Neutral earthing resistance is manufactured for the purpose of providing additional security restricting earth fault currents of the power distribution systems. High fault currents (10.000 - 20.000 A) that in case of stage- ground malfunction in the direct grounded systems can damage to generators and transformers which connect the system significantly during the period until protection relays work.
When the neutral earthing resistance is connected in between the neutral point and ground, grid line to earth voltage appears at a ground failure around the substation center and fault current is limited to level indicated previously ( low enough not to damage the system, high enough to feel by protection relays) by the resistance.
Also, transformer neutral earthing resistance provides the security of system and personnel limiting (up to the 2-6 times of grid voltage) the temporary voltage rises that could occur at the arc type (very short period of time) stage-ground malfunctions distributing the emerged energy onto itself.
System Features
Units of stainless steel resistance
2 mm thick hot-dip galvanized dkp sheet metal cabinet
high-level protection against corrosion with 70 micron thick polyester electrostatic powder coating with epoxy-based
Internal current transformer (EN 60044-1)
High thermal capacity absorbed high voltages
Cast lifting eyes which are manufactured for the neutral earthing resistance because of the dependable carriage
Structure which is substantial against the shock impacts
