Long DC power cables, used in both permanent and temporary installations such as railway tunnels, cranes, overhead cranes, road and construction sites, DC charging systems, or subsea installations, are exposed to wear over time. The DDEA earth fault relay provides reliable monitoring of potential earth faults in DC networks, ensuring optimal protection for both equipment and personnel.

Operation
By using an artificial ground reference, the DDEA detects leakage currents from the positive or negative pole to earth. These leakage currents may be caused by direct short circuits or damaged insulation. Insulation damage can lead to dangerous earth faults that are often detected only when it is too late. Permanent earth fault monitoring with the DDEA helps prevent downtime and safety issues.