55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper
The 55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper is designed for reliable medium/high-voltage distribution networks. It adopts 99.95 % electrolytic copper windings, Class A insulation, a corrugated-fin tank, and ONAN cooling for excellent heat dissipation. Available in energy-saving S11/S13 series with no-load loss reduced by up to 35 %. Fully sealed or conservator type prevents oil aging. Equipped with ±5 % or ±2×2.5 % off-circuit tap changer (on-load optional). Meets IEC 60076, GB/T 1094 standards, lightning impulse withstand 250 kV peak, PD <10 pC. Low noise (<58 dB), strong short-circuit strength, suitable for harsh environments. Vacuum oil filling + nitrogen sealing ensures a 30+ year lifespan. Widely trusted in mining, petrochemical, renewable energy, and urban 55 kV substations.
- Primary Voltage Ratings 69kV 66kV 60kV or others
- Secondary Voltage Ratings 33/13.8/11 kV or customized
- H.V. Tap Range ±8×1.25% or others
- Type Oil-immersed power transformer
- BIL Up to 350kV
- Standards IEEE, ANSI, IEC, CSA
- Application step-up stations, port & railway electrification, heavy industrial parks
- Power Rating 250-1600kVA
- Certificate UL ,CESI ,ISO
- Cooling Method ONAN/ ONAF
- Opeartion Step Down & Step Up
Technical Specifications
Customization Optional
Packing and Shipping
Manufacturer Test
Routine Testing
Application
Technical Specifications
55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper
Technical Specifications
Accessories
| Rated Power | 250-1600kVA |
| Rating Primary Voltage | 69kV 66kV 60kV or others |
| Secondary Voltage |
33kV 13.8kV 11kV Customized |
| Frequency | 50/60Hz |
| Vector Group | Dyn11, YNd1, Dyn1, YNd11 or others |
| Winding Material | Aluminum/Copper |
| Efficiency | As IEEE, CAS Std or Customized |
| Impedance Voltage | As IEC |
| Altitude | ≤1,000m or Customized |
| Enclosure material | Mid Steel |
| HV Bushing |
| LV Bushing |
| OLTC/NLTC |
| Lifting hook for complete transformer |
| Name plate |
| Oil temperature |
| Winding temperature |
| Radiators |
| Oil level |
| Pressure relief valve |
| CT |
Customization Optional
55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper
The 55kV 1600kVA transformer offers extensive customization to perfectly match project specifications. Clients can select capacity from 1000 kVA to 2500 kVA, 100 % electrolytic copper or cost-effective copper-aluminum hybrid windings, and ultra-low-loss S11, S13, or S20 series cores. Primary voltage supports 52 kV, 55 kV, or 60 kV class with ±5 %, ±2×2.5 %, or non-standard tap ranges. Secondary voltage includes 11 kV, 13.8 kV, 10.5 kV, 6.3 kV, 0.69 kV, or 0.4 kV. Off-circuit tap changer is standard, while on-load tap changer (±8×1.25 % or ±10×1 %) with vacuum-type or resistor-type diverter and RTU interface is optional. The vector group can be Dyn11, YNd11, Yyn0, Dyn5, or any special connection. Cooling options include pure ONAN, ONAF with automatic fan control, or dual-stage forced-air systems. Tank design choices comprise fully sealed corrugated fins, a conservator type with silica-gel breather, or detachable radiator banks for easy maintenance. Impedance range 6–10 % adjustable upon request.
Additional advanced features include built-in current transformers (CT) and voltage transformers (PT) in separate compartments, fiber-optic winding hot-spot temperature monitoring (8–12 points), online dissolved gas analysis (DGA) and moisture monitoring, sudden pressure relay with trip/alarm contacts, oil regeneration/filtration interface, IP54/IP55 protective enclosure with sound-proof canopy, high-altitude compensation (>4000 m), seismic qualification up to 0.5 g, arctic low-temperature version (-50 °C), tropical anti-condensation heaters, marine C5-M/C5-X anti-corrosion painting, and full SCADA/Modbus/IEC61850 integration. Explosion-proof (Ex) design and arc-resistant internal fault protection are also available. Every customization is executed under strict IEC 60076, GB/T 1094 compliance, supported by complete type test and special test reports from international laboratories (KEMA, CESI, STL) when required, ensuring seamless integration into any 55 kV industrial, renewable energy, or utility project worldwide.
Packing and Shipping
55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper
Immediately after successful FAT and client sign-off, the transformer undergoes final vacuum oil treatment (<1 mbar, 72 h) followed by hot-oil circulation until moisture ≤8 ppm and dielectric strength ≥70 kV/2.5 mm. The tank is then filled with 99.999 % purity dry nitrogen to 0.025–0.035 MPa positive pressure and hermetically sealed. A calibrated digital pressure logger with 90-day memory is mounted on the conservator pipe to continuously record internal pressure during the entire journey. Double-sealed blind flanges, silica-gel breathers, and tamper-evident seals are applied to all openings. Nitrogen purity certificate and pressure trend report are included in the shipping documentation to prove perfect insulation integrity upon arrival.
