How to use a digital multimeter?

(1) Use the resistance block. When measuring resistance with a digital multimeter, there is no need to adjust the zero at any position. Plug the red test lead into the "v/Ω" jack, plug the black test lead into the "COM" jack, and turn the function switch to the corresponding range of the ohm range. When there is no input (such as an open circuit), the display shows "1". If the measured resistance exceeds the maximum value of the selected range, the display shows "1" and a higher range should be selected. For resistances greater than 1MQ, it takes a few seconds for the reading to stabilize. This is normal.

(2) Use the DC voltage range. Plug the red test lead into the "V/Ω" jack, the black test lead into the "COM" jack, and turn the function conversion switch to the range corresponding to the DC voltage being measured (the range selection is the same as that of the pointer multimeter). When the polarity of the measured voltage is reversed, "1" will be displayed in front of the value. At this time, there is no need to change the test leads and re-measure. If only "1" is displayed, it means that the measured voltage exceeds the maximum value of the range, and a larger range should be selected. Note: Do not measure voltages above 1kV, otherwise it is easy to damage the internal circuit of the multimeter.

(3) Use the AC voltage range. Plug the red test lead into the "V/Ω" jack, plug the black test lead into the "COM" jack, and turn the function conversion switch to the range corresponding to the AC voltage being measured.
The other methods are basically the same as those for measuring DC voltage. Note: Do not measure voltages above 700V, otherwise the internal circuit of the multimeter may be damaged.

(4) Use of DC current range. Plug the black test lead into the "COM" jack. When the maximum value of the measured current does not exceed 200mA, plug the red test lead into the "mA" jack
. When the maximum value of the measured current exceeds 200mA, plug the red test lead into the "10A" jack. Turn the function conversion switch to the range corresponding to the DC current to be measured, connect the two test leads in series in the circuit to be measured, and then the measurement can be carried out.

(5) Use the AC current range. Turn the function conversion switch to the corresponding range of AC current. The other methods are basically the same as those for measuring DC current.

(6) Use the diode position. Turn the function conversion switch to the position marked with the diode symbol, and connect the red and black test leads to the two ends of the diode respectively. If "1" (overflow) is displayed, it means that the reverse voltage drop of the diode is measured. Exchange the test leads and measure again. The value displayed at this time is the forward voltage drop value of the diode (in V). The end connected to the red test lead is the positive pole, and the other end is the negative pole.