Mastech MS8218 User manual

MS8218 True RMS Multimeter
Contents
Contents
Chapter 1 Safety Information
◎ Meter Safety Standards………………………………………………………………………………………………….
◎ Warning………………………………………………………………………………………………………………….
◎ Limited Guarantee and the Liability Range……………………………………………………………………………..
Chapter 2 Introduction to the Meter
◎ Characteristics………………………………………………………………………………………….……………..…
◎ Explanation on Front Panel……………………………………………………………………………………………...
◎ Understanding Display Screen…………………………………………………………………………………………..
◎ Function Descriptions……………………………………………………………………………………..…………….
Chapter 3 Operation Methods
◎ ACV/dBm Measurement…………………………………………………………………………………………………
◎ DCV/DCV+ACV Measurement…………………………………………………………………………………………
◎ DC mV/AC mV /DC mV+AC mV Measurement……………………………………………………………………….
◎ Logic Frequency/Duty Ratio Measurement……………………………………………………………….…………….
◎ Diode Measurement……………………………………………………………………………………………………..
◎ Resistance/continuity Measurement…………………………………………………………………………………….
◎ Capacitance Measurement………………………………………………………………………………………………
◎ DC μ A /AC μ A/DC μ A +AC μ A Measurement…………………………………………………………………
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MS8218 True RMS Multimeter
Contents
◎ DC mA/AC mA/DC mA +AC mA Measurement……………………………………….………………………………
◎ DC Ampere/AC Ampere/DC Ampere+AC Ampere Measurement……………………….…………………………….
◎ Linear Frequency Measurement……………………………………….…………….……………….………..…………
◎ Relative Value Measurement………………………………………………………….…………………………………
◎ Maximum Value/Minimum Value/Maximum Value-Minimum Value Measurement………………………….………
◎ Backlight Control……………………………………………………………………………………………….……….
◎ Data Hold………………………………………………………………………………………………………………..
◎ Automatic Shutdown and Continuous Operation Mode Selection………………………………………………………
◎ Connected to RS-232C Interface Of Computer…………………………………………………………………………
Chapter 4 Technological Specifications
◎ General Features…………………………………………………………………………………………………………
◎ Range and Accuracy……………………………………………………………………………………………………..
Chapter 5 Maintenance
◎ Replacement of Batteries………………………………………………………………………………………………..
◎ Replacement of Fuse…………………………………………………………………………………………………….
◎ Meter Calibration………………………………………………………………………………………………………..
◎ Others ………………………………………………………………………….………..………………………………
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MS8218 True RMS Multimeter
Safety Information
Chapter 1
Meter Safety Standards
This style of digital multimeter is designed and manufactured according to the safety requirements set out by the IEC1010-1
standards for electronic test instruments and the hand-hold digital multimeters. Its design and manufacture is strictly based on
the provisions in the 1000V CAT
Ⅲ of IEC1010-1 and the Stipulation of 2-Pollution Grade.
The meter conforms to the European Union’s following requirements:89/336/EEC
(EMC Electromagnetic Compatibility ),73/23/EEC(LVD Low Voltage Protection)and 93/68/EEC(CE Mark).
Warning
Before use of the meter firstly check up if there is any crack on the outer shell or if it lacks any plastic part, and check up
whether the testing line is damaged or has any exposed metal. The meter can be used only if no any insulating problem be
found.
Carefully read the operating methods and safety prompts in this manual. Using it not based on the methods specified in
this manual may cause the meter damaged.
Non-normal meter must not be used. It should be sent for repairing.
The meter must not be used in an environment with combustible gases, steam or dust pollution.
It should be careful to work when measuring votage higher than 30Vac(effective value)or 50Vdc for such voltage having
the risk of shock. Avoid the body directly touching ground or any metal substance in which there may be ground
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MS8218 True RMS Multimeter
Safety Information
potential during measuring. The body should be kept insulated from ground with dry insulating shoes, insulating pads or
insulating clothes.
When performing measurement with a test probe your fingers should be put behind a finger-protector.
Must not try to measure a voltage higher than 1000VAC or 1000VDC,the meter may be damaged and the operator’s safety
may be threatened if the limit for voltage measurement be exceeded.
when the symbol for electric insufficiency appearing on the display screen it is necessary to replace the batteries for
avoiding the possible shock or injure resulted in by erroneous reading.
In case of replacing batteries, it is necessary firstly to pull out the testing line. AA batteries should be used and they should
be put into the meter with the proper polarity.
Must not make any voltage measurement when the testing line being inserting into the current hole.
Repair and calibration of the meter must be carried out by experienced professionals, unprofessionals should not repair and
calibrate the meter by themselves.
