5000kVA Oil Immersed Substation Transformer
The 5000kVA Oil Immersed Substation Transformer is engineered for high-capacity power substations that demand continuous stability, strong load adaptability, and long operational life. Featuring an advanced oil-immersed insulation system, the transformer effectively enhances dielectric strength and thermal conductivity, ensuring reliable performance under heavy and fluctuating load conditions. With superior short-circuit withstand capability and efficient cooling performance, the transformer provides dependable power conversion for substations serving industrial, commercial, and infrastructure applications.
- Primary Voltage Ratings 34.5-19.92/13.8-7.957, 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, CE
- Application Temporary Power Supply Systems, Utilities
- Power Rating 5000kVA
- Certificate UL, CESI, IEEE
- Cooling Method ONAN, ONAN/ONAF, KNAN, KNAN/KNAF
- Oil Mineral Oil or FR3
- Opeartion Step Down & Step Up
Technical Specifications
Customization Optional
Packing and Shipping
Manufacturer Test
Routine Testing
Application
Technical Specifications
5000kVA Oil Immersed Substation Transformer
Technical Specifications
Accessories
| Rated Power | 5000kVA | |
| 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 | 850 kg | |
| Total Weight | 5000 kg | |
| Outline Dimensions（L×W×H）in. | 2650 × 1650 × 2450（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
5000kVA Oil Immersed Substation Transformer
NPC ELECTRIC's 5000kVA Oil Immersed Substation Transformer supports extensive electrical customization to adapt to different grid standards and project requirements. Primary and secondary voltage levels can be configured based on regional transmission and distribution systems, ensuring seamless integration into existing substations. Tap changer options, including off-circuit and on-load types, are available to provide precise voltage adjustment and stable output under variable network conditions. Temperature rise limits and insulation systems can also be tailored to match operational demands.
Structural and functional customization further enhances the adaptability of the transformer. Tank construction can be optimized for indoor or outdoor substation layouts, with corrosion-resistant coatings available for challenging environments such as coastal or industrial zones. Optional monitoring devices, protection accessories, and terminal arrangements can be integrated to improve operational visibility and safety. These customization options allow the 5000kVA oil immersed substation transformer to meet both technical and environmental requirements while maintaining high efficiency and reliability.
Packing and Shipping
5000kVA Oil Immersed Substation Transformer
Before packing, each 5000kVA Oil Immersed Substation Transformer undergoes a comprehensive inspection to confirm structural integrity, oil quality, and accessory completeness. The transformer is thoroughly cleaned and dried, and all openings are sealed to prevent moisture or dust ingress during transportation. Detachable components and sensitive fittings are carefully secured or packed separately to reduce transit risk.
The transformer is mounted on a heavy-duty base designed to withstand long-distance transportation. Protective wrapping materials are applied to shield the tank surface, bushings, and radiators from vibration, impact, and environmental exposure. Packing solutions comply with international logistics standards, ensuring the 5000kVA oil immersed substation transformer remains stable and protected during sea freight, land transport, or combined shipping methods.
Shipping arrangements are planned according to customer delivery terms and project schedules. The manufacturer works with experienced logistics providers to manage loading, route planning, and delivery timelines efficiently. All necessary documentation, including packing lists, inspection records, and conformity certificates, is prepared to support smooth customs clearance and on-time arrival.
Upon delivery, unloading instructions and handling guidance are provided to prevent damage during installation preparation. Reliable packing and professional shipping management help preserve the electrical and mechanical performance of the 5000kVA oil immersed substation transformer, ensuring it reaches the site ready for commissioning.
The transformer is mounted on a heavy-duty base designed to withstand long-distance transportation. Protective wrapping materials are applied to shield the tank surface, bushings, and radiators from vibration, impact, and environmental exposure. Packing solutions comply with international logistics standards, ensuring the 5000kVA oil immersed substation transformer remains stable and protected during sea freight, land transport, or combined shipping methods.
Shipping arrangements are planned according to customer delivery terms and project schedules. The manufacturer works with experienced logistics providers to manage loading, route planning, and delivery timelines efficiently. All necessary documentation, including packing lists, inspection records, and conformity certificates, is prepared to support smooth customs clearance and on-time arrival.
Upon delivery, unloading instructions and handling guidance are provided to prevent damage during installation preparation. Reliable packing and professional shipping management help preserve the electrical and mechanical performance of the 5000kVA oil immersed substation transformer, ensuring it reaches the site ready for commissioning.