All 55 kV porcelain bushings (HV & LV), neutral bushing, conservator tank (if applicable), radiator panels, OLTC operating handle, cooling fans, Buchholz relay, oil level indicator, winding/oil temperature gauges, sudden pressure relay, and marshalling box are carefully dismantled by certified technicians. Each item is wrapped in VCI anti-corrosion film, placed into custom IPPC-fumigated marine-plywood crates with ≥50 mm high-density anti-shock foam on all sides, and packed with 200 kg silica-gel desiccant per crate. Four 3-axis digital shock recorders (±200 g) and two electronic tilt indicators (±30°) are fixed to every crate. Crates are clearly labeled with part description, serial number, gross/net weight, and multilingual “Extremely Fragile – This Side Up” markings.
The main tank (gross weight approx. 19–23 tons) is welded onto a reinforced steel saddle skid with DNV-certified lifting lugs and 12 heavy-duty lashing points. The entire body is enclosed in a fully sealed wooden crate made of 25 mm marine plywood reinforced with 80×80 mm galvanized steel beams, then double-wrapped with 0.2 mm aluminum-foil moisture barrier and heavy-duty waterproof tarpaulin, heat-sealed at all joints. Eight high-precision digital impact recorders (trigger >3 g) and real-time GPS tilt monitors are permanently attached. External surfaces are painted bright yellow with permanent stenciling in English/Chinese/Spanish: “55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper – Do Not Roll – Keep Dry – Use Spreader Beam Only – Center of Gravity Marked”. IMO Class 9 labels and handling pictograms are applied.
Inland transport is performed by standard low-bed or hydraulic axle trailers (total height ≤4.5 m). Sea freight uses 40 ft open-top/flat-rack containers or break-bulk under-deck stowage with CCS/DNV-approved lashing using Φ22–Φ28 mm steel wire ropes and 50-ton turnbuckles. Full documentation package includes detailed packing list, IPPC fumigation certificate, certificate of origin (Form A/E), nitrogen pressure & trend report, shock recorder baseline data, 110 % all-risk marine insurance, third-party loading survey report, and complete installation manual. These comprehensive measures ensure every 55kV 1600kVA transformer arrives worldwide in perfect, ready-to-energize condition with zero damage.
All 55 kV porcelain bushings (HV & LV), neutral bushing, conservator tank (if applicable), radiator panels, OLTC operating handle, cooling fans, Buchholz relay, oil level indicator, winding/oil temperature gauges, sudden pressure relay, and marshalling box are carefully dismantled by certified technicians. Each item is wrapped in VCI anti-corrosion film, placed into custom IPPC-fumigated marine-plywood crates with ≥50 mm high-density anti-shock foam on all sides, and packed with 200 kg silica-gel desiccant per crate. Four 3-axis digital shock recorders (±200 g) and two electronic tilt indicators (±30°) are fixed to every crate. Crates are clearly labeled with part description, serial number, gross/net weight, and multilingual “Extremely Fragile – This Side Up” markings.
The main tank (gross weight approx. 19–23 tons) is welded onto a reinforced steel saddle skid with DNV-certified lifting lugs and 12 heavy-duty lashing points. The entire body is enclosed in a fully sealed wooden crate made of 25 mm marine plywood reinforced with 80×80 mm galvanized steel beams, then double-wrapped with 0.2 mm aluminum-foil moisture barrier and heavy-duty waterproof tarpaulin, heat-sealed at all joints. Eight high-precision digital impact recorders (trigger >3 g) and real-time GPS tilt monitors are permanently attached. External surfaces are painted bright yellow with permanent stenciling in English/Chinese/Spanish: “55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper – Do Not Roll – Keep Dry – Use Spreader Beam Only – Center of Gravity Marked”. IMO Class 9 labels and handling pictograms are applied.
Inland transport is performed by standard low-bed or hydraulic axle trailers (total height ≤4.5 m). Sea freight uses 40 ft open-top/flat-rack containers or break-bulk under-deck stowage with CCS/DNV-approved lashing using Φ22–Φ28 mm steel wire ropes and 50-ton turnbuckles. Full documentation package includes detailed packing list, IPPC fumigation certificate, certificate of origin (Form A/E), nitrogen pressure & trend report, shock recorder baseline data, 110 % all-risk marine insurance, third-party loading survey report, and complete installation manual. These comprehensive measures ensure every 55kV 1600kVA transformer arrives worldwide in perfect, ready-to-energize condition with zero damage.
32
32 years of industry experience
Manufacturer Test
55kV 1600kVA Three Phase Oil Immersed Power Transformer Copper
Progress test
The 55kV 1600kVA transformer is subjected to systematic, fully documented Progress Tests at every major production milestone, allowing real-time quality monitoring and immediate corrective action.
