1. Confirm before measurement, so as not to burn the meter due to wrong function (such as measuring voltage with current gear);
2. Do not exceed the range (for example, if the current range of many multimeters exceeds the current range, the fuse or multimeter will burn, and the same voltage measurement should not exceed 1000);
3. The desktop multimeter should also pay attention to the input voltage of the power supply, and it must be consistent before it can be powered on.
