Potential reference point (i.e. zero potential point): select a point A as the potential reference point in the circuit, that is, specify that the potential of the point is zero, and the potential reference point is usually marked with the symbol "∨" in the circuit.
Selecting a point A in the circuit as the potential reference point means that the potential of the point is specified as zero, that is U A= 0。 The selection method of potential reference point is:
In electronic circuits, a specific common line or enclosure is often selected as the potential reference point.
