630kVA Three-Phase Oil-Immersed Outdoor Substation Transformer | 220V to 380V Step-Up Transformer
This 630kVA three-phase oil-immersed transformer is designed for outdoor substations, providing reliable voltage conversion from 220V to 380V. With a robust oil-immersed cooling system, it ensures excellent heat dissipation, stable performance, and long service life. Ideal for industrial facilities, commercial power distribution, and utility applications, this step-up transformer delivers consistent efficiency even under heavy load conditions.
- Primary Voltage Ratings 34.5-19.92/13.8-7.957/13.2-7.62/12.47-7.2, 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 power transformer
- BIL 30/95kV
- Standards IEEE, ANSI, NEMA, IEC, CE
- Application Power Substations, Industrial Power Supply
- Power Rating 650kVA
- Certificate UL, CESI, IEEE
- Cooling Method ONAN, ONAN/ONAF, KNAN, KNAN/KNAF
- Oil Mineral Oil or FR3
- Opeartion Step Up
Technical Specifications
Customization Optional
Packing and Shipping
Manufacturer Test
Routine Testing
Application
Technical Specifications
630kVA Three-Phase Oil-Immersed Outdoor Substation Transformer | 220V to 380V Step-Up Transformer
Technical Specifications
Accessories
| Rated Power | 650 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 | 830 kg | |
| Total Weight | 2650 kg | |
| Outline Dimensions（L×W×H）in. | 1900 × 1000 × 1850（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
630kVA Three-Phase Oil-Immersed Outdoor Substation Transformer | 220V to 380V Step-Up Transformer
Our 630kVA three-phase oil-immersed outdoor substation transformer offers extensive customization to meet different project requirements. Voltage input and output levels can be tailored, including special configurations for regional grid standards or unique industrial systems. We also provide multiple capacity adjustments, cooling methods, and insulation grade options to ensure optimal performance under various environmental conditions. Customers can choose from different tap changer types—manual or on-load—to achieve precise voltage regulation based on operational needs.
Additionally, the transformer’s enclosure, protection level, and oil type can be customized for demanding outdoor environments, such as high humidity, coastal areas, or extreme temperatures. Enhanced features like anti-corrosion coatings, reinforced bushings, and smart monitoring devices can be added to improve durability and real-time performance tracking. For specific industry requirements, we offer tailored testing, certification, and branding options, ensuring every transformer is built to your exact standards for reliability, safety, and long-term efficiency.
Packing and Shipping
630kVA Three-Phase Oil-Immersed Outdoor Substation Transformer | 220V to 380V Step-Up Transformer
The packing and shipping process for the 630kVA Three-Phase Oil-Immersed Outdoor Substation Transformer 220V to 380V Step-Up Transformer is designed to ensure maximum protection and safe delivery to any global destination. Each transformer is secured inside a custom-built heavy-duty wooden crate engineered according to its dimensions and weight. The transformer is wrapped in moisture-resistant protective film to safeguard the oil-immersed body, windings, and bushings from dust, humidity, and environmental exposure. Shock-absorbing padding is added inside the crate to prevent vibration or movement during transport, ensuring that the 630kVA transformer remains stable, especially during long-distance transportation. Before packing, the oil levels, insulation components, and all external parts are inspected to confirm they meet factory standards.
For shipping, we offer flexible transportation methods, including land freight, sea freight, and air freight, depending on customer requirements and project timelines. All crates are reinforced with steel straps to withstand stacking pressure and rough handling. Detailed shipping labels, lifting instructions, and transformer specifications are clearly marked on the crate for easy identification and safe loading. For international shipments, our logistics team prepares complete export documentation, including packing lists, commercial invoices, test reports, and customs clearance paperwork to ensure smooth delivery.
Upon arrival, we coordinate with local logistics partners to arrange safe unloading using forklifts or cranes suitable for the weight of the 630kVA step-up transformer. Our team remains available throughout the transportation process to provide tracking updates, handle documentation, and assist with any delivery concerns. Through rigorous packing standards and professional shipping management, we guarantee that every 630kVA oil-immersed outdoor substation transformer reaches the installation site in perfect condition, ready for immediate operation.
