18
4.4 Maximum/Minimum recording
1) Press “MAX/MIN” button once to display the
maximum measurement and press “MAX/MIN”
button again to display the minimum, press
“MAX/MIN” button a third time to return to
normal mode.
2) In Max/Min mode, measurement is saved
automatically.
3) Max/Min values are displayed on the secondary
display while the current measured value is
displayed on the main display.
Note:
1) The Meter is set to manual mode when using
Max/Min measurement.
1) When rotary switch is on Resistance, Diode,
capacitance, and continuity mode, press “FUNC”
button to switch between those four.
2) When rotary switch is on Voltage and Current mode,
press “FUNC” button to switch between AC and DC.
4.5 Function switching
1) Press “ZERO/REL” button to enter relative
measurement mode. When in this mode, the current
reading will be stored and shown on the secondary
display while the main display with show the
difference of current reading and stored reading.
REL (Output) = (current reading) – (reading when
button pressed).
2) “REL” can only perform under manual mode.
4.6 ZERO/REL
4.7 INRUSH
When in AC Current measurement mode, press the
“INRUSH” button to enter surge current measurement
mode. Press button again to return to normal mode.
4.8 Auto Power Off
1) When not in use, the meter will automatically turn
off after 20 minutes.
2) After Auto Off, press any button to bring power
back on.
3) To disable Auto Off, hold “ZERO/REL” when turning
on the Meter.
4) When auto power off is on, symbol appears on,
symbol appears on screen. screen.When disabled,
symbol does not appear.
4.9 Measuring Preperation
1) Turn on the meter by turning the rotary switch.
If battery voltage is low ( 3.6V), “ ” appears;
replace the battery.
2) “ ”indicates input voltage or current should not
exceed the indicated value; this is to protect the
meter from damage.
3) Turn the rotary switch to the proper position.
4) When connecting to the circuit, connect COM input
first before connecting to power. Remove the power
lead first when disconnecting from the circuit.

19 20
4.10 Current Measurement
1) For AC current move rotary switch to A~ position;
for DC current move rotary switch to A position.
2) Open the clamp head by pressing the trigger and
inserting the conductor to be measured.
3) When measuring AC current, the main display
shows the measured current value while the
secondary display shows the frequency of the
measured current
Note:
1) Measuring two or more wires together will cause
false readings.
2) The wire being measured should be centered within
the clamp.
3) “ ”indicates the maximum input AC/DC current is
600 A.
4) For higher accuracy, when measuring DC current
if Display shows non zero, press “ZERO/REL”
button to reset the reading to zero.
Note:
1) When measuring low voltage source, the meter
When measuring low voltage sources, the reading
will fluctuate on the display when the test leads are
not connected to the circuit. This is normal due to
the high sensitivity of the Meter. The Meter will
display correct reading once the leads are
connected to the circuit.
4.12 Frequency and Duty Cycle
1) Insert the black test leads into “COM” input and red
test lead into “INPUT” input
2) Turn rotary switch to “Hz” position.
3) Connect test leads to the voltage source or
between loads.
Note:
Frequency range is 10Hz ~ 60MHz. For frequencies
below 10Hz, display will show “00.0.” For frequencies
about 60kHz, duty cycle measurement accuracy is
not guaranteed.
4.11 Voltage Measurement
1) Insert the black test leads into “COM” input and red
test lead into “INPUT” input, choose proper range.
2) Move rotary switch to V position. AC voltage is
default measurement. Press “FUNC” to switch to
DC voltage.
3) For mV measurement, press “RANGE” button until
in mV range.
4) Connect test leads to voltage source or load.
5) Voltage measurement will be shown on main display.
4.13 Resistance
1) Insert the black test leads into “COM” input and red
test lead into “INPUT” input
2) Turn rotary switch to “ ” position for resistance
measurement.
3) Connect the test leads across the circuit or resistors
and read value on LCD.

