Mastech MS8221C User manual

1
DIGITAL
MULTIMETER
INSTRUCTION MANUAL

2
DIGITAL MULTIMETER
CONTENTS
CONTENTS
1. SAFETY INFORMATION ……1
1.1 PRELIMINARY ……1
1.2 DURING USE ……2
1.3 SYMBOLS ……3
1.4 MAINTENANCE ……4
2. DESCRIPTION ……5
2.1 NAMES OF COMPONENTS ……5
2.2 SWITCH, BUTTONS AND INPUT JACK
ELUCIDATION
……6
3. SPECIFICATIONS ……7
3.1 GENERAL SPECIFICATIONS ……7
3.2 ELECTRICAL SPECIFICATIONS ……8
4. OPERATING INSTRUCTION ……13
4.1 POWER-UP ……13
4.2 DATA HOLD ……13
4.3 MAXIMUM HOLD ……13
4.4 FUNCTION TRANSFORM ……13
4.5 RANGE TRANSFORM ……13
4.6 BACK LIGHT ……14
4.7 AUTO POWER OFF ……14
4.8 PREPARATION FOR MEASUREMENT ……15
4.9 MEASURING DC VOLTAGE ……15
4.10 MEASURING AC VOLTAGE ……17
4.11 MEASURING DC CURRENT ……18
4.12 DC CURRENT MEASURING (WITH
CLAMP, OPTIONAL)
……19
4.13 MEASURING AC CURRENT ……20

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DIGITAL MULTIMETER
CONTENTS
4.14 AC CURRENT MEASURING (WITH
CLAMP, OPTIONAL)
……22
4.15 MEASURING RESISTANCE ……23
4.16 MEASURING TEMPERATURE ……24
4.17 MEASURING CAPACITANCE ……25
4.18 DIODE TESTING ……26
4.19 CONTINUITY TESTING ……27
4.20 TRANSISTOR TESTING ……28
5. MAINTENANCE ……29
5.1 BATTERY REPLACEMENT ……29
5.2 FUSE REPLACEMENT ……29
5.3 TEST LEADS REPLACEMENT ……30
6. ACCESSORIES ……31

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DIGITAL MULTIMETER
SAFETY INFORMATION
1. SAFETY INFORMATION
WARNING
To ensure safe operation, and in order to exploit to the
full the functionality of the meter, please follow the
directions in this section carefully.
This multimeter has been designed according to
IEC-61010-1 concerning electronic measuring instruments
with an overvoltage category CAT ΙΙΙ 600V and pollution 2.
Follow all safety and operating instructions to ensure that the
meter is used safely and is kept in good operating condition.
With proper use and care, the digital meter will give you
years of satisfactory service.
1.1 PRELIMINARY
1.1.1 When using the meter, the user must observe all
normal safety rules concerning:
•Protection against the dangers of electrical current.
•Protection of the meter against misuse.
1.1.2 When the meter is delivered, check that it has not been
damaged in transit.
1.1.3 When poor condition under harsh preservation or
shipping conditions caused, inspect and confirm this
meter without delay.
1.1.4 Test leads must be in good condition. Before using
verify that the insulation on test leads is not damaged
and/or the leads wire is not exposed.
1.1.5 Full compliance with safety standards can be
guaranteed only if used with test leads supplied. If
necessary, they must be replaced with the same model
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DIGITAL MULTIMETER
SAFETY INFORMATION
or same electric ratings.
1.2 DURING USE
1.2.1 Before using, you must select the right input jack,
function and range.
1.2.2 Never exceed the protection limit values indicated in
specifications for each range of measurement.
1.2.3 When the meter is linked to a measurement circuit, do
not touch unused terminals.
1.2.4 At the manual range, when the value scale to be
measured is unknown beforehand, set the range
selector at the highest position.
1.2.5 Do not measure voltage if the voltage on the
terminals exceeds 600V above earth ground.
1.2.6 Always be careful when working with voltages above
60V DC or 30V AC rms, keep fingers behind the probe
barriers while measuring.
1.2.7 Never connect the meter leads across a voltage
source while the transform switch is in the current,
resistance, capacitance, temperature, diode, transistor
or continuity mode. Doing so can damage the meter.
1.2.8 Before rotating the transform switch to change
functions and ranges, disconnect test leads from the
circuit under test.
