Victor 81D User manual

DIGITAL MULTIMETER
OPERATION MANUAL
I. General
This is equipped with the LCD display
of text height 18.9mm, is a 3 3/4 digital
multimeter which has the merits of clear
reading, stable performance and high
reliability.
It could be used to measure DC voltage,
AC voltage, DC current, AC current,
resistance, temperature, capacity, frequency /
duty cycle, diode and make on-and-off test.
Meanwhile, it is available for unit symbol
display, automatic/manual range switching,
automatic power off and alarm function. The
complete machine takes an integrated circuit
which can directly drive LCD 8-bit
microprocessor and double-integrating A/D

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switching and a digital display drive offering
high resolution and high precision. Due to its
complete functions, high measurement
accuracy and convenient operation, the
multimeter is the ideal tool in laboratory and
factory as well as for radio fans and family.
Ⅱ. Open-package Inspection
Open the package box and take out the meter,
check carefully if the following accessories
are absent or damaged. If there is any absence
or damage, please contact the distributor
immediately.
Digital Multimeter 1 PC
Instruction Manual 1 copy
Test Leads 1 pair
Temperature Probe (K-Thermocouple) 1 PC
AAA (1.5v) 7# batteries 2 PCs

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Holster 1 PC
III. Safety Considerations
The design of meter is in accordance
with IEC1010 clause (the safety standard
issued by International Electrotechnical
Commission). Prior to the operation of the
instrument, please first read the safety
considerations.
1. When DC voltage above 30V, AC voltage
above 25V, current above 10mA, AC
power line with inductive load or power
line during electric fluctuation is measured,
please beware of electric shock.
2. Prior to measurement, check if the
measurement function switch is at the
correct position. Check if the meter pen is
contacted reliably, connected correctly, and

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grounded well and etc. in order to avoid
electric shock.
3. Only if the meter is used with the matched
meter pen, can it meet the requirement of
safety standard. When the line of the meter
pen is damaged, it is necessary to replace
another one of the same model or the same
electrical specification.
4. Don’t use other unconfirmed or
disapproved protector tube to replace the
protector tube inside the meter. Only the
protector tube of the same model or same
specification can be replaced. Before the
replacement, the test leads must leave the
measuring point and ensure there is no any
signal at the input terminal.
5. Don’t use other unconfirmed or
disapproved battery to replace the battery

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inside the meter. Only the battery of the
same model or same electrical
specification can be replaced. Before the
replacement, the test leads must leave the
measuring point and ensure there is no any
signal at the input terminal.
6. When the electrical measurement is made,
never let your body gets in touch with the
ground directly, and don’t touch uncovered
metal terminal, output port, lead clamp and
etc. where earth potential may exist. Dry
clothes, rubber shoes, rubber cushion and
other insulating material are usually used
to keep your body insulated against the
ground.
7. Don’t store and use it in the
high-temperature, high-humidity,
inflammable and strong magnetic field

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environment.
8. It may do damage to the meter and
endanger the operator’s safety if the
voltage value beyond the permitted
ultimate voltage value is measured. The
ultimate voltage value permitted for
measurement is marked on the instrument
panel, and never measure the value
exceeding the standard. Don’t input the
ultimate value out of regulation in order to
avoid electric shock and the damage to the
meter.
9. When the test leads is inserted into the
current socket, don’t measure any voltage
for fear that the meter should be damaged
and the operator’s safety be endangered.
10. Don’t try calibrating or repairing the
meter. When necessary, only the qualified

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professional personnel who have had
special training or gained approval can
make it.
11. During measurement, the requirement of
measurement function must be in
accordance with LCD display. Please be
sure to disconnect the line of the test leads
with the measured object first and ensure
there is no any input signal. It is forbidden
to switch the function/range selection
switch during measurement
12. When “ ” ”is shown on LCD
display, please replace battery
immediately to ensure the measurement
precision.
13. It is not allowed to insert the test leads
into the current terminal to measure
voltage!

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14. Please don’t change the circuits of the
meter freely for fear that the meter be
damaged and the safety be endangered.
15. Description of Safety Symbols
IV. Instrument Panel& Button Function
Description
1. Instrument Model Number
2.LCD Display: Display the
measured data and unit.
3. Function Button
3.1.SELECT(function
switch)：Press this
F
Hz
FUSED
400mA MAX
mA
V
COM
10A
C
Hz
1
2
3-1
3-2 3-3
3-4
4
5-1
5-2 5-3

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button, the function could switch
between DC/AC/
3.2. RANGE(auto/manual range switch):
it’s auto range switch after power-on,
press this key switch to manual range.
Under the manual range mode , Every
pressing to this key will make the range
get to upper one.press this key for more
than 2 sec. will back to auto range
mode .
3.3 . HOLD（Data Hold） ： Press this button,
the reading is locked; Press it again, the
lock is cleared and enter into normal
measurement status.
3.4 REL (Relative Value Measurement):
The relative value measurement of all
functions could be conducted by
pressing this button except the Hz/Duty

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function.(Frequency/duty cycle):press
this key to select frequency or duty
cycle measurement mode.
4.Knob Switch：It could be used to change
the measurement function and range.
5. Input Terminals
5.1.Current, Voltage, Diode, Resistance,
Capacity, Frequency, Buzzer,
Temperature“-”Input terminal.
5.2.10A“+”input terminal.
5.3.Voltage、Diode、Resistance, Capacity,
Frequency, Buzzer, Temperature and“+”
Input terminal with current less than
400mA.
V. Other Functions
Automatic Power off
During measurement, the meter will