DC earth fault function available on NASN DC power supply

DC earth fault relays work by continuously monitoring the current flowing through the electrical system. When an earth fault occurs, the current flowing through the fault will be much higher than normal, and the relay will detect this increase in current.

NASN DC power supply system with MC700 has built in DC Earth Fault Relay. 

lf one part of the DC system touches the ground,it's not a big deal. But if both parts touch the ground,it can cause a short circuit and the breaker will open to stop the flow of electricity.

To prevent this from happening, we use a DC earth fault relay. lt can detect when one part of the DC system touches the ground and let us know that there's a problem that needs to be fixed right away.

The way it works is by connecting the DC system to the ground through two equal resistances. These resistances are chosen so that only a tiny amount of current flows between the DC terminals.

Under normal conditions, when there's no problem,the voltage between the positive and negative terminals to the ground is the same. But if there's an earth fault, it creates a parallel path for the current to flow and changes the voltage.

This causes current to flow through the relay and triggers it to let us know there's a problem.