NEUTRAL GROUNDING / EARTHING RESISTORS
NGR / NER / NGT FUNCTION
The NGR main purpose is to limit the earth fault current during a ground fault to a value which does not damage the primary equipment, but yet high enough to operate the protection relays to clear the fault.
We design, manufacture, test and deliver Neutral Grounding / Earthing Resistors for voltages levels between 3.3kV and 36kV with a wide range of resistor values.
For bigger generators we also design and deliver complete grounding transformer solutions (NGT) with single phase transformers and secondary resistor.
NGRs are typically designed for a duty cycle of a few seconds per hour.
NGR / NER / NGT DESIGN
We focus on top quality to guarantee save operation and long life time. All our NGRs are of compact design with one MV compartment
Resistors are made of stainless steel grids
- Precision ceramic insulators for high temperature withstand
- Enclosures of electro galvanized steel
- Frames are hot dip galvanized, or complete stainless steel enclosures
- The Enclosure has typically IP43 or IP54 protection for indoor or out-door installation
- Separate low voltage compartment for all secondary instruments
All components are installed within the enclosure and therefore no additional site works are required for
» external disconnector installations
» external CT installations
NGR / NER / NGT OPTIONS
In addition we have options to provide, as it may be required from project to project
Our inspection and test procedures (ITP) are carefully designed to proof the required design, quantities, functionalities and quality of the final product. Tests are performed based on customer approved drawings. Internal tests are 100% full-tests.