Innovative technology, quality power -- three-phase pad-mounted transformer, driving sustainable development!
01 General
1.1 Project Description
1000 kVA pad mounted transformer was delivered to America in 2024. The rated power of the transformer is 1000 kVA with ONAN cooling. The primary voltage is 22.86GrdY/13.2kV with ±2*2.5% tapping range (NLTC), the secondary voltage is 0.48/0.277kV, they formed a vector group of YNyn0, and it is a loop feed and dead front transformer.
The high-voltage terminals of this three phase pad mounted transformer are equipped with feed-thru insert, designed to connect elbow cable plugs or fully insulated elbow surge arresters. This design completely seals the live parts within the insulating material, forming a fully insulated structure. The terminal surface remains non-conductive (at ground potential), ensuring personnel safety. In emergencies, the cable plug can be hot-swapped under full transformer load, thereby serving as a load switch if needed.
Additionally, live-line indicators or fault indicators can be installed on the cable plugs based on operational requirements to monitor system status or locate faults. On the high-voltage front chamber wall of the transformer, near the high-voltage bushing, a wall-mounted fixture is welded to secure optional stand-off insulated bushing connectors. When the cable plug is removed while energized, it can be immediately inserted into the stand-off bushing connector to ensure operational safety and system stability.
1.2 Technical Specification
1000 KVA transformer specifications type and data sheet
| Delivered to | America |
| Year | 2024 |
| Type | Pad mounted transformer |
| Standard | IEEE Std C57.12.34-2022 |
| Rated Power | 1000KVA |
| Frequency | 60HZ |
| Phase | 3 |
| Feed | Loop |
| Front | Dead |
| Cooling Type | ONAN |
| Primary Voltage | 22.86GRDY/13.2 KV |
| Secondary Voltage | 0.48/0.277 KV |
| Winding Material | Aluminum |
| Angular displacement | YNyn0 |
| Impedance | 5.75%(±7.5%) |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5% |
| No Load Loss | 1.095KW |
| On Load Loss | 7.855KW |
| Accessories | Standard Configuration |
1.3 Drawings
1000 KVA pad mounted transformer diagram drawing and size.
02 Pad Mounted Transformer Accessories
2.1 Bay-O-Net Fuse
| The transformer uses a Bay-O-Net expulsion fuse on the primary side, providing basic overcurrent protection that fits well with everyday operating conditions. It clears typical faults within its capability and allows simple field replacement when needed. Working together with the internal current-limit fuse, it forms a coordinated protection setup that maintains reliable operation under normal and moderately high fault levels. |  |
2.2 Current Limit Fuse
 | An internal current-limit fuse is installed to handle high-energy primary faults that exceed the interrupting range of the Bay-O-Net fuse. It responds rapidly, limiting fault current and reducing thermal stress on the windings. By operating in series with the expulsion fuse, the CL fuse provides a second protective layer, ensuring the transformer can withstand severe fault conditions while maintaining system safety and long-term durability. |
2.3 25 KV Elbow Arrester
| The transformer is equipped with a 25 kV elbow-type surge arrester connected through a loadbreak interface. It provides continuous protection against lightning surges and switching transients that may appear on the primary line. The arrester helps keep the insulation system within safe limits, supports stable operation in typical distribution environments, and maintains the overall reliability expected from dead-front pad-mounted equipment. |  |
03 Testing
| No. | Test Item |
| 1 | Resistance Measurements |
| 2 | Ratio Tests |
| 3 | phase-relation tests |
| 4 | No-load losses and excitation current |
| 5 | Load losses impedance voltage and efficiency |
| 6 | Applied Voltage Test |
| 7 | Induced Voltage Withstand Test |
| 8 | Leakage Test |
| 9 | Insulation Resistance Measurement |
| 10 | Oil Test |
04 Packing and Shipping
05 Site And Summary
In conclusion, our three-phase pad-mounted transformers stand at the forefront of reliable and efficient power distribution solutions. Designed with advanced technology and superior craftsmanship, these transformers offer unmatched performance and safety for various applications. Whether for commercial, industrial, or utility needs, our transformers ensure stable electricity delivery, enhance operational efficiency, and promote sustainability. Trust in our commitment to quality and innovation to power your future effectively. Contact us today to learn more about how our three-phase pad-mounted transformers can meet your energy solutions needs!
