The Use of a Multimeter (1)

The use of a multimeter (1)
1. Select the appropriate magnification. When measuring resistance with an ohmmeter, an appropriate magnification should be selected so that the pointer indicates near the median value. It is best not to use the left third of the scale, which is poorly dense.
2. Zero adjustment before use.
3. Do not measure with electricity.
4. The resistance under test cannot have parallel branches.
5. When measuring the equivalent resistance of polar components such as transistors and electrolytic capacitors, you must pay attention to the polarities of the two pens.
6. When measuring the equivalent resistance of the nonlinear element with the ohm stop of different magnifications of the multimeter, the measured resistance value is not the same. This is because the median resistance and full-scale current of each gear are different. In a mechanical watch, the smaller the magnification, the smaller the measured resistance.
7. Rotate the knob of the multimeter to the position where the diode identifier is located, and then short-circuit the two test leads, you will hear a buzzer sound, which indicates that the gear can be used normally, and the resistance between the two test leads can be determined. Zero, which is often used in life to measure whether there is an open circuit in the circuit, and whether the devices are electrically connected together.
8. Since this gear is a diode gear, we can use this gear to measure the diode voltage drop. When measuring, put the red test lead on the anode of the diode and the black test lead on the cathode of the diode, and the pressure can be directly displayed on the display screen. Drop the value. In addition, this file can also be used to determine whether the diode is a silicon tube or a germanium tube, and whether the diode is damaged.