Application of point-on-wave controlled closing for temporary protective ground testing

Temporary protective grounds (TPGs) are devices utilized as a protective measure for personnel working on equipment that can be incidentally energized. As such, they need to be able to provide adequate protection and meet established standards. Previous testing methods for TPGs were performed based on a user initiated random close signal sent to a breaker that would cause a fault current on the device. This random close method yielded inconsistent test data which provided results with low repeatability. An improved point-on-wave controlled closing process is described and implemented which greatly improves the quality of the tests. The method of point-on-wave control allows for precise closing of a breaker. The consistency provided and ability to control when a breaker closes is ideal for testing. By compliance testing TPGs to recognized standards with a point-on-wave control, they can accurately be assessed for their capabilities.