1) Using a grounding rod or another suitable device to tie a system or device to the earth at the datalogger site. Such a connection is used as a sink for electrical transients and possibly damaging potentials, such as those produced by a nearby lightning strike. 2) A reference potential for analog voltage measurements. Note that most objects have a "an electrical potential" and the potential at different places on the earth ? even a few meters away ? may be different. See ground loop.
A ground circuit that has contact with the earth.
A conductor that will dissipate large electrical currents into the Earth.
A wire conductor that terminates in the earth for electrical purposes.
A metal rod, usually copper, that provides an electrical path to the earth, to prevent or reduce the risk of electric shock.
A low impedance path to earth for the purpose of discharging lightning, static, and radiated energy, and to maintain the main service entrance at earth potential.