1.2.9 Never perform resistance, capacitance, temperature,
transistor, diode and continuity measurements on live
circuits.
1.2.10 Never use the meter under the condition of the
explosive air, steam or dirt.
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DIGITAL MULTIMETER
SAFETY INFORMATION
1.2.11 If any faults or abnormalities are observed, the meter
can not be used any more and it has to be checked out.
1.2.12 Never use the meter unless the rear case is in place
and fastened fully.
1.2.13 Please do not store or use meter in areas exposed to
direct sunlight, high temperature, humidity or
condensation.
1.3 SYMBOLS
Important safety information, refer to the operating
manual.
Double insulation（Protection classΙΙ）.
CAT III Overvoltage (Installation) category III, Pollution
Degree 2 per IEC1010-1 refers to the level of
Impulse Withstand Voltage protection provided.
Conforms to european union directive
Earth ground
Fuse
AC Alternating current
DC Direct current
Diode
Continuity buzzer
AC or DC (alternating current or direct current)
Measurement with clamp (optional), widening the field
of applications of the meter
℃Centigrade
℉Fahrenheit
MAX.H The maximum value is being held.
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DIGITAL MULTIMETER
SAFETY INFORMATION
DATA-H This indicates that the display data is being held.
AUTO Auto range
The battery is not sufficient for proper operation.
1.4 MAINTENANCE
1.4.1 Please do not attempt to adjust or repair the meter by
removing the rear case while voltage is being applied.
A technician who fully understands danger involved
should only carry out such actions.
1.4.2 Before opening the battery cover or case of the meter,
always disconnect test leads from all tested circuits.
1.4.3 To avoid the wrong reading causing electricity attack,
when the meter displays“”, you must change the
battery.
1.4.4 For continue protection against fire, replace fuse only
with the specified voltage and current ratings: F
200mA/250V (quick acting).
1.4.5 Do not use abrasives or solvents on the meter, use a
damp cloth and mild detergent only.
1.4.6 Always set the power switch to the OFF position when
the meter is not in use.
1.4.7 If the meter is to be stored for a long period of time, the
batteries should be removed to prevent damage to the
unit.
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DIGITAL MULTIMETER
DESCRIPTION
2. DESCRIPTION
- This meter is a portable professional measuring
instrument with handsome LCD and back light easily
reading.
- Single operation of a transform switch makes
measurement convenient. Overload protection and low
battery indication are provided, this meter is ideal for use
in the fields, workshop, school, hobby and home
applications.
- This meter has function of auto range and manual range.
- This meter has function of auto power off.
- This meter is with the functions of data hold and maximum
value hold.
- When using, it can show ranges engineering unit
enunciators measuring results.
2.1 NAMES OF COMPONENTS
⑴ LCD Display
⑵ ON/OFF Button
⑶ RANGE Button
⑷ FUNC. Button
⑸ Transform Switch
⑹ 10A Jack
⑺ INPUT Jack
⑻ COM Jack
⑼ Panel
⑽ Button
⑾ DATA-H Button
⑿ MAX.H Button
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(1)
(2)
(3)
(4)
(5)
(6)
(10)
(11)
(9)
(7)
(8)
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DIGITAL MULTIMETER
DESCRIPTION
2.2 SWITCH, BUTTONS AND INPUT JACK ELUCIDATION
•ON/OFF Button
This Button is used to the switch of power.
•RANGE Button
This button is used to transform Auto range or manual
range.
•FUNC. Button
This button is used to transform function.
•DATA-H Button
This Button is used to the switch of data hold.
•MAX.H Button
This Button is used to the switch of maximum value hold.
•Button
This button is used to the switch of back light.
•Transform Switch
This switch is used to select functions and desired ranges.
•10A Jack
Input terminal for current 0 ~ 10A
•INPUT Jack
Input terminals except 10A
•COM Jack
Common terminal for measurement
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DIGITAL MULTIMETER
SPECIFICATIONS
3. SPECIFICATIONS
Accuracy is specified for a period of year after calibration and
at 18℃to 28℃（64°F to 82°F）with relative humidity to 75%.
