Victor VC921 User manual

DIGITAL MULTIMETER
OPERATION MANUAL
WARNING
To avoid electric shock or injured
or damage the instrument, please
read the manual carefully before
operation.
Ⅰ. SAFETY RULES
This series meter meets the
standard of IEC1010. ead it
before operation.
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1．Check the case of the meter
and test leads before operation.
2．Do not input over range when
testing.
3. Be careful when measuring
voltage over ACV 40V or DCV
60V.
4．When measuring, must select
correct function and range.
5．The test lead should be keep
away from the tested point when
change the function.
6. Do not try to modify the circuit,
Or you may damage the instrument
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and endanger personal safety.
7. Safety symbols
“ ” exists high voltage , “ ”
dual insulation ,“ ” warning
8．Electric symbols
“ ”GND， “ ” low battery
“ ” AC “ ” DC “
”continuity test “ ”diode “
”relative value measurement
“ ”auto range
II.KEY FUNCTION
1. EL: press this key ,readings
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back to zero , enter into relative
measurement ,LCD display “
” symbol, press it again, out from
the relative value measurement
function .when at Hz range, can
switch to frequency or duty cycle
(0.1~99.9%) measurement mode.
2. ANGE key :selecting operation
mode of auto range or manual
range .the default mode of this
meter is auto range , LCD display“
” symbol, press this key will
change to manual range, press it
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one more time to increase a new
range, from low to high cycle in
turn .press the key for more than 2
seconds, will back to auto range
mode.
Ⅲ. SPECIFICATION
3-1．GENERAL
3-1-1 ．Displaying : LCD
displaying
3-1-2．Max. indication: 3999 （3
3/4）, auto polarity indication
3-1-3 ．Measuring method: dual
slope A/D transfer
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3-1-4 ．Sampling rate: approx. 3
times/sec
3-1-5 ．Over range indication:
displays “OL”
3-1-6 ．Low battery indication: “
” symbol displays
3-1-7 ．Operation: (0 ～
40)℃，relative humidity <80%
3-1-8．Power：2×1.5V battery
3-1-9．Meas.:124×80×20 mm
3-1-10 ．Weight: approx.
140g（including battery）
3-1-11. Accessories: instruction
manual, gift box and battery
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3-2．TECHNICAL DATA
3-2-1 ．Accuracy: ± （DG×a%
+ digit ） at (23±5) ,<75% H℃
one year guarantee from
production date
3-2-2.DCV
ANG
EACCU ACY ESOLUTION
400mV
±(0.5%+4)
0.1mV
4V 1mV
40V 10mV
400V 100mV
600V ±(1.0%+4) 1V
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Input resistance： 10MΩ
Overload protection: 400Mv
range:250V MS ＜
10seconds ;other
ranges 600V MS ＜
10seconds .
3-2-3. ACV True MS
Measurement
ANGE ACCU ACY ESOLU7TION
400mV ±(1.5%+6) 100μV
4V
±(0.8%+6)
1mV
40V 10mV
400V 100mV
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600V ±(1.0%+6) 1V
Input resistance: 10MΩ
Overload protection: 400mV
range: 250V MS ＜
10seconds(manual range only).
Other ranges 600V MS ＜
10seconds.
Frequency response: Sine wave
and triangular wave :
(40~1000)Hz, other waveform:
( 40~400)Hz
Displaying: True MS response
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3-2-4. CONTINUITY TEST
Overload protection: 250V MS
Warning: do not input voltage at
this range.
ange Display Test Condition
Buzzer
sound at
less than
(50±30)Ω
OCV: about 0.5V
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ANGE DISPLAYING
VALUE
TEST
CONDITION
Forward
voltage drop
of diode
Forward
DCA is
approx.
0.5mA ，bac
kward
voltage is
approx. 1.5V
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3-2-5. DIODE
Overload protection:250V MS
Warning: do not input voltage at
this range.
3-2-6. ESISTANCE（Ω）
ANG
EACCU ACY ESOLUTION
400Ω ±(0.8%+5) 0.1Ω
4kΩ
±(0.8%+4)
1Ω
40kΩ 10Ω
400kΩ 100Ω
4MΩ 1kΩ
40MΩ ±[1.2%+ 5] 10kΩ
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OCV: more than 400mV
Overload protection: 250V MS.
NOTE: At 400Ω range, you should
make the test leads short to
measure the wire
resistance, then, subtracts
from the real measurement.
3-2-7. CAPACITANCE
ANG
EACCU ACY ESOLUTION
4nF ±(5.0%+40) 1pF
40nF ±(3.5%+8) 10pF
400nF 100pF
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4uF 1nF
40uF 10nF
2000uF ±(5.0%+8) 100 nF
Overload protection: 250V MS
Warning: do not input voltage at
this range.
3-2-8. Frequency(Hz/DUTY)
ange Accuracy esolution
100Hz ±(0.5%
+4)
0.01Hz
1000Hz 0.1Hz
10kHz 1Hz
100kHz 10Hz
1MHz 100Hz
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10MHz 1kHz
Input sensitivity: 3V Vp-p ( range
10MHz: more than 3.5V Vp-p)
Overload protection: 250V DC/AC
peak value.
Ⅳ. OPERATION
4-1．DCV MEASUREMENT
4-1-1. Set the knob to a proper “V”
range.
4-1-2. The default mode of this
meter is auto range , LCD
display“ ” symbol, press
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“ ANGE” key change to
manual range, it can select the
range of
400mV,4V,40V,400V,600V.
4-1-3 ．connect the
test lead to the circuit under
tested, the voltage and polarity
of the point which the red test
lead connect to will shown on
LCD.
NOTE:
1．If LCD displays “OL” when
you use manual range, it
means over range, should set
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the knob to a higher range.
2．Do not input voltage over DC
600V, or, the circuit might be
damaged.
3．Be careful when measuring
high voltage circuit.
4-2．ACV MEASUREMENT
4-2-1. Set the knob to a proper “V”
range.
4-2-2. The default mode of this
meter is auto range , LCD
display“ ” symbol, press
“ ANGE” key change to
manual range, it can select the
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range of
400mV,4V,40V,400V,600V.
4-2-3 ．Connect the
test lead to the circuit under tested,
the voltage value of the two point
which the test lead connect to will
shown on LCD.
NOTE:
1．If LCD displays “OL” , it
means over range, should set
the knob to a higher range.
2．Do not input voltage over
600V，or, the circuit might be
damaged.
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3．Be careful when measuring
high volt circuit.
4-3．CONTINUITY TEST
4-3-1. Set the knob to “ ”
range.
4-3-2.Apply test leads to two
points of tested circuit, if the
inner buzzer sounds, the
resistance is less than
(50±30)Ω.
NOTE:
Do not input any voltage at this
range .
4-4．DIODE MEASUREMENT
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4-4-1.Set the knob to “ ”
range,
4-4-2.Positive measurement:
connect the red test lead to
the anode terminal and the
black one to the cathode
terminal of the diode under
tested. The LCD will
display the approx value of
the diode forward voltage
drop.
4-4-3. everse measurement:
connect the red test lead to
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