The ground window concept

Voltage differences in earthing systems, both within and between equipotential zones, can be problematic for communications, information technology, and control systems. Surges from atmospheric conditions, high voltage switching operations, etc., can damage equipment. This is especially true if the installation, and in particular the earthing provisions affecting both power wiring systems, and cabling for sensitive electronic systems, are not considered at the design stage. The concept of the "Ground Window" is a useful design tool for avoiding such issues. In addition, the concept has a place in analysing existing installations exhibiting behaviour where "earthing problems" are suspected.