10.5KV Oil Immersed Substation Transformer
The 10.5kV Oil Immersed Substation Transformer is specifically designed for medium-voltage power substations requiring stable voltage conversion and reliable long-term operation. Utilizing a proven oil-immersed insulation system, the transformer provides excellent dielectric strength and efficient heat dissipation, ensuring dependable performance under continuous load conditions. High-quality winding materials and precise manufacturing processes enhance mechanical strength and short-circuit resistance. With low operating noise and strong thermal stability, the transformer is well-suited for modern substations serving industrial, commercial, and infrastructure power distribution systems.
- 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 10.5kV
- Standards IEEE, ANSI, NEMA, IEC, CE
- Application renewable energy projects, infrastructure projects
- Power Rating 30kVA - 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
10.5KV Oil Immersed Substation Transformer
Technical Specifications
Accessories
| Rated Power | 30kVA - 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 | |
| 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
10.5KV Oil Immersed Substation Transformer
The 10.5kV Oil Immersed Substation Transformer supports comprehensive electrical customization to meet different grid standards and project specifications. Primary and secondary voltage configurations can be adjusted to align with local substation requirements, ensuring compatibility with regional power distribution systems. Off-load or on-load tap changer options are available to maintain voltage stability under fluctuating network conditions. Insulation levels, temperature rise limits, and cooling arrangements can also be customized to suit specific operating environments.
Structural and functional customization options further enhance installation flexibility. The transformer tank design can be optimized for indoor or outdoor substations, with optional corrosion-resistant coatings for industrial, coastal, or high-humidity areas. Accessories such as oil level indicators, temperature monitoring devices, pressure relief valves, and protection relays can be integrated as required. These customization solutions ensure the 10.5kV oil immersed substation transformer meets technical, environmental, and operational demands while maintaining high efficiency and reliability.
Packing and Shipping
10.5KV Oil Immersed Substation Transformer
Prior to packing, each 10.5kV Oil Immersed Substation Transformer undergoes a detailed inspection to verify assembly quality, oil condition, and accessory completeness. The transformer is cleaned, dried, and securely sealed to prevent moisture ingress during transportation. All connection points and external components are checked to ensure they are properly fixed and protected.
For packing, the transformer is mounted on a reinforced base designed to support its weight and prevent movement during transit. Shock-absorbing and moisture-resistant materials are applied to protect the tank surface, bushings, and radiators from vibration and environmental exposure. Packing methods comply with international transportation standards, making the 10.5kV oil immersed substation transformer suitable for long-distance shipping.
Shipping arrangements are organized according to customer requirements and project schedules. The manufacturer coordinates with experienced logistics providers to ensure safe handling, optimized routing, and timely delivery. Complete shipping documentation, including packing lists, inspection reports, and compliance certificates, is prepared to facilitate smooth customs clearance.
Upon arrival at the destination, unloading and handling instructions are provided to minimize installation risks. Reliable packing and professional shipping management help maintain the electrical and mechanical integrity of the 10.5kV oil immersed substation transformer from factory dispatch to site commissioning.
For packing, the transformer is mounted on a reinforced base designed to support its weight and prevent movement during transit. Shock-absorbing and moisture-resistant materials are applied to protect the tank surface, bushings, and radiators from vibration and environmental exposure. Packing methods comply with international transportation standards, making the 10.5kV oil immersed substation transformer suitable for long-distance shipping.
Shipping arrangements are organized according to customer requirements and project schedules. The manufacturer coordinates with experienced logistics providers to ensure safe handling, optimized routing, and timely delivery. Complete shipping documentation, including packing lists, inspection reports, and compliance certificates, is prepared to facilitate smooth customs clearance.
Upon arrival at the destination, unloading and handling instructions are provided to minimize installation risks. Reliable packing and professional shipping management help maintain the electrical and mechanical integrity of the 10.5kV oil immersed substation transformer from factory dispatch to site commissioning.
