Question

What is a ground loop?

Answer

The ANSI/IEEE dictionary calls it "potentially detrimental loop formed when two or more points in an electrical system normally at ground potential are connected by a conducting path such that either points are not at the same ground potential."


What does this mean?

It creates a pathway for current to flow. If one has a process control that works on a 4-20 ma signal, the added current from a ground loop could throw the reading off. This event can be catastrophic for some processes.


The two main methods of elimination are:

1. Eliminate ground loops (which may not be possible because some control and instrumentation equipment require ground as a reference.)
   
2. Signal isolation.

Each process or control system is different; it's always a case-by-case basis if it will be affected by ground loops.

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FAQ Subcategory: None

This item was last updated on 2021-02-10
Document ID: 873

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