Electronics work by interconnections. Normally, you’d think that a potential at one point on a wire is the same everywhere. However, that is (mostly) not the case and all kinds of aspects can pop up that make the potentials differ at different locations.
Old-timers may remember connecting a printer to a computer and getting zapped by the connector when touching both computer and printer at the same time. You’d expect both ground-levels of the computer and the printer to be at the same level, but they are not (due to capacitive/inductive coupling). The problem is much wider than the printer on a computer. Any connection you make may give rise to:
- ground-loops
- common-mode couplings
- inductive/capacitive couplings
The most important in simple electronics is the ground-loop. A ground-loop is the problem where multiple paths exist for ground currents to flow. Especially when there are high- and low-current paths, then interconnections between the grounds may exhibit quite large differential voltages, due to DC-resistance of the wiring. It should be noted that multiple low-current paths may also cause immense problems.
It is easy to imaging that, if your computer is part of such a ground-loop, then it may take permanent damage. Also other electronics take damage because signal levels are not there where they are supposed to be. You have to break the ground-loop to solve the problem.
NoLoop is a galvanic isolator for both signal and power connections. NoLoop separates the in- and out-put breaking any existing of a ground-loop in that connection path.
For more detail: NoLoop – Serial and SPI isolator Breaking ground-loops with galvanic isolation
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