twintex TM287, Instruction Manual

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Digital True RMS Multimeter Instruction Manual
1. GENERAL DESCRIPTION
This multimeter with highly stable performance is a reliable 3 6/7 digit digital multimeter. It uses the LCD with 23mm-high figure to make the
reading clear and make operation more convenient.
This multimeter can test DCV, ACV, VSD, DCA, ACA, resistance, capacitance, frequency, temperature, duty cycle, transistor, diode, and continuity.
This meter holds functions including true RMS, analog bar and unit symbol display, data holding, relative value measuring, maximal/minimal value
measuring, auto/manual range switching (RANGE), 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 conversion IC as its core which can drive LCD directly. 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 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 When measuring voltage higher than DC 60V or AC 40V, please be careful.
2.4 Select correct function and range to avoid fault operation.
2.5 Please move the test leads away from test points when switching the function.
2.6 Please don’t input voltage in current terminal.
2.7 Please don’t modify the circuit arbitrarily, it may cause safety problem
2.8 Introduction of safety symbol:
“ ” 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: 6000 (3 6/7) digits, automatic polarity, unit symbol and 61 section analog display
；
3.1.3 Measurement method: double integral A/D conversion;
；
3.1.4 Sampling rate: approx.3 times/sec.
3.1.5 Over-range display: “OL” displayed in the highest digit.
3.1.6 Low battery display
：
“ ”
3.1.7 Working environment: (0
～
40)
℃ , relative humidity: <80% ；
3.1.8 Store condition: (-10
～
40)
℃ , relative humidity: <80%
3.1.9 Battery
：
1 piece 9V battery
（
6F22
）；
3.1.10 Dimension: 185×93×35mm (length*width*height);
3.1.11 Weight: approx..290g
（
(including battery);
3.1.12 Accessories: test leads, user manual, temperature probe, crocodile clip, gift box, and 1*9V battery.
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 guarantee since production date.
3.2.2 DC voltage (DCV)
Range Accuracy Resolution
600mV ±(1.0%+5) 0.1mV
6V
±(0.5%+3)
1mV
60V 10mV
600V 100mV
1000V ±(1.0%+3) 1V
Input impedance: approx. 10MΩ
Overload protection
：
1000V DC or AC peak value 750V.
3.2.3 AC voltage (ACV True RMS)
Range Resolution Frequency response/ Accuracy
6V 1mV 50Hz~5kHz
：
±(1.0%+10) 5kHz~20kHz
：
±(1.5%+10)
60V 10mV
600V 100mV
＜
200V 50Hz~5kHz &
≥200V 50Hz~1kHz
：
±(1.0%+10)
750V 1V 50Hz~1kHz
：
±(1.0%+10)
Input impedance: approx. 10MΩ
Overload protection
：
1000V DC or AC peak value 750V.
Display: True RMS
3.2.4 Variable Frequency Voltage True RMS
（
VSD-V True RMS
）
Range Resolution
Frequency response/ Accuracy
30Hz~60Hz 60Hz~200Hz
6V 1mV
±(2.0%+10) ±(5.0%+10)
60V 10mV
600V 100mV
±(3.0%+10) *
750V 1V
Input impedance: approx. 10MΩ
Overload protection
：
1000V DC or AC peak value 750V.
Display: True RMS
3.2.5 DC Current
（
DCA
）
Range Accuracy Resolution
600uA
±(1.0%+3)
0.1μA
6000uA
1μA
60mA
10μA
600mA
100μA
6A
±(2.0%+5)
1mA
20A 10mA
Maximum voltage drop: 300mV for mA and A range.
Maximum input current: 20A for 15 seconds.
Overload protection
：
0.5A/250V fast action fuse for mA fuse
；
13A/250V fast action fuse for A input.
3.2.6 AC Current
（
True RMS
）
Range Accuracy/Frequency response Resolution
600uA
±(1.2%+20) / (40Hz-5KHz)
0.1μA
6000uA
1μA
40mA
10μA
600mA
100μA
6A ±(1.5%+20) / (40Hz-400Hz) 1mA
20A ±(2.5%+20) / (40Hz-400Hz) 10mA
Maximum voltage drop: 300mV for uA, mA and A range.
Maximum input current: 20A for 15 seconds.
Overload protection: 0.5A/250V fast action fuse, 13A/250V fast action fuse.
Display: True RMS
3.2.7 Resistance (Ω)
Range Accuracy Resolution
600Ω
±(0.8%+5)
0.1Ω
6kΩ
±(0.8%+3)
1Ω
60kΩ 10Ω
600kΩ 100Ω
6MΩ 1kΩ
30MΩ
±(1.2%+5)
10kΩ
Open circuit voltage: 600mV
Overload protection: 250V DC/ AC peak
NOTE: At 600 Ω range, connect the test leads to measure the wire resistance, then subtracts it from the real measurement, or press “REL” to clear
the wire resistance and read the value directly.