How to use a multimeter to measure current
When measuring DC voltage, set one switch of the multimeter to the DC current gear, and the other switch to the appropriate range of 50uA to 500mA. The range selection and reading method of the current are the same as those of the voltage. At this time, you should pay attention to the positive and negative polarities. If the test leads are reversed, the hands will be reversed. If you do not know the positive and negative polarity of the circuit, you can set the range of the Wantian meter to the maximum range, quickly test it on the circuit under test, and see how the pen needle is deflected, you can judge the positive and negative polarity. There is no positive or negative. When measuring, the circuit must be disconnected first, and then the multimeter is connected in series to the circuit under test in the direction of current from "+" to "-", that is, the current flows in from the red test lead and flows out from the black test lead.
When measuring DC current, if the multimeter is connected in parallel with the load by mistake, the internal resistance of the meter head is very small, which will cause a short circuit to burn the meter. The reading method is as follows: actual value = indicated value × range / full deviation