Limited Guarantee and the Liability Scope
This company will undertake repairs freely for any quality problem of the meter which if should be found within 18 months
from the date at which it was bought, but which not including replacement of fuse and batteries as well as any damage caused
by negligence, wrong use, pollution, change of circuit and non-normal use.
For maintenance beyond the 18-month guarantee period, the company will charge a certain repair fee and materials cost.
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MS8218 True RMS Multimeter
Introduction to the Meter
Chapter 2
Characteristics
50000 counts measurement
ACV and DCV measurements reach up to 1000V.
DC measurement accuracy reaches up to 0.03%.
0.01
Ω resistance resolution and 1 μ V voltage resolution.
Linear frequency measurement, logic frequency/duty ratio measurement.
Capacitance measurement from 0.01nf to 5000 μ F.
AC/DC true RMS measurement.
DBm measurement
Maximum value/minimum value measurement, Relative measurement.
50-segment analog bar display.
Automatic shutdown/continuous working mode selection.
Back light control.
RS-232C infrared interface.
Display, record and graphics software of computer.
Overload protection.
Sound alarm for wrong current measurement.
Secondary plasticizing meter shell, with insulating performance reaching 1000V CAT Ⅲ
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MS8218 True RMS Multimeter
Introduction to the Meter
Explanation on Front Panel
The front panel is shown as in Figure 2-1,
explanation being as follows:
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MS8218 True RMS Multimeter
Introduction to the Meter
(1) V Ω Hz end
It is the input end for all measurement functions except for current measurement, connected with a red meter probe.
(2) COM end
It is the negative input end for all measurements, connected with a black meter probe.
(3)µA/mA end
It is the positive end for measurement of µA or mA current, connected with a red meter probe.
(4)A end
It is the positive input end for measurement of 0.5A-10A current, connected with a red meter probe.
(5)Rotary switch
Used for selecting measurement functions such as voltage, current, resistance and Capacitance.
(6)POWER switch
Used for putting on or off the operating power for the meter.
(7)RANGE key
For various kinds of measurements it is used manually to select range. Under the automatic range state (AUTO displaying), it
will enter manual range state(MANUAL displaying) with a press on RANGE, after that the range will be changed with a press
on RANGE while the small digits on the left lower corner indicating the actual range. When the RANGE key being released
after pressing for two seconds the meter will return back to the automatic state. When performing logic frequency measurement
and diode measurement pressing RANGE will be void. During dBm measurement, pressing RANGE key will alter the virtual
resistance value for calculating dBm.
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MS8218 True RMS Multimeter
Introduction to the Meter
(8) SELECT key
When setting the rotary switch to a measurement function, the meter will enter its first measurement mode, while pressing the
SELECT key it is possible to select the second or the third measurement mode. However, there is only one for the diode and
Capacitance measurements.
(9)WAKE key
After the meter being automatically shutdown, by pressing the WAKE key it can be woken up to resume the measurement. In
case of pressing POWER switch(for putting on the unit) and WAKE key simultaneously, the meter will in a continuously
working state without the automatic shutdown function.
(10)MAX/MIN key
Press MAX/MIN key to enter the record state for the maximum and minimum value and simultaneously display the maximum
value. By pressing this key again it will be possible to display the minimum value and the maximum value-minimum value.
When releasing the key after pressing it for two seconds, the maximum and minimum record state will be exited. Pressing this
key will be void during frequency
、 diode measurement.
(11)REL △ key
By pressing REL △ to enter the relative measurement state, the meter will remember the value measured at the time when
pressing the key(it is called the initial value), and after that the value displayed in the meter will be equivalent to the present
value – the initial value. By pressing the key again the relative measurement state will be exited. Pressing the key will be void
during the frequency and diode measurements.
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MS8218 True RMS Multimeter
Introduction to the Meter
(12)HOLD key
Used to maintain the measurement data unchanging, by pressing the key again it will resume the measurement. When
releasing the key after pressing it for two seconds, the meter will enter the state connecting with the RS-232C interface of
computer while sending measurement information to computer. When releasing the HOLD key after pressing it for two seconds
again, it will stop to send data to the RS-232C interface.
(13)LIGHT key
By pressing this key for a time, the backlight of the LCD screen will be opened and after five seconds the meter will
automatically turn off the backlight. It is also possible to turn off the backlight by pressing the LIGHT key before the five
seconds.
(14)
～
～～
～ Hz key
During the voltage or current measurements, by pressing ～ Hz key the meter will enter the linear frequency measurement
state. At this time what being measured is the frequency of voltage or current. By pressing this key again it will exit the linear
frequency measurement state.
(15)LCD screen
Used for displaying the measuring results and various symbols.
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MS8218 True RMS Multimeter
Introduction to the Meter
Understanding Display Screen :
Figure 2—2
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