What is Ground?
A ground is a direct electrical connection to the earth, a connection to a particular point in an electrical or electronic circuit, or an indirect connection that operates as the result of capacitance between wireless equipment and the earth or a large mass of conductive material.
Why is Ground Important?
Electrical grounding is important because it provides a reference voltage level (called zero potential or ground potential) against which all other voltages in a system are established and measured. An effective electrical ground connection also minimizes the susceptibility of equipment to interference, reduces the risk of equipment damage due to lightning, eliminates electrostatic buildup that can damage system components, and helps protect personnel who service and repair electrical, electronic, and computer systems. In effect, an electrical ground drains away any unwanted buildup of electrical charge. When a point is connected to a good ground, that point tends to stay at a constant voltage, regardless of what happens elsewhere in the circuit or system. The earth, which forms the ultimate ground, has the ability to absorb or dissipate an unlimited amount of electrical charge.
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