630kVA Oil Immersed Transformer
- Primary Voltage Ratings 34.5-19.92/13.8-7.957/13.2-7.62/12.47-7.2, 24.94, 26.25, 33 or others
- Secondary Voltage Ratings 480/277V, 400/230V, 380/220V or customized
- H.V. Tap Range ± 2×2.5% HV taps or others
- Type Oil immersed distribution transformer
- BIL 30/95kV
- Standards IEEE, ANSI, NEMA, IEC, GB
- Application Power Distribution Networks, Industrial Applications, Infrastructure & Public Utilities
- Power Rating 630kVA
- Certificate UL, CESI, CE
- Cooling Method ONAN, ONAN/ONAF, KNAN, KNAN/KNAF
- Oil Mineral Oil or FR3
- Opeartion Step Down & Step Up
Technical Specifications
Technical Specifications | ||
Rated Power | 630 kVA | |
Rating Primary Voltage | 2.4 - 34.5kV | |
Secondary Voltage | 480/277V 400/230V 380/220V Customized |
|
Frequency | 50/60Hz | |
Vector Group | Dyn11, Yyn0, Dyn5 | |
Winding Material | Aluminum/Copper | |
Efficiency | As IEEE, Doe 2016, CAS Std or Customized | |
Impedance Voltage | Nominal 2% or Customized 1.1 - 5.75% | |
Altitude | ≤1,000m or Customized | |
Color | ANSI 70 Light gray/Munsell 7GY3.29/1.5 or customized, etc | |
Tank material | Mild Steel, 304 Stainless Steel | |
Insulating Oil Weight | 625 kg | |
Total Weight | 3000 kg | |
Outline Dimensions(L×W×H)in. | 2250 × 1350 × 2250(mm) |
HV Bushing |
LV Bushing |
Tap changer |
Oil level gauge |
Oil temperature indicator |
Pressure relief device |
Pressure vacuum gauge |
Lifting hook for complete transformer |
Name plate |
Radiators |
Oil upper filtering valve |
Oil drain valve with 3/8" sampler |
Customization Optional
Packing and Shipping
For cross-border transportation, the transformer will be transported by container shipping or special cargo ships (for super-large transformers). For goods that require a longer transportation time, bulk transportation is used. The loading and unloading of the transformer are operated by a professional lifting team, using equipment such as hooks and slings to lift it from a fixed point to ensure that no damage is caused to the equipment during operation.
All documents required for export, such as packing lists, commercial invoices, bills of lading, test reports, certificates of origin, etc., will be prepared in advance and provided with the goods.
The outside of the package is marked with clear unloading instructions, such as "fragile", "handle with care", "keep upright" and other warnings to ensure safety during transportation and unloading. Detailed installation instructions and operating manuals are provided to help customers quickly and correctly complete the installation and commissioning of the transformer.
Through the above professional packaging and transportation solutions, we ensure that the NPC ELECTRIC 630kVA oil-immersed transformer can be fully protected during transportation, arrive at the destination smoothly, and maintain the best working condition.


Manufacturer Test

Progress Test
During the production process, NPC ELECTRIC's 630kVA oil-immersed transformers are tested in strict accordance with international standards. First, the core and windings of the transformer undergo rigorous electrical performance tests to ensure that they meet the design requirements. Subsequently, the oil-immersed transformer is subjected to a high-voltage test to test its withstand voltage and insulation performance. After the transformer is assembled, a load test is carried out to ensure stable operation under different loads. Finally, a temperature rise test is carried out to verify its temperature control ability during long-term operation to ensure that the product quality meets customer requirements and industry standards.

Design Tests
All transformer will be test after finished the production, test items as below:
♦ Insulation Power Factor
♦ Ratio, Polarity, and Phase Relation
♦ Winding Resistance
♦ Impulse Tests
♦ On load Loss Test
♦ No Load Loss Test
♦ Leak Test
♦ DC Insulation Resistance Test
♦ Transformer Turns Ratio/TTR (All Tap Voltages)
♦ Impedance Voltage & Load Loss (Rated Voltage)
♦ Polarity, 1-Ph / Phase Relation, 3-Ph (Rated Voltage)
♦ Excitation & No-Load Loss (Rated Voltage)
♦ Applied Voltage
♦ Induced Voltage
♦ Lightning Impulse
♦ Insulation Resistance (Rated Voltage)
♦ Temperature Rise
♦ Dielectric Withstand (Hipot)

Transformer Factory Acceptance Test
Before the transformer leaves the factory, NPC ELECTRIC will conduct a comprehensive factory acceptance test to ensure that the equipment meets technical standards and customer requirements.
The test items include insulation resistance test, short circuit impedance test, load test, and oil quality test to ensure the stability and safety of the transformer under various working conditions. No-load current test and no-load loss test are used to verify the energy efficiency and performance of the transformer. The temperature rise test ensures that the transformer will not overheat during operation, to ensure the long service life of the equipment. The partial discharge test is used to check whether there are potential insulation problems in the transformer. All test results are recorded in detail, and a test report and quality certificate are provided.
After passing the inspection, the transformer will be accompanied by a complete quality inspection certificate and finally packed and prepared. This process ensures that each transformer can meet international and industry standards and be reliably put into use.
Routine Test - Transformer Turns Ratio/TTR (All Tap Voltages)
Voltage source: usually AC 10 V to 30 V , used to test different voltages for each tap.
Temperature and humidity meter: used to record environmental conditions during the test to ensure test accuracy.
Current probe: used to measure the load current of the winding and ensure the accuracy of the test results.
Perform the test under suitable environmental conditions: relative humidity below 75% and no rain (recommended temperature: 20-30°C). Avoid high humidity or bad weather that may affect the test accuracy.
The voltage ratio between the windings
Deviation of the measured value from the rated ratio
0.5% < Turns ratio error ≤ 1% (caution)
Turns ratio error > 1% (further inspection or corrective action required)

Application
Technical Advantages
Product Packaging
Related Products
FAQ From Customers
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What is a Transformer?A transformer is an electrical device used to change the voltage of alternating current (AC). It works on the principle of electromagnetic induction, converting high-voltage current into low-voltage current or low-voltage current into high-voltage current. Transformers are widely used in power transmission, distribution systems, and various electronic devices.
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What are the main uses of a transformer?The main use of a transformer is voltage conversion. Transformers are used in power transmission systems to help transfer electricity from power plants to consumers. In addition, transformers are also used in electronic devices such as chargers, televisions, power adapters, etc., to adjust the voltage to meet the requirements of different devices.
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Do you have UL listed?Yes, our transformer has UL listed. We have exported to America many pad mounted transformer,substation transformer and HV.