6500kVA Double-Split Step-Up Substation Power Transformer 480V to 13.8kV IEC

Built for utility-scale solar, BESS and other 480 V generation systems, this 6500 kVA step-up transformer connects two inverter blocks—rated 3700 kVA and 2800 kVA—to a single 13.8 kV collector feeder. Each inverter block has its own 480Y/277 V winding and high-current terminal set, keeping the two low-voltage circuits separately connected inside one transformer.

For EPC contractors and plant owners, this double-split design eliminates the need for a separate step-up transformer for each inverter block and reduces the number of medium-voltage connection points. The unequal winding ratings match the actual capacity of the two inverter groups, while the outdoor conservator design and ONAN cooling support reliable operation without external cooling fans. The transformer is designed to IEC 60076 with a Dyn11,yn11 vector group.

• Single-Unit 6.5 MVA Step-Up Capacity: Consolidates dual low-voltage solar inputs into a single high-efficiency 13.8 kV grid connection, reducing substation footprint and equipment costs.
• 3700kVA + 2800kVA Double-Split Design: Flexibly pairs unequal inverter groups into one step-up transformer, eliminating the need to force identical block ratings across your solar array.
• High-Current Low-Voltage Interfaces: Built for massive current throughput, with LV inputs handling 4450.5 A and 3368.0 A continuous loads backed by heavy-duty 6000 A and 4500 A bushing assemblies.
• Conservator Oil Management System: Complete outdoor protection package—including oil conservator, moisture absorber, gas relay, and oil-level gauge—ensuring real-time condition monitoring and long-term oil preservation.

• Oil Conservator — Accommodates insulating-oil volume changes caused by thermal expansion and contraction.
• Moisture Absorber — Removes moisture from incoming air during transformer breathing cycles to help maintain insulating-oil quality.
• Gas Relay — Detects internal gas accumulation or sudden oil surges to provide early warning of internal faults.
• Oil Level Indicator — Provides a clear visual indication of the oil level inside the conservator to help prevent low-oil operation.
• Signal Thermometer — Monitors top-oil temperature in real time and provides alarm contacts for operating-condition monitoring.
• Pressure Relief Valve — Rapidly releases abnormal internal pressure to protect the transformer tank.
• Five-Position Off-Circuit Tap Changer — Provides ±5% voltage adjustment from 13.11 kV to 14.49 kV while the transformer is de-energized.
• Radiator Assemblies with Butterfly Valves — Provide efficient ONAN cooling and allow individual radiator isolation during field maintenance.
• 6000 A and 4500 A Low-Voltage Bushing Sets — Provide dedicated high-current interfaces for the 3700 kVA and 2800 kVA input windings.
• 15 kV Porcelain Bushings — Provide reliable, high-dielectric external connections for the 13.8 kV output circuit.
• IP54 Terminal Box — Protects control, alarm and sensor connections against dust and rain ingress.
• Drain Valve and Gate Valve — Facilitate oil sampling, draining and routine maintenance.
• Grounding Bolts — Provide designated protective-grounding connection points for safe site installation.
• Removable Protection Cover — Protects the low-voltage terminal area from accidental contact and weather exposure while retaining maintenance access.

1. With extensive experience in North American projects, Winley Electric designs substation transformers to meet applicable ANSI/IEEE, CSA, NEMA and related standard requirements.
2. With a stable supply chain, mature production processes, Winley Electric provides clear capacity-based lead times after technical approval: 8-10 weeks for transformers below 10 MVA, 10-12 weeks for 10-40 MVA transformers, and 18-20 weeks for 40-100 MVA transformers.
3. Winley Electric provides complete English technical documentation, 24/7 technical response, spare parts support, and a 2-year warranty to support project installation and long-term operation.

A: Winley provides clear capacity-based lead times after technical approval: 8-10 weeks for transformers below 10 MVA, 10-12 weeks for 10-40 MVA transformers, and 18-20 weeks for 40-100 MVA transformers. We also provide a detailed production schedule and real-time manufacturing photos to help track progress.We provide a detailed production schedule and real-time manufacturing photos to help track progress.

A: We offer a flexible MOQ of just 1 unit. Complete inquiries are quoted within 1-3 days with 24/7 support. Leveraging our extensive North American experience in renewable energy, data centers and large industrial projects, we ensure highly cost-effective and reliable solutions.

A: Yes, We accept OEM and ODM. Winley provides services for substation power transformers up to 100MVA, with HV systems up to 145kV. We can customize electrical parameters, structure, fluid, protection, switches, gauges, tank and paint according to customer drawings, with the capability to integrate components from brands like Qualitrol, Eaton Cooper, and MR.

A: Yes. Winley substation transformers are engineered and manufactured in strict accordance with ANSI/IEEE, CSA, NEMA, relevant ASTM standards and IEC 60076.We bring a proven track record across the United States and Canada, supporting critical applications in industrial manufacturing, renewable energy, and power distribution across a range of capacity and voltage requirements.

A: We deliver a complete compliance package: approval drawings, datasheets, nameplate drawings, routine test reports, installation manuals and accessory manuals. We also back your project with lifetime documentation support.

A: Winley ensures quality through strict ISO 9001 process management with dedicated QC oversight. Prior to delivery, every unit undergoes comprehensive routine testing, including Winding Resistance, Turns Ratio, Polarity and Phase Relation, and No-Load Loss and Excitation Current tests. We also fully support Factory Acceptance Testing (FAT) and third-party inspections (SGS).

A: Yes. Winley Electric provides tailored, fully controllable transportation solutions for large-scale transformer projects to ensure compliant customs clearance and zero-damage delivery. We actively assist in verifying critical logistics factors, including shipping dimensions, total weight, offloading conditions, site accessibility, and lifting/rigging requirements.

A: 24 months from B/L. During the warranty period, If there are any accessory problems, just provide photos of damaged accessory, then we will provide free service. According to the number of products, we will provide easily damaged accessories for free. We can also provide technical support if you need.