3.1 GENERAL SPECIFICATIONS
3.1.1 Auto ranges and manual range.
3.1.2 Max. Voltage Between Terminals And Earth Ground:
600V DC or AC
3.1.3 Fuse Protection: F 200mA/250V (quick acting).
3.1.4 Operating Altitude: 2000 meters (7000 ft.) maximum
3.1.5 Display: 16mm LCD
3.1.6 Max. Show Value: 1999 (3 1/2)
3.1.7 Polarity Indication: ‘-‘ indicates negative polarity.
3.1.8 Overrange Indication: Display ‘OL’
3.1.9 Sampling Time: approx. 0.4 second
3.1.10 Unit showing: showing of function and electrical
capacity.
3.1.11 Low Battery Indication: ‘ ’ displayed
3.1.12 Auto power off time: 15 min.
3.1.13 Power Supply: 1.5V×3 AAA battery.
3.1.14 Operating Temperature: 0℃to 40℃（32°F to 104°F）
3.1.15 Storage Temperature: -10℃to 50℃（10°F to 122°F）
3.1.16 Dimension: 158×74×32 mm
3.1.17 Weight: approx. 250g（including battery）
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DIGITAL MULTIMETER
SPECIFICATIONS
3.2 ELECTRICAL SPECIFICATIONS
Circumstance Temperature: 23±5℃
Relative Humidity: < 75%
3.2.1 DC Voltage
Range Resolution Accuracy
200mV 0.1mV
2V 0.001V
20V 0.01V ±（0.7% of rdg + 2 digits）
200V 0.1V
600V 1V
- Input Impedance: 10MΩ
- Overload Protection: 200mV range: 250V DC or AC rms,
2V-600V ranges: 600V DC or AC rms.
- Max. Input Voltage: 600V DC
3.2.2 AC Voltage
Range Resolution Accuracy
200mV 0.1mV
2V 0.001V ±（0.8% of rdg + 3 digits）
20V 0.01V
200V 0.1V
600V 1V ±（1.0% of rdg + 3 digits）
- Input Impedance: 10MΩ
- Overload Protection: 200mV range: 250V DC or AC rms,
2V-600V ranges: 600V DC or AC rms.
- Frequency Range: 40 to 400Hz
- Response: Average, calibrated in rms of sine wave.
- Max. Input Voltage: 600V AC rms
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DIGITAL MULTIMETER
SPECIFICATIONS
3.2.3 DC Current
Range Resolution Accuracy
200μA 0.1μA
2000μA 1μA ±（1.2% of rdg + 3 digits）
20.00mA 0.01mA
200.0mA 0.1mA
2.000A 0.001A ±（2.0% of rdg + 10 digits）
10.00A 0.01A
- Overload Protection: μA, mA ranges: F 200mA/250V
fuse (quick acting), 2A, 10A range: unfused.
- Max. Input Current: INPUT Jack: 200mA, 10A Jack: 10A
- Voltage Drop：200µA、20mA、2A: 20mV,
2000µA、200mA、10A range: 200mV
3.2.4 AC Current
Range Resolution Accuracy
200μA 0.1μA
2000μA 1μA ±（1.5% of rdg + 5 digits）
20.00mA 0.01mA
200.0mA 0.1mA
2.000A 0.001A ±（3.0% of rdg + 10 digits）
10.00A 0.01A
- Overload Protection: μA, mA ranges: F 200mA/250V
fuse (quick acting), 2A, 10A range: unfused.
- Max. Input Current: INPUT Jack: 200mA, 10A Jack: 10A
- Frequency Range: 40 to 400Hz
- Response: Average, calibrated in rms of sine wave.
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DIGITAL MULTIMETER
SPECIFICATIONS
- Voltage Drop：200µA、20mA、2A: 20mV,
2000µA、200mA、10A range: 200mV
3.2.5 DC Current （with clamp, optional）
Range Resolution Accuracy
meter
200A 0.1mV/0.1A ±（1.2 % of rdg + 3 digits）
DC Clamp
0 to 200A 0.1A /0.1mV Typical ±（2.0 %）
meter
2000A 1mV/1A ±（1.2 % of rdg + 3 digits）
DC Clamp 0 to 2000A 1A/1mV Typical ±（2.0 %）
- Overload Protection: 250V DC or AC rms
- Max. Input Voltage: 200mV
3.2.6 AC Current （with clamp, optional）
Range Resolution Accuracy
meter
200A 0.1mV/0.1A ±（1.5 % of rdg + 5digits）
AC Clamp
0 to 200A 0.1A/0.1mV Typical ±（3.0 %）
meter
2000A 1mV/1A ±（1.5 % of rdg + 5 digits）
AC Clamp 0 to 2000A 1A/1mV Typical ±（3.0 %）
- Overload Protection: 250V DC or AC rms
- Max. Input Voltage: 200mV
- Frequency Range: 40 to 400Hz
- Response: Average, calibrated in rms of sine wave.
