Correct Wiring of Multimeter and Selection of Measuring Range
Correct wiring:
1. Connect the red test lead to the “+” polarity jack, and the black test lead to the “—” or “*” or “COM” polarity jack.
2. When measuring DC flow, pay attention to the positive and negative polarity, so as not to reverse the pointer.
3. When measuring current, the meter should be connected in series in the circuit under test; when measuring voltage, the meter should be connected in parallel at both ends of the circuit under test.
4. When measuring transistors, keep in mind that the red test lead of the multimeter is connected to the negative pole of the battery in the meter; the black test lead is connected to the positive pole of the battery in the meter.
Correct choice of measuring gear
1. When measuring voltage, the transfer switch should be placed on the corresponding voltage gear; when measuring current, the corresponding current gear should be placed, etc.
2. When selecting the current or voltage range, it is better to make the pointer be at more than two-thirds of the scale; when selecting the resistance range, it is best to make the pointer be at the middle of the scale.
3. When measuring, if you are not sure about the range of the measured value, you should first turn the switch to the corresponding maximum range, and then gradually reduce it to the appropriate range according to the degree of deflection of the pointer.
