How to measure DC current with a multimeter
One, DC current measurement method
1. Insert the black test lead into the COM jack. When measuring the maximum current of 200mA, insert the red test lead into the mA jack. When measuring the maximum current of 20A, insert the red test lead into the 20A jack.
2. Set the function switch to DC current block A-appropriate range.
3. Connect the test leads in series to the load to be tested, keep it stable, and then read. If it is displayed as "1.", then the range should be increased. If "-" appears on the left side of the value, it means that the current flows from the black test lead into the multimeter.
two, operation tips
1. Select the DC current gear for the gear position. When the current range is not known, it should be selected from the maximum range.
2. Pay attention to the current direction, that is, the red test lead is connected to the positive pole of the power supply (or high potential), and the black test lead is connected to the negative pole of the power supply (or low potential).
3. The meter should be connected in series in the circuit of the measured current.
4. The method of measuring AC current is similar to that of measuring DC current, except that there is no polarity limit.
Three, DC current measurement steps
Step 1: Rotate the gear of the multimeter to the range of DC current 200mA.
Step 2: Close S1 on the physical circuit.
Step 3: Connect the red test lead to 1 and the black test lead to 2, observe the readings, and the measured current between points 1 and 2 in the branch circuit is 20mA.
four, matters needing attention
1. If you do not know the measured current range before use, set the function switch to the maximum range and gradually decrease it.
2. If it is displayed as "1.", it means that the range is too small, and the function switch should be set to a higher range.
3. It means that the maximum input current is 200mA. Excessive current will burn out the fuse, which should be replaced again. The 20A range has no fuse protection, and the measurement cannot exceed 15 seconds.
4. The measurement method of AC current is the same as that of DC, but the gear should be set to AC gear A~. After the current measurement is completed, the red pen should be inserted back into the "VΩ" hole. If you forget this step and directly measure the voltage, the indicator Or the power supply will be scrapped, please operate with caution!
