Digital multimeter technical features and panel operation instructions
A digital multimeter is a small digital multimeter with a three and a half digit LCD display. It can measure AC and DC voltage, AC and DC current, resistance, capacitance, transistor beta value, diode conduction voltage, and circuit short circuiting. The measurement function and range are changed by a rotating band switch, with a total of 30 levels.
The maximum display value of this multimeter is ± 1999, which can automatically display "0" and polarity. When overloaded, it displays "1" or "-1". When the battery voltage is too low, it displays the "←" symbol. The buzzer is used for short circuit inspection.
Technical characteristics of digital multimeter
1. Measurement range
⑴ AC and DC voltage (AC frequency ranging from 45Hz to 500Hz);
The measurement ranges are 200mV, 2V, 20V, and 1000, with a DC accuracy of ± (0.8%+2 words of reading) or less and an AC accuracy of ± (1%+5 words of reading);
The input impedance is 10M Ω in DC mode and 10M Ω and 100PF in AC mode.
⑵ AC and DC currents
The measurement ranges are 200 μ A, 2mA, 200mA, and 10A, with a DC accuracy of ± (1.2%+2 words of reading) and an AC accuracy of ± (2.0%+5 words of reading). The maximum voltage load is 250mV (AC RMS).
⑶ Resistance:
The range is divided into six levels: 200 Ω, 2k Ω, 200k Ω, 20M Ω, and 20M Ω. The accuracy is ± (2.0% of the reading+3 words).
⑷ Diode conduction voltage:
The range is 0-1.5V, and the test current is 1mA ± 0.5mA.
⑸ Detection of transistor beta value:
The testing conditions are: VCE=2.8V, IB=10 μ A.
⑹ Short circuit detection:
Test circuit resistance<20 Ω± 10 Ω 2. Sampling time: TS=0.4S.
Panel and operating instructions
1. Monitor
Three and a half digit LCD display screen
2. Power switch
Press to turn on the power, and turn it off when not in use.
3. Capacitor measurement socket
When measuring capacitance, insert the capacitor pins into the socket.
4. Function range switch
Choose different measurement functions and ranges.
5.10A current socket (cannot measure current greater than 10A)
When measuring AC and DC currents greater than 200mA but less than 10A, the red probe should be inserted into this 10A current socket.
6. Current socket
When measuring AC and DC currents less than 200mA, the red probe should be inserted into this current socket.
7. V/Ω socket
When measuring AC and DC voltage, resistance, diode conduction voltage, and short circuit detection, the red probe should be inserted into this V/Ω socket.
8. The black probe of the grounding common terminal "COM" socket should always be inserted into this grounding socket.
9. Beta value test socket
Insert the collector, base, and emitter of the tested transistor into the "C", "B", and "E" sockets respectively, paying attention to distinguishing whether the transistor is NPN or PNP type.
