Steps to measure DC current with a multimeter:
1, mechanical zeroing:
As with resistance and voltage measurement, the multimeter should be mechanically zeroed before use. Mechanical zeroing method with the previous resistance measurement, voltage measurement of mechanical zeroing operation. This will not be repeated here, the general use of the multimeter does not need to be mechanical zeroing every time.
2, select the range:
According to the circuit to be measured in the power supply current roughly estimate the size of the measured DC current, select the range. If you are not sure about the size of the current, you should first use the highest current file (500mA file) to measure, and then gradually switch to a lower current file until you find a suitable current file (standard with the measured voltage).
3. Measurement method:
When using the multimeter current block to measure the current, the multimeter should be connected in series in the circuit to be measured, because only the series connection can make the current flowing through the ammeter and the measured branch current the same. When measuring, the measured branch circuit should be disconnected, and the red and black pens of the multimeter should be connected in series between the two points that are disconnected. Especially note that the ammeter can not be connected in parallel in the circuit under test, it is very dangerous to do so, it is very easy to make the multimeter burnt. At the same time, pay attention to the polarity of the red and black meter stick, the red meter stick should be connected to the current inflow end of the circuit under test, the black meter stick is connected to the current outflow end of the circuit under test (the same as the DC voltage polarity selection).
4, the correct use of scale and readings.
Multimeter DC current measurement dial scale with the same choice of voltage measurement, are the first (the first scale to the right of the mA symbol). Other scale characteristics, reading method with the same voltage measurement.
If the measured current is greater than 500mA, you can choose 5A gear. Operation method: Set the conversion switch at 500mA range, take out the red meter stick from the original "+" jack, and insert it into the jack marked with 5A in the lower right corner of the multimeter to measure the large current below 5A.
