When a ground fault occurs, its presence is detected by an insulation monitoring device (IMD) such as an iso685‑D‑P (“P” stands for pulse), which signals that there is a fault, begins to send an identifiable current signal into the power system, and activates the EDS device. The EDS is a multichannel detector to which measuring current transformers (CTs) are connected. The CTs monitor feeders or loads in a zero-sequence fashion (all load conductors pass through the CT window) and are sensitive to the locator pulse, which only flows to the fault. The EDS reports the fault location to the IMD, which displays the information on its LCD and communications interface. This all occurs without the need for operator intervention. Watch the video on the right to learn more about how the EDS system works.

The EDS can be used in nearly every application imaginable. Commonly, the EDS is used to locate ground faults in food processing or manufacturing facilities. By detecting and addressing the fault early, it can prevent conditions that would cause the ground fault breaker to trip. The fault location can take place far upstream (by the transformer) or all the way downstream (at the load level).

Another common application is using the EDS to locate faults on solar or energy storage installations. These faults can be located to the string, combiner, battery, or inverter level. The same technology can be applied to locating faults on processing equipment on a land or sea-based oil vessel. Bender has also applied numerous EDS units to sensitive applications, such as nuclear control process equipment or hospital isolated power panels.