21 22
Note:
1) When the circuit is an open circuit, the Meter displays
“OL” for overload.
2) For measurements above 1MΩ, the meter will take a
few seconds to stabilize the reading; this is normal
for high resistance measurements.
4.14 Diode Test
1) Insert the black test leads into “COM” input and red
test lead into “INPUT” input
2) Turn rotary switch to “ ”position and push “FUNC”
twice for diode test.
3) Connect the black lead to the cathode (-) and the
red lead to the anode (+) and read the value from
the LCD.
1) The meter displays the forward biased value.
2) If the diode is connected backward or is an open
circuit, the Meter will display “OL”.
Note:
Note:
The Meter displays “OL” if the circuit is open or
resistance is larger than 600Ω.
4.16 Capacitance
1) Insert the black lead into “COM” input and the red
lead into “INPUT” input.
2) Turn the rotary switch to “ ” position and push
“FUNC” three times for capacitance .
3) Place leads at the terminals of the capacitor after it is
fully discharged.
4) Read the measurement from the display.
4.17 Inrush Current Measurement
1) Turn rotary switch to “A” position
2) Push “INRUSH”button to enter inrush current mode.
3) Open the clamp head by pressing the trigger and
inserting the conductor to be measured.
4) Power on the circuit being tested
5) Largest value will be held on main display
4.15 Continuity
1) Insert the black test leads into “COM” input and red
test lead into “INPUT” input
2) Turn rotary switch to “ ” position and push “FUNC”
once for continuity test.
3) Connect leads to the circuit terminals.
4) The meter will beep if the reading is below 50Ω.
5) Screen will show resistance value
Note:：
1) Measuring two or more wires together will cause false
readings.
2) The wire being measured should be centered within
the clamp.
3) The Meter displays “OL” if the circuit is overloaded.
Choose a larger range if possible.
4) Choose the largest range if the range of the circuit is
unknown.

23 24
1) Turn rotary switch to “TEMP” position.
2) Insert K-type thermocouple into the multi-function
socket with the “+” end in “INPUT” input and “-“ into
“COM” input.
3) Temperature reading will show on main display.
4.18 Temperature
4.19 μA Current Measurement
4.20 NCV Sensitivity and settings
1) Hold “FUNC” when you turn on the meter and the
following display will show up on the LCD:
2) Push the “RANGE” button to adjust the NCV
sensitivity from 0-4. '4' is the highest sensitivity
where '0' will turn off the NCV functionality.
3) Push the “HOLD” button to save the selected
sensitivity and return to normal meter operation.
4) With the NCV function active (sensitivity between
1-4), if the sensor at the top of the clamp gets close
to a live conductor (AC voltage >90V) the NVC
indicator will flash and buzzer will sound.
Note:
1) Even though there is no indication, voltage may still
exist. Do not rely solely on NCV detector to determine
the presence of voltage in a wire. The measurement
may be affected by the design of the outlet, type of
insulation and other external factors.
2) The voltage sensing indicator may turn on when a
voltage is fed to the meter.
3) Other external interference (ex. Flashlight, motor)
may trigger the NCV sensor.
1) Insert the black lead into “COM” input and the red
lead into “INPUT” input.
2) Turn the rotary switch to μA position.
3) Push “FUNC” to switch between AC/DC current
4) Connect test leads to circuit.
5) Current measurement will be shown on main display.
NCV 5. Maintenance
5.1 Replacing the batteries
TO AVOID ELECTRICAL SHOCK, PRODUCT
DAMAGE OR PERSONAL INJURY, REMOVE
TEST LEADS BEFORE OPENNING BATTERY
COVER.
WARNING

25
1) If “ ”symbol appears, this indicated batteries
should be replaced.
2) Unscrew the instrument's battery cover and remove it
3) Replace batteries
4) Replace the battery cover and tighten screws
Note:
Be sure to note the battery polarity when replacing.
5.2 Test Leads Replacement
REPLACE THE TEST LEADS WITH IDENTICAL
OR COMPATIBLE LEADS. LEAD SPEC:
1000V 10A.
WARNING
Replace new leads if the current leads are worn.
6. Accessories
1) Test Leads: Rating:1000V 10A 1 pair
2) User’s Manual 1 pc
3) Batteries: AAA Battery 3 pc
4) K-type thermocouple 1 pc
5) Multi-function socket 1 pc
00-05-3465