Shown on this slide are two independent circuits with their own grounds and supplies. If they are connected directly, a ground potential difference is created. This ground potential difference has a ground loop signal path denoted by the brown arrow. Noise sources can come out of the ground as larger equipment dumps their current, causing the ground floor to change. As data is transmitted from the left circuit to the right, it will diminish the amount of data that is received by the second circuit, as indicated by the signal and return path in the blue arrow. However, if an isolator is added, the ground loop is broken up and data can be extracted from the left circuit and given to the right circuit. The ground potential still exists, but the isolator is robust enough to withstand the large voltage difference.