500kVA Dry Type 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 Dry type transformer
- BIL 30/95kV
- Standards IEEE, ANSI, NEMA,IEC
- Application Industrial equipment power distribution, commercial buildings, residential power distribution, power systems and distribution networks etc
- Power Rating 500kVA
- Certificate UL ,CESI
- Cooling Method OA/OF
- Opeartion Step Down & Step Up
Technical Specifications
Technical Specifications | ||
Rated Power | 500 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 | |
Enclosure material | 304 Stainless Steel | |
Total Weight | 1860 kg | |
Outline Dimensions(L×W×H)in. | 1560×1300×1850(mm) |
HV Bushing |
LV Bushing |
Tap changer connector |
Lifting hook for complete transformer |
Name plate |
Customization Optional
Packing and Shipping
The 500kVA Dry-Type Transformer is carefully packed and shipped to ensure it arrives in optimal condition. The transformer is first securely wrapped with weather-resistant plastic to protect it from dust, moisture, and environmental factors during transport. It is then placed on a sturdy wooden pallet or in a custom-built wooden crate, providing additional support and protection against impact or movement during transit.
For further protection, foam padding or shock-absorbing materials are used to cushion the transformer. The unit is labeled with clear handling instructions and shipping marks, indicating its weight, dimensions, and any special requirements for lifting or unloading.
The transformer is shipped using reliable and reputable carriers, and the packaging is designed to meet international shipping standards to prevent damage during both land and sea transport.
Upon arrival, the packaging is removed, and the transformer is carefully inspected for any transit-related damage before installation.


Manufacturer Test

Progress Test
NPC Electric manufactures high-quality three-phase dry-type transformers under strict quality control protocols. The 500kVA Dry-Type Transformer undergoes a comprehensive progress test to ensure it meets the highest quality and performance standards. This includes verifying key parameters such as voltage ratio, insulation resistance, and load testing under normal operating conditions. Additionally, the transformer is tested for temperature rise, ensuring efficient heat dissipation and safe operation. All tests are conducted in accordance with international standards, and the transformer is carefully inspected for compliance before delivery. These rigorous tests guarantee that the 500kVA Dry-Type Transformer operates reliably and efficiently in real-world applications.

Design Tests
All transformer will be test after finished the production, test items as below:
♦ Insulation Power Factor
♦ 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)
♦ Excitation & No-Load Loss (Rated Voltage)
♦ Applied Voltage
♦ Induced Voltage
♦ Lightning Impulse
♦ Insulation Resistance (Rated Voltage)
♦ Temperature Rise

Transformer Factory Acceptance Test
NPC Electric conducts rigorous quality control testing on every transformer or representative samples, as well as on specific components and materials, to ensure compliance with design specifications throughout the production process.
The Factory Acceptance Test (FAT) for a 500kVA three-phase dry-type transformer is a critical step performed before shipment to verify that the unit meets all applicable standards and delivers optimal performance. The FAT includes the following key procedures:
Visual Inspection: Evaluates the transformer’s physical condition, including the enclosure, terminals, and labeling, to ensure conformance with design and safety requirements.
Electrical Testing: Involves measuring winding resistance, insulation resistance, and performing turns ratio tests to validate electrical integrity and functionality.
Dielectric Strength Test: Applies high voltage across the insulation system to ensure it can endure both normal and transient operating voltages without failure.
Load Testing: Simulates real-world operating conditions to assess the transformer’s voltage regulation, temperature rise, and overall efficiency under load.
Protection Device Testing: Verifies the proper operation of integrated protective components such as thermal sensors, temperature relays, and tap changers (if applicable).
Routine Test - On load Loss Test
Voltage source and current source (usually rated voltage, or adjusted according to the test standard, such as 10 KV, 20 KV, 35 KV, etc.)
Temperature and humidity meter (used to record ambient temperature and humidity for correction of test data)
The test environment should be dry and rainless, with a relative humidity of less than 75% and a recommended temperature range of 20–30°C.
Connect the test equipment to the appropriate terminals of the device under test and ensure that all wiring is correct and the device is well grounded.
Apply Test Voltage:
Apply the specified test voltage at the rated frequency and adjust the low voltage side to maintain the rated current (or specified current).
On-Load Loss Power
Input Power and Output Power
Current
Voltage
Temperature (temperature rise or winding temperature)
Ambient temperature and humidity during the test

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.