DIGITAL MULTIMETER USERS MANUAL
1.
GENERAL DESCRIPTION
This 31/2 Digit Highly Stable multimeter uses two AA (1.5V) battery. It has a LCD with
22mm digit display, which makes the reading clearer and the operation more convenient. It
can test DCV, ACV, DCA, ACA, resistance, NCV, temperature, transistor, diode, and
continuity test. This meter also has Max Min Hold function with unit symbol display, can
work in both auto and manual range, and provides auto power off, backlight and warning
functions. To assure high accuracy and resolution, it adopts an 8-bit microprocessor and a dual
integral A/D convertor IC .It is an ideal tool for labs, factories and radio-technology.
2.
SAFETY PRECAUTIONS
The instrument is designed according to IEC1010 standard (safety standard issued by
International Electro technical Committee). Please read the following carefully before
operation.
2.1 Check the connection and insulation of test leads to avoid electric shock.
2.2 To avoid electric shock and damage to the meter, do not input voltage higher than DC
1000V or AC 750V during measurement.
2.3 Use caution when working with voltages above DC 60V or AC 40V.
2.4 Select correct function and range to avoid shock and fault operation.
2.5 Please move the test leads away from test points when switching the Range.
2.6 Please don’t input voltage in current terminal.
2.7 Introduction for safety symbols:
“
” exists high voltage, “ ” GND, “ ” dual insulation, “ ” Operator must refer to
manual, “
” Low battery indication.
3.
FEATURES
3.1 General Characteristics
3.1.1 Display: LCD;
3.1.2 Max display: 2,000 (3 1/2 digits, auto polarity, and unit symbol display);
3.1.3 Measurement method: Analog to digital converter (in micro processor ADC+MCU);
3.1.4 Sampling rate: approx.3 times/sec.
3.1.5 Over-range display: “OL” displayed.
3.1.6 Low battery indicator: “
”
3.1.7 Working environment: (0
～
40)℃, relative humidity: <80%;
3.1.8 Store condition: (-10
～
50)℃, relative humidity: <80%
3.1.9 Battery: 2 X 1.5V battery (AAA);
3.1.10 Dimension: 170×86×35mm (length*width*height);
3.1.11 Weight: approx. 290g (including battery);
3.1.12 Accessories: test leads, user manual, temperature probe, gift box and batteries.
3.2 Technical Features
3.2.1 Accuracy: ± (a% × reading data + digits). To assure accuracy, the environment
temperature should be (23±5)
℃
, relative humidity should <75%.
One year accuracy guarantee since production date.
3.2.2 DC Voltage
（
DCV
）
Range
Accuracy
Resolution
200mV
±(0.5%+4)
0.1mV
2V
1mV
20V
10mV
200V
100mV
1000V
±(1.0%+4)
1V
Input impedance: at 200mv range >40MΩ, at other ranges is 10MΩ.
Overload protection: 1000V DC or 750V AC peak value
3.2.3 AC Voltage
（
ACV
）
Range
Accuracy
Resolution
2V
±(0.8%+6)
1mV
20V
10mV
200V
100mV
750V
±(1.0%+6)
1V
Input impedance: 10MΩ.
Overload protection: 1000V DC or 750V AC rms
Frequency response: at 750V range: 40~1000Hz, at other ranges: 40~2000Hz
Displaying: True RMS response (calibration based on sine wave RMS)
3.2.4 DC Current
（
DCA
）
Range
Accuracy
Resolution
200uA
±(1.0%+5)
0.1μA
2000uA
1μA
20mA
10μA
200mA
100μA
2A
1mA
20A
±(2.0%+5)
10mA
Maximum voltage drop: 200mV for all ranges.
Maximum input current: 20A (for 15 seconds).
Over load protection: 0.2A/250V fuse and 13A/250V fuse.
3.2.5 AC Current
（
ACA
）
Range
Accuracy
Resolution
200uA
±(1.5%+5)
0.1μA
2000uA
1μA
20mA
10μA
200mA
100μA
2A
1mA
20A
±(2.0%+10)
10mA
Maximum voltage drop: 200mV for all ranges.
Maximum input current: 20A (for 15 seconds).
Over load protection: 0.2A/250V fuse and 13A/250V fuse.
Frequency response: 40~100Hz under 20A range, 40
～
400Hz at other ranges.
