Dry Type Isolation Transformer
The Dry Type Isolation Transformer is a highly reliable power conditioning and electrical isolation solution designed to provide complete galvanic separation between input and output circuits. By eliminating direct electrical connections between the primary and secondary windings, the transformer effectively reduces electrical noise, suppresses transient disturbances, minimizes ground loop currents, and enhances system safety. Its oil-free design makes it particularly suitable for indoor installations where environmental protection, fire safety, and operational reliability are critical requirements. Manufactured using high-grade silicon steel cores, advanced vacuum pressure impregnated (VPI) insulation technology, and precision-wound copper or aluminum conductors, the Dry Type Isolation Transformer delivers superior voltage regulation, thermal stability, and dielectric performance. The transformer is widely utilized in industrial automation systems, medical facilities, commercial buildings, telecommunications infrastructure, data centers, renewable energy installations, and sensitive electronic equipment applications. Its maintenance-friendly design and robust construction ensure long service life and dependable performance under demanding operating conditions.
- Primary Voltage Ratings 220/220V, 380/380V, 480/480V, or custom
- Type Isolation Transformer
- Standards IEC 60076-11 / IEEE / ANSI
- Application data centers, server rooms, industrial automation systems
- Power Rating 5 kVA – 3000 kVA
- Certificate UL, CESI, IEEE
- Cooling Method AN (Natural Air) / AF (Forced Air)
Technical Specifications
Customization Optional
Packing and Shipping
Manufacturer Test
Routine Testing
Application
Technical Specifications
Dry Type Isolation Transformer
Dry Type Isolation Transformer Data Sheet
| Parameter | Specification |
| Product Type | Dry Type Isolation Transformer |
| Transformer Technology | VPI Dry Type / Cast Resin Dry Type |
| Rated Capacity | 1kVA – 5000kVA |
| Phase Configuration | Single Phase / Three Phase |
| Primary Voltage | 220V – 35kV |
| Secondary Voltage | Customized |
| Rated Frequency | 50Hz / 60Hz |
| Voltage Regulation | ≤ 2.5% |
| Efficiency | Up to 99% |
| Insulation Class | F Class / H Class |
| Dielectric Strength | IEC Standard Compliant |
| Winding Material | Copper / Aluminum |
| Core Material | CRGO Silicon Steel |
| Cooling Method | AN / AF |
| Temperature Rise | 80K / 100K / 125K |
| Noise Level | ≤ 50dB – 70dB |
| Electrostatic Shield | Optional |
| Harmonic Filtering Capability | Optional |
| Protection Degree | IP20 / IP23 / IP44 / IP54 |
| Thermal Monitoring | PT100 / Fiber Optic Sensors |
| Intelligent Monitoring | Optional |
| Communication Interface | Modbus / Ethernet |
| Operating Temperature | -25°C to +55°C |
| Relative Humidity | ≤ 95% |
| Installation Altitude | Up to 5000m |
| Fire Resistance Class | F1 Available |
| Environmental Class | E2 Available |
| Climatic Class | C2 Available |
| Service Life | More than 30 Years |
| Applicable Standards | IEC 60076-11 / IEEE / ANSI |
Customization Optional
Dry Type Isolation Transformer
The Dry Type Isolation Transformer provides extensive customization to meet stringent safety, performance, and installation requirements across various industries. Customers can select capacity, voltage ratio, and number of windings (single or three-phase). Multiple electrostatic shielding layers with independent grounding, ultra-low leakage current designs, and K-factor ratings (K-4 to K-20) are available for harmonic-rich environments. Enclosure options range from open-type IP20 to fully enclosed IP54 weatherproof cabinets with stainless steel construction for corrosive locations.
We also offer specialized medical-grade isolation transformers with enhanced creepage and clearance distances, integrated surge protection, temperature monitoring sensors with alarm relays, and smart communication interfaces (Modbus/RS485). Custom mounting arrangements, low-noise configurations with vibration dampers, and special finishes for architectural integration are available. These tailor-made solutions ensure maximum electrical isolation, noise suppression, and system compatibility for critical applications.
