To avoid damage to the multimeter, please note the following.
1. In most cases, the damage of the digital multimeter is caused by the wrong measurement gear. For example, when measuring AC mains, the measurement gear is selected to be placed on the electric block. In this case, once the meter pen touches the mains, it can be caused in an instant. The internal components of the multimeter are damaged. Therefore, be sure to check whether the measurement gear is correct before using the multimeter to measure. After use, set the measurement selection to AC 750V or DC 1000V, so that no matter what parameter is wrongly measured in the next measurement, it will not cause damage to the digital multimeter.
2. The damage of some digital multimeters is caused by the measured voltage and current exceeding the range. If the mains is measured at the AC 20V range, it is easy to cause damage to the AC amplifier circuit of the digital multimeter, and the multimeter loses the AC measurement function. When measuring DC voltage, the measured voltage exceeds the measurement range, which is also likely to cause circuit failure in the meter. When measuring the current, if the actual current value exceeds the range, it will generally only cause the fuse in the multimeter to blow, and no other damage will be caused. Therefore, when measuring voltage parameters, if you do not know the approximate range of the measured voltage, you should first set the measurement gear to the highest gear, and then change the gear to measure the value to obtain a more accurate value. If the voltage value to be measured is far beyond the maximum range that the multimeter can measure, a high-resistance measurement lead should be provided.
3. The upper limit range of DC voltage of most digital multimeters is 1000V, and the upper limit range of AC voltage is 750V. Therefore, the highest value of the measured voltage is below the upper limit range of the multimeter, which generally will not damage the multimeter. If the upper range of the multimeter is exceeded, the multimeter is likely to be damaged.
4. Do not measure voltage in current, resistance, diode and buzzer. When the instrument is under test, it is not allowed to rotate the function switch, especially at high voltage and high current.
5. If you use the multimeter to check the quality of the components or measure the resistance of the components in the circuit, it is not allowed to be charged in the circuit, because the multimeter is powered by the internal battery of the multimeter. It will affect the measurement accuracy. If the multimeter's electrical barrier is insured, it is easy to damage the equivalent resistance of the electrical barrier.
6. When the battery symbol appears on the screen, it means the battery is insufficient and the battery should be replaced. After each measurement, the meter should be turned off. Regardless of use or storage, it is strictly forbidden to get wet and water.
To avoid possible electrical shock and personal injury, follow these rules:
1. Do not use damaged instruments. Before using the instrument, please check the case of the instrument and pay attention to the insulation near the connection socket.
2. Check the test leads to see if there is damaged insulation or exposed metal, check the continuity of the test leads, and replace the damaged test leads before using the meter.
3. When the operation is abnormal, please do not use the instrument, so the protection may be damaged. When in doubt, send the meter for overhaul.
4. Please do not use the instrument near explosive gas, steam or dust.
5. Please do not input more than the rated voltage marked on the meter between any two terminals or between any terminal and the ground.
6. Before use, please use the meter to measure a known voltage to verify the meter.
7. When measuring current, please turn off the power of the line before the instrument is connected to the line.
8. When overhauling the instrument, please only use the marked replacement parts.
9. Please pay special attention when measuring the average value of AC voltage of 30V, the peak value of 42V or the DC voltage of 60V or more, because such voltages will cause electric shock hazards.
10. When using the test pen, please keep your fingers behind the hand of the test pen.
11. When measuring, please connect the public test lead (black test lead) first and then the charged test lead (red test lead); when disconnecting, please disconnect the charged test lead first, and then disconnect the public test lead.
12. When opening the battery compartment, please remove all test leads from the meter.
13. Do not use the meter when the battery compartment or the meter casing is not tightly closed or loosened.
14. When the battery low voltage instruction symbol “ ” appears, please replace the battery as soon as possible to avoid possible electric shock or personal injury caused by misreading.
15. Please do not use a multimeter to measure voltages other than the CAT classification level indicated by the multimeter.