32
32 years of industry experience
Manufacturer Test
10.5KV Oil Immersed Substation Transformer
Progress Test
During production, the 10.5kV Oil Immersed Substation Transformer is subjected to structured progress tests that monitor quality at every manufacturing stage. Core stacking inspections ensure magnetic circuit accuracy to control losses, while winding process checks verify conductor placement and insulation consistency. Intermediate electrical tests, including insulation resistance and ratio measurements, are carried out to confirm that the 10.5kV oil immersed substation transformer meets design specifications before final assembly. Drying cycles, oil processing supervision, and sealing inspections are conducted to ensure stable dielectric properties. By integrating product-specific parameters into each inspection step, the factory ensures the 10.5kV oil immersed substation transformer maintains consistent quality and dependable performance prior to final acceptance 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
♦ 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)
♦ Insulation Resistance (Rated Voltage)
♦ Temperature Rise
♦ Dielectric Withstand (Hipot)
Transformer Factory Acceptance Test
The Factory Acceptance Test for the 10.5kV Oil Immersed Substation Transformer is performed in accordance with applicable international standards. Test items include winding resistance measurement, voltage ratio and vector group verification, applied voltage withstand tests, and insulation power factor evaluation. These procedures verify the electrical safety and functional accuracy of the 10.5kV oil immersed substation transformer before shipment. No-load and load loss measurements, temperature rise assessments, and oil dielectric strength tests are conducted to validate design performance. Completion of the FAT process confirms that the 10.5kV oil immersed substation transformer is ready for reliable service in medium-voltage substation environments.
Routine Test - Leak Test
Purpose of Testing
The purpose of water leakage test is to check whether there is leakage in the equipment or system, to ensure that it has good sealing and safety during use. The integrity of the equipment can be verified by simulating the pressure or load conditions in the working environment.
Testing Equipment
Leakage current tester (e.g. Fluke, Hioki, Megger, etc.)
Voltage source (usually 500V, 1 KV or 2.5 KV, customized according to test requirements)
Temperature and humidity meter
Ground electrode
Voltage source (usually 500V, 1 KV or 2.5 KV, customized according to test requirements)
Temperature and humidity meter
Ground electrode
Pre-Test Preparation
Ensure that the test environment conditions are suitable for leak testing. Test between 20°C and 30°C. Relative humidity should be less than 75% to avoid moisture affecting the test equipment and results.
Test Progress
Connect the Test Instrument:
Properly connect the test equipment (such as a leak detector) to the pipe, container or sealing structure of the device under test.
Apply Test Voltage:
Apply the appropriate test pressure (e.g. 10 bar, 15 bar, etc.) depending on the equipment's operating pressure or test standard.
Properly connect the test equipment (such as a leak detector) to the pipe, container or sealing structure of the device under test.
Apply Test Voltage:
Apply the appropriate test pressure (e.g. 10 bar, 15 bar, etc.) depending on the equipment's operating pressure or test standard.
Measure and Record
Start the test and record the following parameters:
Applied test pressure
Leakage (can be monitored by flow meter or other equipment)
Time record (to ensure that the test time meets the standard requirements)
Initial pressure and final pressure (if any changes)
Applied test pressure
Leakage (can be monitored by flow meter or other equipment)
Time record (to ensure that the test time meets the standard requirements)
Initial pressure and final pressure (if any changes)
Check for leaks
Check for leaks on equipment surfaces and joints by using a foam detector, gas leak detector, or other suitable method.
Repeat Testing (if necessary)
If the test finds leakage or there is any doubt, repeat the test as necessary to verify the sealing of different locations or different equipment parts.
Evaluation Criteria (Reference)
No leakage (excellent): No leakage during the test, the equipment is completely sealed.
Minor leakage (good): Very small leakage is allowed, and it is necessary to judge whether it is qualified according to industry standards.
Minor leakage (good): Very small leakage is allowed, and it is necessary to judge whether it is qualified according to industry standards.
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
10.5KV Oil Immersed Substation Transformer is widely used in renewable energy grid connection projects, infrastructure projects, rail transit power supply systems and regional power grid upgrades to meet the requirements of continuous operation and high reliability.
Technical Advantages
● 30+ years of manufacturing experience
● ISO and UL certified production
● Customized cable and transformer solutions
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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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