32
32 years of industry experience
Manufacturer Test
630kVA Three-Phase Oil-Immersed Outdoor Substation Transformer | 220V to 380V Step-Up Transformer
Progress Test
The 630kVA three-phase oil-immersed outdoor substation transformer ensures that every unit meets strict performance and safety standards before delivery. The process begins with a detailed visual inspection to check the transformer’s exterior, bushings, wiring, and overall assembly. Electrical tests follow, including insulation resistance, winding resistance, polarity checks, and ratio tests to confirm accurate voltage transformation from 220V to 380V. A no-load test assesses core losses and noise levels, while a load test verifies efficiency and stability under full operating conditions.
Next, high-voltage and dielectric tests are conducted to evaluate insulation strength and ensure the transformer can withstand electrical surges. The transformer oil is also tested for dielectric strength, moisture content, and purity to guarantee optimal cooling and insulation performance. Finally, a temperature rise test simulates real working environments to confirm safe heat dissipation. All results are recorded to certify the transformer’s reliability and readiness for substation installation.
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
The Factory Acceptance Test for the 630kVA three-phase oil-immersed outdoor substation transformer verifies its quality and compliance before shipment. The FAT includes visual and dimensional checks, followed by key electrical tests such as insulation resistance, winding resistance, and voltage ratio accuracy. No-load and load tests assess performance, losses, and noise levels. High-voltage and dielectric tests ensure insulation reliability, while oil testing confirms dielectric strength and purity. A temperature rise test validates safe thermal performance. All results are documented to ensure the transformer meets required standards.
Routine Test - Dielectric Withstand (Hipot)
Purpose of Testing
The purpose of the Dielectric Withstand Test (or Hipot Test) is to check whether the insulation system of the equipment can withstand high voltage without breakdown or damage by applying a test voltage higher than the normal operating voltage of the equipment, thereby ensuring that the equipment will not have electrical failures in actual operation.
Testing Equipment
Hipot tester (e.g. Megger, Doble, OMICRON, HIOKI etc.)
Voltage source
Amperemeter
Grounding device
Temperature and humidity meter
Voltage source
Amperemeter
Grounding device
Temperature and humidity meter
Pre-Test Preparation
Disconnect the device from the power supply and ensure that the device is properly grounded and discharged.
Check all cables and connection terminals to ensure that they are secure and not loose.
Ensure that the test environment meets the requirements: relative humidity is less than 75% and there is no rain (recommended temperature: 20-30°C).
Check all cables and connection terminals to ensure that they are secure and not loose.
Ensure that the test environment meets the requirements: relative humidity is less than 75% and there is no rain (recommended temperature: 20-30°C).
Test Progress
Connect the Test Instrument:
Connect the Hipot tester to the bushing or terminal of the device under test correctly and ensure that the grounding is good.
Apply Test Voltage:
Select the appropriate applied voltage (such as AC or DC) according to the rated voltage of the equipment, and slowly increase the voltage to the specified value according to the specifications.
Connect the Hipot tester to the bushing or terminal of the device under test correctly and ensure that the grounding is good.
Apply Test Voltage:
Select the appropriate applied voltage (such as AC or DC) according to the rated voltage of the equipment, and slowly increase the voltage to the specified value according to the specifications.
Measure and Record
Record the leakage current (usually in μA or mA) during the application of the test voltage.
Record the applied voltage level and hold time.
Ambient temperature and humidity at the time of testing
Record the applied voltage level and hold time.
Ambient temperature and humidity at the time of testing
Temperature Correction
Correct the measured power factor to the reference temperature (typically 20°C) for accurate evaluation.
Repeat Testing (if necessary)
Test different windings, phases, relative to ground, relative to shielding layers, etc. Perform polarity reversal test (positive and negative high voltage switching) when necessary.
Evaluation Criteria (Reference)
Qualified standard: No breakdown or flashover at the specified test voltage. Unqualified standard: Breakdown, flashover or exceeding the maximum allowable leakage current value.
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
Power Substations, Industrial Power Supply, Renewable Energy Systems, Commercial Buildings, Electrical Equipment Maintenance and Upgrades
Technical Advantages
● 30+ years of manufacturing experience
● ISO and UL certified production
● Customized cable and transformer solutions
Product Packaging
Transformers Packaging (1)
Transformers Packaging (2)
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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.
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