What kinds of conditions can burn the multimeter
When the multimeter is measuring high voltage, forgetting to switch gears will burn the multimeter. For example, use the resistance gear to measure 220v voltage. Some multimeters have anti-burning protection function, so we must first select the gear range when using the multimeter. After measuring, don’t just pick it up and use it blindly. When not in use, we must develop the multimeter to the highest voltage level, or to the off level, in case we forget to adjust the level and burn out the multimeter, and do not charge the components when measuring To measure, especially the power supply line above 220v, the power must be cut off when measuring the connection of the line.
As long as the multimeter can be used normally according to the requirements, the service life is quite long. My MF47 was used for more than 30 years in 1988. (Product number 8884454) To use it, you must develop good habits, such as measuring voltage without knowing the voltage How much should be put in the highest gear first, and the gear must be checked before touching the measuring point every time, so as to prevent the voltage from being measured just after the on-off measurement, and the ammeter is still in the ohm gear. In short, develop good usage habits. Life is very long.
There are several reasons for the multimeter to burn. First, it is very dangerous to switch to the resistance gear to measure AC, and the meter will burn immediately. Second, when measuring AC voltage, switch to the low voltage gear to measure high voltage, and the watch will burn at this time. The fourth is to measure the current in series with the load and the multimeter can only measure a small current, so if it is not connected in series, it will burn the meter. Even if it is connected in series, it will burn the meter if the current exceeds the current. However, with the advancement of technology, some multimeters have reliable protection. device, reducing the possibility of burning the meter
1. Low voltage block to measure high voltage.
2. Small current block to measure large current.
3. The current block measures the voltage.
4. Resistance to measure voltage and current.
Today's multimeters have protection functions. There are three fuses in the back cover, which are voltage and current resistors. The protection fuse is broken due to misuse. If it is a pointer, it may burn the dial or hands. Because the instantaneous voltage and current were too large, the fuse did not have time to break. A bad fuse can only be regarded as a minor fault, and a bad circuit board can only be regarded as a burnt out.