3.2.6 Resistance
（
Ω
）
Range
Accuracy
Resolution
200Ω
±(0.8%+5)
0.1Ω
2kΩ
±(0.8%+1)
1Ω
20kΩ
10Ω
200kΩ
100Ω
2MΩ
1kΩ
20MΩ
±(1.2%+5)
10kΩ
Open circuit voltage: >500mV
Overload protection: 250V DC/AC peak value.
3.2.7 Transistor triode (hFE)
Measurement
Range
Test Conditions
NPN or PNP
0
～
1000
Base current is approx
15uA, Vce is about 1.2V
3.2.8 Diode and Continuity Test
Range
Description
Test Conditions
Diode forward voltage drop
Forward DC current is
approx 0.8mA, reverse
voltage is approx 2.2V.
When the resistance under test is
less than 50Ω, buzzer sounds
continuously.
Open circuit voltage: 2.2V
Overload protection: 250V DC/AC peak value
WARNING: Do not apply any voltage in this range.
3.2.9 Temperature (
℃
/
℉
)
Range
Accuracy
Resolution
-40℃~1000℃
＜
400℃ ±(1.0%+5)
≥400℃ ±(1.5%+15)
1℃
0F~1832℉
＜
750℉ ±(1.0%+5)
≥750℉ ±(1.5%+15)
℉
Thermocouple: K type
WARNING: do not input voltage at this range!
OPERATION INSTRUCTION
4.1 Panel Description
(See picture)
①
. NCV detector area and indicator light.
②
.LCD: Display the data and unit symbol.
Number
Feature
Indication
1
APO
Auto power off symbol.
2
Low battery indication. Warning: To avoid error readings,
which could lead to possible electric shock or personal
injury, please replace the battery in time.
3
-
Indicates negative readings.
4
AC
AC voltage or current measurement.
5
DC
DC voltage or current measurement.
6
AUTO
Auto range mode.
7
Diode test mode
8
Continuity beeper is on.
9
HOLD
Display Hold is active.
10
MAX MIN
△
Max&Minimum value recording mode.
Null
11
hFE
℃/℉
MΩ, kΩ, Ω
mV, V
uA, mA, A
NCV
hFE (Triode magnification measurement)
Degrees Celsius, Degrees Fahrenheit
Megohm, Kilohm, Ohm
Millivolts, Volts
Microamp, Milliamp, Amperes (A)
Non-contact voltage detector.
③
Function Button
③
-1
LIGHT key: press “ ” light key to turn on the backlight, the backlight can last 15
seconds. During 15 seconds, press “ ” light key again will turn off the backlight.
③
-2 MAX / MIN: Recording of minimum and maximum values
1) Press MAX/MIN into MAX mode, which will store the maximum value of measurements;
Press it again to start MIN mode, which will store the minimum value of measurements.
2) Under MAX/MIN mode, it will start manual range automatically. Under this mode,
functions like HOLD, RANGE, and DC/AC will not be available.
3) Under MAX/MIN mode, it will store maximum or minimum values automatically.
4) Under MAX/MIN mode, auto power off can’t be used.
5) Press MAX/MIN for 2 seconds it will exit MAX/MIN mode.
③
-3 HOLD key: press HOLD key to enter HOLD mode, the current value will be hold, and
symbol HOLD will be displayed. Press HOLD again can exit the HOLD mode.
③
-4 RANGE key: for choosing auto or manual range. The meter defaults to auto range in
measurement function and “AUTO” symbol is displayed. To Enter Manual Range mode Press
RANGE key. Each Press of RANGE key Increments the range, when the highest range is
reached ,the meter wraps to the lowest range .To exit the manual range mode press and hold
the Range key for more than 2 seconds.
③
-5 SELECT key (yellow):
③
-5-1 At
range, press yellow key can choose DC or AC measurement. At
range,
press yellow key can choose diode or continuity test. At temperature range, press yellow key
can choose
℃
/
℉
.
③
-5-2 When there is no measurement for 15 minutes, the meter will auto power off and enter
sleep mode. In one minute before Sleep mode, the buzzer will beep 5 times to remind user.
Press any button or turn the rotary switch will exit the Sleep mode. Press yellow key to Power
on the meter from the Sleep mode or Press and hold the yellow button when the meter is ON ,
it will cancel auto power off function.
④
.Rotary switch: used to change the range and choose functions.
