Beginners may make some mistakes when using a multimeter, and here is a detailed introduction to common mistakes and how to deal with them
1.The wrong measurement mode was selected.
The multimeter has a variety of measurement modes, such as voltage, current, resistance, capacitance, etc. Beginners may choose the wrong measurement mode, resulting in inaccurate measurement results or not getting the required information. For example, the current measurement mode is used to measure voltage, or the resistance measurement mode is used to measure current, etc. Therefore, before using a multimeter, you should understand the purpose and scope of use of different measurement modes and choose the right measurement mode.
2.The wrong measurement range was selected.
The measurement range of the multimeter usually has multiple levels, for example, the voltage measurement range can be selected from different gears such as 2V, 20V, 200V, etc. Selecting the wrong measurement range can result in measurement results that are out of range or too coarse to obtain accurate data. For example, using a voltage measurement range of 20V to measure the voltage of a 12V battery may result in inaccurate measurement results. Therefore, before making a measurement, you should choose a suitable measurement range according to the physical quantity to be measured.
3.Ignore security measures.
When measuring circuits, multimeters can involve high voltages and high currents. Beginners sometimes ignore safety measures, such as not wearing insulated gloves, turning on the power supply, etc., which can lead to hazards such as electric shock or short circuit. Therefore, it is important to understand and follow the safety operating procedures before using the multimeter to protect yourself. For example, when measuring a high-voltage circuit, you should disconnect the power supply and wait for the capacitor to discharge before making the measurement.
4.Wrong probe connection.
Incorrect probe connection of the multimeter can lead to inaccurate measurement results or damage to the measurement object. Beginners may connect the probe to the wrong electrode, or the connection is not secure, resulting in bad contact. Proper probe connection is key to ensuring accurate measurements, so you should carefully read the multimeter's instructions for the correct probe connection method. For example, when connecting a multimeter, you should pay attention to the polarity to avoid connecting the positive and negative poles in reverse.
5.Doesn't know the state of the circuit.
When measuring circuit connection issues, beginners may ignore the state of the circuit, such as whether there is a power supply, whether there is capacitor charging, etc. These factors may affect the measurement results or pose a safety risk. Therefore, before measuring, you should know the status of the circuit and take corresponding measures, such as disconnecting the power supply, discharging, etc. For example, when measuring capacitor voltage, the capacitor should be discharged first to avoid electric shock or capacitor**.
6.No calibration and calibration are performed.
Multimeters may experience measurement errors after a period of use, requiring calibration and calibration. Beginners may ignore this step, resulting in inaccurate measurements. Therefore, regular calibration and calibration of the multimeter is an important step to ensure the accuracy of the measurement. For example, a multimeter can be calibrated with a standard voltage source to ensure accurate measurements.
In conclusion, beginners should pay attention to choosing the correct measurement mode and range, following the safety operating procedures, connecting the probe correctly, understanding the circuit status, and calibrating and calibrating when using the multimeter. If in doubt, you should consult a professional technician or other experienced person for accurate measurement results and safe operation.
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