Mastech MS8221C User manual

1
DIGITAL
MULTIMETER
INSTRUCTION MANUAL

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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)
(12)

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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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