Powerful performance, durable and reliable – Three-Phase Pad-Mounted Transformer, the backbone of power systems!
01 General
1.1 Project Description
75 kVA pad mounted transformer was delivered to South American in 2024. The rated power of the transformer is 75 kVA with ONAN cooling. The primary voltage is 24.94/14.4kV with ±2*2.5% tapping range (NLTC), the secondary voltage is 0.208/0.12kV, they formed a vector group of YNyn0, and it is a loop feed transformer. This product has the characteristics of small size, easy installation and maintenance, low noise, low loss, anti-theft, full protection, strong overload capacity and so on. Applicable to new residential areas, green belts, parks, station hotels, construction sites, airports and other places. An independent cabinet structure is adopted, and the top of the cabinet is inclined to facilitate effective drainage. A variety of switches and protection components can be integrated, making the transformer more compact shape, more complete function, more reliable performance.
1.2 Technical Specification
75 KVA transformer specifications type and data sheet
| Delivered to | South America |
| Year | 2024 |
| Type | Pad mounted transformer |
| Standard | IEEE C57.12.00 |
| Rated Power | 75KVA |
| Frequency | 60HZ |
| Phase | 3 |
| Cooling Type | ONAN |
| Primary Voltage | 24.94GRDY/14.4 KV |
| Secondary Voltage | 0.208GrdY/0.12 KV |
| Winding Material | Aluminum |
| Angular displacement | YNyn0 |
| Impedance | 3% |
| Tap Changer | NLTC |
| Tapping Range | ±2*2.5% |
| No Load Loss | 0.08KW |
| On Load Loss | 1.27KW |
| Accessories | Standard Configuration |
1.3 Drawings
75 KVA pad mounted transformer diagram drawing and size.
02 Manufacturing
2.1 Core
| The three-phase five core column type is also called the three-phase three core column side yoke type, which is formed by adding two side yoke (no winding core) to the outside of the three-phase three core column, but the cross section and height of the upper and lower iron yoke are smaller than that of the ordinary three-phase three pillar type. This reduces the height of the entire transformer. The three-phase five-core column is compared with the three-phase core, and there are two more branch core columns on the left and right sides of the core column to become the side yoke. The windings of each voltage stage are respectively set on the middle three core columns according to the phase, and the side yoke has no winding, so that a three-phase five-core transformer is formed. |  |
2.2 Winding
 | Advantages of Wire-Wound High-Voltage Windings 1. Excellent Insulation 2. High Space Utilization 3. Good Heat Dissipation 4. Mature Manufacturing Process Advantages of Foil-Wound Low-Voltage Windings 1. Reduced Resistance Losses 2. High Current Carrying Capacity: 3. Improved Short-Circuit Strength 4. Better Power Density |
2.3 Tank
| The tank is made of stainless steel, which has good strength and durability. The steel surface is coated with an anti-corrosion coating to prevent corrosion caused by external environmental influences. An independent cabinet structure is adopted, the top of the cabinet is inclined to facilitate effective drainage, and the cabinet is also easy to install components. |  |
2.4 Final Assembly
 | 1. Winding Installation: Mount high and low voltage windings, connect leads, and ensure proper insulation. 2. Insulation and Testing: Add insulation materials and perform withstand voltage and partial discharge tests. 3. Enclosure Assembly: Place the core and windings into the casing and complete the sealing process. 4. Accessory Installation: Install essential components such as oil gauges, temperature controllers, and dehydrators. 5. Oil Filling (for Oil-Immersed Transformers): Vacuum fill the transformer oil, adjust the oil level, and ensure no air bubbles remain. |
03 Testing
1. DC resistance test.
2. Insulation resistance test.
3. Measurement of voltage ratio and vector group.
4. Separate source ac withstand voltage test.
5. Induced ac withstand voltage test.
6. Measurement no-load loss and no load current.
7. Measurement load and impedance.
8. Resistance loss and efficiency.
9. Seal test.
04 Packing and Shipping
05 Site And Summary
Thank you for your interest in our three-phase pad-mounted transformer! As a benchmark for reliable, efficient, and intelligent power distribution solutions, this product is recognized for its outstanding performance, robust design, and exceptional energy efficiency, earning the trust of customers across various industries. Whether for residential, commercial, or industrial applications, we are committed to providing customized services to help you build a stable and efficient power system. We look forward to working with you to create a bright future for intelligent power solutions! For more information, please feel free to contact us, and we will be delighted to assist you!
