Neutral Earthing Resistors

Neutral Earthing Resistors, also known as Neutral Grounding Resistors, are used worldwide to ensure proper treatment of single phase faults against ground. They are used in distribution networks and for generator grounding as well. In many cases, the resistor is connected between the neutral point of the network and ground. If no neutral point exists it is also common to install a zig-zag transformer in the grounding system to make an artificial neutral point for the resistor. Inside the cubicle for the active part of the resistor other equipment like switches, instrument transformers, monitoring systems etc. can be placed. Many variations and combinations are possible – that is why almost all of the grounding products require new engineering for the individual design.

NER for Railway supply
NER for Railway supply

Our design engineers will work with you to ensure tailor made solutions with optimal technical data and economic design are arrived at. To date our resistors range from about 200V to 130kV network voltage. They can have short time or continuous operation. The most common insulation material is air but oil immersed resistors for 123 kV network voltage have also been manufactured. The oil immersed resistors were manufactured with a fully vacuum proven tank and conservator and could withstand full test voltage according to IEC and network voltage.

Our Neutral Earthing Resistors are manufactured using stainless steel for both the active part and the enclosure as standard. Various grades of stainless steel may be proposed depending upon each customer’s site conditions and requirements. The grade of material chosen for the active part results in different behaviours and this is carefully considered by our design engineers. In order to ensure that optimal solutions are proposed, special optimisation algorithms have been incorporated into our design software. This gives our design engineers a powerful tool to find the optimal design and allows an increasing automation and improvement of the engineering process.

The presence of salt and heavy industrial pollution at the customer’s site will also affect the engineer’s decision as to which material should be proposed. We encourage our customers to engage in detailed discussion with our engineers to ensure that all aspects of the technical specification are considered and understood prior to manufacture of the final product.

Only the best quality components are used in the manufacturing process. The factory is operated with the highest level of cleanliness and attention to detail. Stringent quality controls are in place. Testing is conducted onsite in a modern high-voltage test laboratory. All these factors ensure that production is arrived at with the highest degree of flexibility without compromising the speed of completion and delivery.

Chase Power have supplied Neutral Earthing Resistors to a broad range of projects including utility, airport, power station, substation, wind farm, desalination, sugar, aluminium, gold and other mining applications. Our power resistors are in operation throughout Australia, New Zealand, Indonesia and the Philippines.

110 kV-Oil resistor with taps (left)
110 kV-Oil resistor with taps (left)
IP54 Neutral Earthing Resistors 22kV, 500A, 10 Sec with Neutral Bar and Sensor Boxes for Airport Upgrade project
IP54 Neutral Earthing Resistors 22kV, 500A, 10 Sec with Neutral Bar and Sensor Boxes for Airport Upgrade project

Contact us to discuss your neutral earthing resistor requirements or to request a quotation.

We also supply resistors for a variety of other applications:

  • Harmonic Filters
  • Load Banks
  • Motor Control
  • Industrial Heating
  • Dynamic Braking
  • Electrolytic Starters