32
32 years of industry experience
Manufacturer Test
5000kVA Oil Immersed Substation Transformer
Progress Test
Throughout manufacturing, the 5000kVA Oil Immersed Substation Transformer is subjected to systematic progress tests that monitor quality at each production stage. Core stacking inspections verify magnetic path accuracy to control losses, while winding formation tests ensure mechanical stability and electrical consistency. Intermediate measurements, including insulation resistance and turns ratio verification, are conducted to confirm that the 5000kVA oil immersed substation transformer maintains design parameters before final assembly, reducing the risk of defects and rework. Drying processes, oil filling supervision, and partial electrical checks are carried out to ensure optimal dielectric performance. By embedding the product specifications into every inspection step, the factory ensures the 5000kVA oil immersed substation transformer consistently meets performance expectations and operational reliability requirements prior to final testing.
Design Tests
All transformers will be tested after finishing the production, test items as follows:
♦ Insulation Power Factor
♦ Ratio, Polarity, and Phase Relation
♦ Winding Resistance
♦ 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 5000kVA Oil Immersed Substation Transformer is conducted in accordance with international transformer standards. Test items include winding resistance measurement, voltage ratio and vector group verification, applied voltage withstand tests, and insulation power factor assessment. Each procedure directly evaluates the electrical safety and functional accuracy of the 5000kVA oil immersed substation transformer, ensuring compliance before shipment. No-load and load loss measurements, temperature rise evaluation, and oil dielectric strength tests are performed to validate operational readiness. Completion of the FAT process confirms that the 5000kVA oil immersed substation transformer can operate reliably within demanding substation environments and long-term service conditions.
Routine Test - Winding Resistance
Purpose of Testing
The purpose of winding resistance testing is to detect the continuity and connection quality of the internal conductors of the motor or transformer windings, and to promptly detect potential faults such as open circuits, poor contact or local heating.
Testing Equipment
Winding resistance tester (e.g. OMICRON, DV Power, Raytech, Megger, ISA, etc.)
Test voltage source (commonly used are 6V, 10V, 20V, 40V or 100V, depending on the equipment model or customer requirements)
Temperature and humidity meter (used to record the ambient temperature and humidity during the test)
Test voltage source (commonly used are 6V, 10V, 20V, 40V or 100V, depending on the equipment model or customer requirements)
Temperature and humidity meter (used to record the ambient temperature and humidity during the test)
Pre-Test Preparation
Check if the instrument has been calibrated to ensure the test accuracy.
Disconnect the electrical connection between the test cable and the equipment to ensure that there is no external current or voltage interference.
Select a suitable voltage range for testing and set the test voltage according to the equipment requirements.
Disconnect the electrical connection between the test cable and the equipment to ensure that there is no external current or voltage interference.
Select a suitable voltage range for testing and set the test voltage according to the equipment requirements.
Test Progress
Connect the Test Instrument:
Connect the test equipment to the winding terminals of the device under test, making sure the connections are secure and properly grounded to avoid measurement errors.
Apply Test Voltage:
Select the appropriate test current according to the equipment specifications (such as test current for low-voltage windings, single-phase or three-phase windings).
Connect the test equipment to the winding terminals of the device under test, making sure the connections are secure and properly grounded to avoid measurement errors.
Apply Test Voltage:
Select the appropriate test current according to the equipment specifications (such as test current for low-voltage windings, single-phase or three-phase windings).
Measure and Record
Start the test and record the following parameters:
Winding resistance (usually expressed in units of "Ω")
Test current (A)
Test voltage (V)
Temperature (record the winding temperature before and after the test)
Winding resistance (usually expressed in units of "Ω")
Test current (A)
Test voltage (V)
Temperature (record the winding temperature before and after the test)
Temperature Correction
The measured winding resistance values are converted to a reference temperature (usually 20°C) based on a temperature correction formula to allow accurate evaluation and comparison.
Repeat Testing (if necessary)
Test the different windings (high voltage, medium voltage, low voltage) separately and make sure to record the resistance value of each winding.
Evaluation Criteria (Reference)
Resistance deviation is less than 5% (normal)
Resistance deviation is between 5% and 10% (warning)
Resistance deviation exceeds 10% (further inspection or corrective action is required)
Resistance deviation is between 5% and 10% (warning)
Resistance deviation exceeds 10% (further inspection or corrective action is required)
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
5000kVA Oil Immersed Substation Transformer is widely used in new energy grid connection projects, infrastructure projects, rail transit power supply systems and regional power distribution networks to meet the needs of continuous operation and high-reliability power supply.
Technical Advantages
● 30+ years of manufacturing experience
● ISO and UL certified production
● Customized cable and transformer solutions
Product Packaging
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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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