Earthing / Grounding Transformer
Earthing transformers are designed to create a neutral point in a three-phase system, enabling neutral earthing. The earthing can be achieved through an arc-suppression reactor, a neutral earthing reactor, a resistor, or directly within the transformer. These transformers are typically oil-immersed and suitable for outdoor installation. In cases where a separate reactor is connected between the earth transformer’s neutral and the ground, both the reactor and the transformer can be housed in the same tank.
Neutral earthing transformers are commonly used in three-phase systems that lack a neutral point and earth fault protection. They are available with ONAN (Oil Natural Air Natural) or ONAF (Oil Natural Air Forced) cooling configurations. The range supports systems up to 33 kV and can be customized to meet specific site requirements.
Standard Features
• Meets or exceeds current IEC, WAPDA, K-Electric, or any other standards required by the customer
• 50 Hz operation
• Mild Steel (MS) (sealed type) tank (optional corrugated tank) with welded lifting lugs, support angles, and base channels for pole mounting
• Mild steel MS Undercarriage with roller wheels (above 100KVA)
• Oil level gauge
• Oil filling plug
• Powder coating on state of the art automatic plant provides superior corrosion protection and is aesthetically pleasing to the eye
• Top cover mounted porcelain bushings
• Tin-plated brass terminals for connection to copper/aluminum conductors
• Tank ground provision through earthing terminal
• Insulated cover for wildlife protection
• Engraved nameplate (rating and diagram)
• Insulating oil as per IEC60296 standard
• KVA rating on transformer
• Protection from lightning through arcing horns (outdoor transformer)
Test
All transformers are tested in strict accordance with WAPDA P10 standard following from IEC with test reports available by serial number
Routine Tests
• Polarity and Phase relation
• Resistance
• Power frequency test
• Megger test