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(1) All field equipment is not grounded, so that all of the loop is only one ground, can not form a loop, this method seems simple, but the practical application is often difficult to achieve, because some devices require must be grounded in order to ensure accuracy or personal safety, some devices may have been due to the long-term corrosion and wear or weather influence after the formation of new ground.
(2) so that the potential of two of the same ground, but because of the resistance of the ground affected by many factors, geological conditions and climate change, in fact, this approach in practice can not be fully able to do.
(3) used in various aspects of the process of signal isolation, disconnection of the loop, without affecting the normal transmission of signals, thus completely solve ground loop problems.