Pay attention to the instructions when using the multimeter
(1) Before using the multimeter, "mechanical zero adjustment" should be carried out first. This entails moving the multimeter's pointer to the location of zero voltage or zero current when there is no electricity to be measured.
(2) When using the multimeter, avoid touching the test lead's metal portion with your hands. By doing this, you can ensure both the measurement's accuracy and your own safety.
(3) It is impossible to switch gears when measuring a specific amount of power; extra care should be taken when measuring high voltage or huge current. The multimeter will be harmed otherwise. If you need to change gears, unhook the test leads first, then shift gears, and measure again.
(4) To prevent inaccuracies, the multimeter must be used horizontally. At the same time, care should be taken to prevent the multimeter from being affected by the external magnetic field.
(5) The transfer switch needs to be set to the highest AC voltage gear after the multimeter has been used. The multimeter's battery should also be removed if it hasn't been used for a while to avoid the battery corroding other parts of the meter.
When using an analog multimeter, place one end of the two measuring pens into the measuring end as required, with red pointing upward (+) and black pointing downward (-), and then check to see if the pointer is in the "0" position. If not, zero adjustment is needed. The pointer should be parallel to the end line on the left side of the dial. To avoid damaging the multimeter with too much current, it is necessary to estimate the range of the current and voltage to be measured, set it to a larger gear at first, and then adjust to an appropriate gear.
The impact of the multimeter's internal resistance should be considered when taking measurements. For instance, the test leads should be connected to the circuit being tested in order to measure the voltage. Current is currently flowing through the multimeter's resistance, which has some bearing on the measured value. If different gears are used when measuring the voltage at the same location, the multimeter's internal resistance will vary, as will the degree of influence.
It is preferable to choose an internal resistance of 20k/V with DC when testing transistor electrical circuits; this value is typically marked on the multimeter's dial. Furthermore, transistor circuits frequently need to measure low voltages, such 0.1V. The chosen multimeter at this moment must have a 1V measuring range.