Packing and Shipping
Dry Type Isolation Transformer
The Dry Type Isolation Transformer is packaged with high-level protection to safeguard its resin-encapsulated windings and core during transportation. The unit is securely fixed on a reinforced wooden pallet with anti-vibration rubber pads and heavy-duty steel strapping. All terminals and enclosure parts are protected with custom foam inserts and rigid corner guards. The complete assembly is wrapped in multi-layer anti-static and moisture-proof film with sufficient desiccant packets. A sturdy, ISPM 15 fumigated wooden crate provides full enclosure with clear handling instructions and impact monitoring labels.
We offer secure and flexible shipping solutions tailored to customer needs. Sea freight in 20ft or 40ft containers with professional blocking and bracing is the most economical choice for international shipments, typically taking 20–50 days. Air freight is available for urgent or smaller capacity units. Domestic and regional transport uses specialized trucks with secure tie-down systems and weatherproof covering.
Full export documentation is prepared in advance, including commercial invoices, packing lists, certificates of origin, test reports, and safety compliance declarations to facilitate smooth customs clearance. Sustainable packing practices are prioritized by using recyclable materials and optimizing load configurations. Customers receive real-time GPS tracking and dedicated logistics coordinator support throughout the journey.
Upon arrival, we provide optional professional unpacking supervision, insulation resistance verification, and packaging disposal services. For bulk or project orders, consolidated shipments and phased delivery scheduling help reduce logistics costs and site management complexity. This careful packing and shipping process guarantees every dry type isolation transformer arrives in perfect condition, ready for immediate installation.
Each shipment includes a complete documentation package containing routine test reports, factory inspection certificates, operation manuals, maintenance guidelines, packing lists, wiring diagrams, quality assurance records, and export compliance documents. Additional certifications and project-specific documentation can be supplied upon request. The complete packing and shipping process is designed to ensure that every transformer arrives at its destination in excellent condition and ready for installation.
We offer secure and flexible shipping solutions tailored to customer needs. Sea freight in 20ft or 40ft containers with professional blocking and bracing is the most economical choice for international shipments, typically taking 20–50 days. Air freight is available for urgent or smaller capacity units. Domestic and regional transport uses specialized trucks with secure tie-down systems and weatherproof covering.
Full export documentation is prepared in advance, including commercial invoices, packing lists, certificates of origin, test reports, and safety compliance declarations to facilitate smooth customs clearance. Sustainable packing practices are prioritized by using recyclable materials and optimizing load configurations. Customers receive real-time GPS tracking and dedicated logistics coordinator support throughout the journey.
Upon arrival, we provide optional professional unpacking supervision, insulation resistance verification, and packaging disposal services. For bulk or project orders, consolidated shipments and phased delivery scheduling help reduce logistics costs and site management complexity. This careful packing and shipping process guarantees every dry type isolation transformer arrives in perfect condition, ready for immediate installation.
Each shipment includes a complete documentation package containing routine test reports, factory inspection certificates, operation manuals, maintenance guidelines, packing lists, wiring diagrams, quality assurance records, and export compliance documents. Additional certifications and project-specific documentation can be supplied upon request. The complete packing and shipping process is designed to ensure that every transformer arrives at its destination in excellent condition and ready for installation.
32
32 years of industry experience
Manufacturer Test
Dry Type Isolation Transformer
Progress Test
Early manufacturing progress testing for the Dry Type Isolation Transformer includes core material validation through Epstein frame testing to confirm low-loss performance. Copper winding resistance and inter-turn insulation tests are conducted before assembly. Electrostatic shielding layers are installed and tested for continuity and grounding effectiveness. Preliminary dielectric withstand and insulation resistance tests are performed between primary, secondary, and shield. These foundational checks, supported by digital traceability records, ensure the transformer meets high isolation and safety standards from the initial production stages. Mid-to-late stage progress testing features partial discharge measurement and power frequency withstand testing at elevated voltage levels. Leakage current testing under rated voltage confirms compliance with strict safety limits.
