What is the minimum size of pipe that can be used as a grounding electrode?

The minimum size of pipe that can be used as a grounding electrode is indeed 3/4 inch. This size is specified in the National Electrical Code (NEC), which outlines the requirements for grounding electrodes to ensure safety and effective grounding. A grounding electrode needs to provide a reliable connection to the earth to dissipate fault currents and other unwanted electrical energy. A 3/4 inch pipe has sufficient surface area and conductivity to serve its purpose effectively.

Using smaller sizes, such as 1/2 inch, may not meet the performance requirements for grounding, as they may not be adequate in terms of surface area to provide a low-resistance path to ground. Larger sizes like 1 inch or 1 1/2 inch, while effective, exceed the minimum requirement and are typically not necessary unless specified for certain applications or conditions. Thus, 3/4 inch is the minimum size that ensures proper grounding electrode effectiveness while also adhering to the standards set forth in electrical codes.