3.2.7 Continuity
Range Function
Built-in buzzer will sound, if resistance is
lower than 50Ω.
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DIGITAL MULTIMETER
SPECIFICATIONS
- Open circuit voltage: approx. 0.5V
- Overload Protection: 250V DC or AC rms
3.2.8 Resistance
Range Resolution Accuracy
200Ω0.1Ω±（1.0% of rdg + 3 digits）
2kΩ0.001kΩ
20kΩ0.01kΩ±（1.0% of rdg + 1 digit）
200kΩ0.1kΩ
2MΩ0.001MΩ
20MΩ0.01MΩ±（1.0% of rdg + 5 digits）
- Open Circuit Voltage: 0.25V
- Overload Protection: 250V DC or AC rms
3.2.9 Temperature
Range -20℃to 1000℃
Resolution 1℃
-20℃to 0℃±（5% of rdg + 4digits）
Accuracy 0℃to 400℃±（1% of rdg + 3digits）
400℃to 1000℃±（2% of rdg + 3digits）
Range 0℉to 1800℉
Resolution 1℉
0℉to 50℉±（5% of rdg + 4digits）
Accuracy 50℉to 750℉±（1% of rdg + 3digits）
750℉to 1800℉±（2% of rdg + 3digits）
- Overload Protection: 250V DC or AC rms
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DIGITAL MULTIMETER
SPECIFICATIONS
3.2.10 Capacitance
Range Resolution Accuracy
20nF 0.01nF ±（4.0% of rdg +10digits）
200nF 0.1nF
2µF 0.001µF
20µF 0.01µF ±（4.0% of rdg + 3 digits）
200µF 0.1µF
1000µF 1µF
- Overload Protection:
20nF~20µF ranges: F 200mA/250V fuse (quick acting).
200µF/1000µF ranges: No Overload Protection.
- Open circuit voltage: approx. 0.5V
- Overload Protection: 250V DC or AC rms
3.2.11 Diode
Range Resolution Function
1mV Display :read approximate
forward voltage of diode
- Forward DC Current: approx. 1mA
- Reversed DC Voltage: approx.1.5V
- Overload Protection: 250V DC or AC rms
3.2.12 Transistor hFE
Range Function
hFE Display: read approximate hFE value
(0-1000) of transistor under test (ALL
TYPE)
- Base Current: approx. 2µA, Vce: approx. 1V
- Overload Protection: F 200mA/250V fuse (quick acting)
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16
DIGITAL MULTIMETER
OPERATING INSTRUCTION
4. OPERATING INSTRUCTION
4.1 POWER-UP
Press the ‘ON/OFF’button to turn the meter ON or OFF.
4.2 DATA HOLD
If you need data hold when measuring, you can put on
‘DATA-H’ button, it will hold the reading; if you put the button
again, data hold is not continue.
4.3 MAXIMUM VALUE HOLD
If you need data hold when measuring, you can put on
‘MAX.H’ button, it will hold the maximum value; if you put the
button again, maximum value hold is not continue.
4.4 FUNCTION TRANSFORM
Put down the ‘FUNC.’ when measuring the current and
voltage. Meter will be transformed between DC and AC range.
Put ‘FUNC.’ when measuring the temperature, meter will
transform between ℃ and ℉range. Put ‘FUNC.’ when
measuring the diode and continuity, meter will transform
among them.
4.5 RANGE TRANSFORM
The auto range is used when measuring the current, voltage,
capacitance and resistance. Put down the ‘RANGE’ if the
manual range is needed. Each time you put down, range will
go upward; the minimum range is transformed if ‘RANGE’ is
put down at the maximum range. If the ‘RANGE’ is put down
more than two seconds, auto range is used again.