Stage 1 – Active Part Completion
- Individual coil insulation resistance and PI test (>2.5)
- HV & LV winding DC resistance at all tap positions
- Core insulation resistance, grounding current (<70 mA) and core loss preliminary measurement
Stage 2 – Pre-Tanking Verification
- Complete turns ratio test at all tap positions (tolerance ≤ ±0.5 %)
- Vector group and polarity confirmation
- Zero-sequence impedance measurement
- Low-voltage impulse test on each winding to detect turn-to-turn faults
Design Tests
All transformers will be tested after finishing the production test items as below:
♦ Leak testing with pressure for liquid-immersed transformers
♦ Test of transformer oil
♦ Measurement of voltage ratio and check of phase displacement
♦ Measurement of winding DC resistance
♦ Measurement of d. c. Insulation resistance between each winding to earth, and check of the core and frame insulation
♦ Capacitive bushing test
♦ Measurement of dissipation factor (tan δ) of the insulation system capacitances, and determination of capacitances windings-to-earth
♦ Measurement of no-load loss and current at 90%,100%,110% of rated voltage
♦ Operation test on on-load tap-changer
♦ Measurement of short-circuit impedance and load loss
♦ Lightning impulse test
♦ Induced-voltage test with partial discharge measurement
♦ Auxiliary wiring check
♦ Current transformer test
♦ Frequency response analysis test
Transformer Factory Acceptance Test
FAT is performed strictly per IEC 60076-1/3/5/11 with full client or third-party (SGS/BV/TÜV) witness and signed protocol.
Tests include:
- Load loss and short-circuit impedance at 75 °C/rated current
- Separate-source applied voltage withstand test
- Induced overvoltage withstand with PD measurement (<10 pC at 1.5Um/√3, <5 pC at Um/√3)
- Full-wave lightning impulse test 250 kV peak (55 kV side)
- Insulation resistance, PI (≥ 2.2), tanδ ≤ 0.004, oil BDV ≥ 70 kV
- Tap-changer full operation: 8–10 cycles at rated current + 50 auxiliary cycles
- Functional test of cooling system, Buchholz relay, sudden pressure relay, temperature indicators with 4–20 mA output
- Sound level measurement (<58 dB)
Complete raw data, calibration certificates, and oscillograms are provided. Only after client's signature is the transformer released for packing and shipment, guaranteeing 100 % readiness for immediate energization in 55 kV networks worldwide.
Routine Test - Transformer Turns Ratio/TTR (All Tap Voltages)
Purpose of Testing
The purpose of the transformer turns ratio (TTR) test is to confirm whether the voltage ratio between each tap of the transformer meets the design requirements and ensure that the transformer winding is connected correctly. By measuring the voltage ratio of each tap, it is possible to detect whether there is a fault or deviation in the transformer winding.
Testing Equipment
TTR tester: such as Doble, Megger, Omicron and other brands of transformer winding ratio tester.
Voltage source: usually AC 10 V to 30 V , used to test different voltages for each tap.
Temperature and humidity meter: used to record environmental conditions during the test to ensure test accuracy.
Current probe: used to measure the load current of the winding and ensure the accuracy of the test results.
Voltage source: usually AC 10 V to 30 V , used to test different voltages for each tap.
Temperature and humidity meter: used to record environmental conditions during the test to ensure test accuracy.
Current probe: used to measure the load current of the winding and ensure the accuracy of the test results.
Pre-Test Preparation
Disconnect all transformer tap-changers from the power supply and ensure that all equipment is properly grounded and discharged.
Perform the test under suitable environmental conditions: relative humidity below 75% and no rain (recommended temperature: 20-30°C). Avoid high humidity or bad weather that may affect the test accuracy.
Perform the test under suitable environmental conditions: relative humidity below 75% and no rain (recommended temperature: 20-30°C). Avoid high humidity or bad weather that may affect the test accuracy.
Test Progress
Perform the test under suitable environmental conditions: relative humidity below 75% and no rain (recommended temperature: 20-30°C). Avoid high humidity or bad weather that may affect the test accuracy.
Measure and Record
Start the test and record the following parameters:
The voltage ratio between the windings
Deviation of the measured value from the rated ratio
The voltage ratio between the windings
Deviation of the measured value from the rated ratio
Temperature Correction
If necessary, perform temperature correction on the measured turns ratio data (especially when testing at higher or lower temperatures). Generally, the standard reference temperature for temperature correction is 20°C.
Repeat Testing (if necessary)
Test the transformer's windings of different voltage levels (high voltage, medium voltage, and low voltage) separately to ensure that the turns ratios of all windings are normal.
Evaluation Criteria (Reference)
Turns ratio error ≤ 0.5% (pass)
0.5% < Turns ratio error ≤ 1% (caution)
Turns ratio error > 1% (further inspection or corrective action required)
0.5% < Turns ratio error ≤ 1% (caution)
Turns ratio error > 1% (further inspection or corrective action required)
*These comprehensive tests ensure that each transformer meets performance standards and operates
reliably under various conditions.
Application
Widely used in 55 kV regional substations, large mining operations, petrochemical plants, cement factories, wind/solar farm step-up stations, port & railway electrification, urban compact substations, and heavy industrial parks requiring a stable 11 kV or 6.3 kV supply with high reliability and minimum maintenance.
Technical Advantages
● 30+ years of manufacturing experience
● ISO and UL certified production
● Customized cable and transformer solutions
Product Packaging
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