Design Tests
All transformers will be tested after production is finished. Test items are as follows:
♦ Insulation Power Factor
♦ Ratio, Polarity, and Phase Relation
♦ Winding Resistance
♦ Impulse Tests
♦ 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)
Factory Acceptance Test
Factory Acceptance Testing begins with accurate voltage ratio, polarity, and impedance measurements. No-load loss and excitation current tests confirm core efficiency. Full-load efficiency and temperature rise tests are performed to verify thermal performance. Dielectric withstand tests at elevated voltage levels and insulation resistance measurements validate galvanic isolation strength. Leakage current and shielding effectiveness tests ensure superior noise suppression. These routine electrical tests establish baseline performance and isolation integrity. Advanced FAT includes partial discharge testing under induced overvoltage to confirm low pC levels. Common-mode noise attenuation is measured across a wide frequency range.
Routine Test - Polarity 1-Ph
Purpose of Testing
The purpose of testing the polarity of a single-phase transformer is to ensure that the primary and secondary windings are correctly oriented, preventing issues like improper phase connection. It also verifies that the transformer operates safely and efficiently in the intended electrical system.
Testing Equipment
Test equipment: Polarity Tester (e.g. Megger, Hioki, etc.)
Voltage source: usually 500 V, 1000 V or customized as needed
Environmental monitoring: Temperature and humidity meter (records ambient temperature and humidity)
Voltage source: usually 500 V, 1000 V or customized as needed
Environmental monitoring: Temperature and humidity meter (records ambient temperature and humidity)
Pre-Test Preparation
Disconnect the device from the power supply and ensure that it is properly grounded and discharged.
Check the connection terminals and wiring to ensure that there is no looseness or contamination.
Test under suitable environmental conditions: relative humidity less than 75% and no rain (recommended temperature: 20-30°C).
Check the connection terminals and wiring to ensure that there is no looseness or contamination.
Test under suitable environmental conditions: relative humidity less than 75% and no rain (recommended temperature: 20-30°C).
Test Progress
Connect the Test Instrument:
Connect the test equipment to the bushing or terminal of the device under test and ensure proper grounding.
Apply Test Voltage:
Select the appropriate test voltage according to the rated voltage of the device. For single-phase systems, the applied voltage should comply with the equipment specifications (such as 220V or 380V, etc.).
Connect the test equipment to the bushing or terminal of the device under test and ensure proper grounding.
Apply Test Voltage:
Select the appropriate test voltage according to the rated voltage of the device. For single-phase systems, the applied voltage should comply with the equipment specifications (such as 220V or 380V, etc.).
Measure and Record
Start the test and record the following parameters:
Phase sequence: Confirm whether the phase sequence of the power supply is correct.
Polarity: Check whether the wiring meets the predetermined polarity (positive and negative terminals are connected correctly).
Voltage: The actual voltage value during the test.
Phase sequence: Confirm whether the phase sequence of the power supply is correct.
Polarity: Check whether the wiring meets the predetermined polarity (positive and negative terminals are connected correctly).
Voltage: The actual voltage value during the test.
Temperature Correction
Measure different wiring points (such as input and output) for comparative analysis to ensure that the electrical polarity is consistent.
Repeat Testing (if necessary)
If necessary, correct the measured parameters to the reference temperature (usually 20°C) to ensure the accuracy of the test results.
Evaluation Criteria (Reference)
Correct polarity: The wiring meets the expected polarity requirements and meets the standard. Reverse polarity: If reverse polarity occurs, it should be corrected immediately and retested. Polarity uncertainty: If there is any uncertainty, further check the power supply and wiring configuration.
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
Suitable for hospitals, data centers, industrial automation systems, laboratories, commercial buildings, telecommunications facilities, semiconductor manufacturing plants, and critical power distribution networks.
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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