Why does a multimeter read DC when the needle turns the other way?
1. Function of pointer multimeter
A pointer multimeter, like other multifunctional meters, can measure various data such as DC current, DC voltage, AC current, AC voltage, resistance, etc.
2. How to measure direct current
The meter head of a pointer multimeter is actually a DC current meter head. When measuring DC current, each gear is equivalent to a resistor with different resistance values connected in parallel to the meter head, which divides the current. When measuring DC voltage, a resistor with different resistance values is connected in series to the meter head for voltage reduction.
How to use a multimeter to measure
There are several steps to using a multimeter:
1. Before use, observation and mechanical zeroing are required to ensure that the pointer is on the zero mark before use.
2. Select the correct gear based on the measured data, for example, when measuring DC current, the gear should be set to DCmA. It is necessary to choose the DC gear because DC is DC and AC is AC. The specific gear needs to be estimated based on the actual measurement data.
3. The red probe should be inserted in the "+" position, and the black probe should be inserted in the "com" port. During measurement, the red probe should be at the positive pole of the device being tested, and the black probe should be at the negative pole of the device being tested (this is the focus of the problem)
Because the characteristic of direct current is that its direction does not change over time, it has a direction, and it is important to pay attention to the direction when measuring. If measured as shown in the above figure, the reverse value will be displayed.
