How Do You Find a Ground Loop

Conductors connected to ground are found in most cables that connect to a data logger. These include sensors cables, communication cables, and power cables. Any time one of these cables connects to the same two endpoints as another cable, a ground loop is formed.

How do you fix a ground loop problem?

1. Remove one of the ground paths, thus converting the system to a single point ground.
2. Isolate one of the ground paths with an isolation transformer, common mode choke, optical coupler, balanced circuitry, or frequency selective grounding.

What is a ground loop and why is it bad?

Ground loops are a potential cause of noise interference on the PCB. If one component on the loop is noisy and the return current flows through shared ground connectors, this noisy component is then the source for an introduction of noise to other components on the loop.