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DIGITAL MULTIMETER
OPERATING INSTRUCTION
4.6 BACK LIGHT
If the light is dark to make the reading difficult when
measuring, you can press ‘ ‘ button to turn on the back
light, which will last for 15 seconds. Continuous pressing the
button for two seconds will turn off the back light.
NOTE:
•LED is the main source of back light. Its working current is
large, although the meter has the timer equipment (time is
15 seconds and it will off automatically after 15 seconds);
often use back light will shorten the battery life, you’d
better not to use the back light so frequently if it’s not
necessary.
•When the battery voltage is less than 4V, it will show
‘‘. But if you use back light at the same time, maybe
‘’ will come up even if the battery voltage is more than
4V, because the working current is higher and the voltage
will decline. (When ‘ ’ shows, the accuracy of
themeasurement can not be assured.)
You need not replace the battery. When you use normally
(back light is not using), ‘ ’ will not show up. You need
replace it till ‘ ’show again.
4.7 AUTO POWER OFF
If there’s no any operation within fifteen minutes after power
is on, meter will auto power off with five short sounds and a
long sound in a minute.
After auto power off, if stir the transform switch or put down
any button of ‘FUNC.’, ‘DATA-H’, ‘MAX.H’, ‘RANGE’, meter
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DIGITAL MULTIMETER
OPERATING INSTRUCTION
will recover the working condition.
If presses the ‘FUNC.’ when power is on, auto power off
disable.
4.8 PREPARATION FOR MEASUREMENT
4.8.1 Put on the ‘ON/OFF’ button. If the battery voltage is
less than 3.8V, display will show ‘ ’, the battery
should be changed at this time.
4.8.2 The ‘ ’ besides the input jack shows that the input
voltage or current should be less than specification on
the sticker of the meter to protect the inner circuit from
damaging.
4.8.3 Select a function and a range for the item to be
measured through rotating the transform switch
accordingly. When the value scale to be measured is
unknown beforehand, set the range selector at the
highest position.
4.8.4 When connection, first connect to the public testing line,
then to the electriferous testing line. When you’ll
remove it, you should remove the elecriferous one.
4.9 MEASURING DC VOLTAGE
WARNING
You can’t input the voltage which more than 600V DC,
it’s possible to show higher voltage, but it’s may
destroy the inner circuit.
Pay attention not to get an electric shock when
measuring high voltage.
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DIGITAL MULTIMETER
OPERATING INSTRUCTION
4.9.1 Connect the black test lead to the COM jack and the
red test lead to the INPUT jack.
4.9.2 Set the transform switch
at the V range position.
4.9.3 Put down the ‘FUNC.’ to
enter the DC
measurement. Auto
range or manual range
can be transformed by
putting the ‘RANGE’.
4.9.4 Connect test leads
across the source or load
under measurement.
4.9.5 You can get a reading
from LCD display. The
polarity of the red test lead connection will be indicated.
NOTE:
•At the little voltage range, the meter will show unsteady
reading when test leads haven’t reach the circuit, it’s
normal because the meter is very sensitivity. When test
leads touch the circuit, you can get the true reading.
•At the manual range mode, when only the figure ‘OL’ is
displayed, it indicates overrange situation and the higher
range has to be selected.
•At the manual range mode, when the value scale to be
measured is unknown beforehand, set the range selector
at the highest position.
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DIGITAL MULTIMETER
OPERATING INSTRUCTION
4.10 MEASURING AC VOLTAGE
WARNING
You can’t input the voltage which more than 600V rms
AC, it’s possible to show higher voltage, but it’s may
destroy the inner circuit.
Pay attention not to get an electric shock when
measuring voltage.
4.10.1 Connect the black test lead to the COM jack and the
red test lead to the INPUT jack.
4.10.2 Set the transform switch
at the V range position.
4.10.3 Put down the ‘FUNC.’ to
enter the AC measurement.
Auto range or manual
range can be transformed
by putting the ‘RANGE’.
4.10.4 Connect test leads
across the source or load
under measurement.
4.10.5 You can get reading from
LCD.
NOTE:
•At the little voltage range, the meter will show unsteady
reading when test leads haven’t reach the circuit, it’s
normal because the meter is very sensitivity. When test
leads touch the circuit, you can get the true reading.
•At the manual range mode, when only the figure ‘OL’ is
displayed, it indicates overrange situation and the higher
range has to be selected.
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