SCB10 / SCB11 / SCB12 Series Three-Phase Cast Resin Dry-Type Distribution Transformer
The GOHO SCB10 / SCB11 / SCB12 series is a complete family of three-phase cast resin dry-type distribution transformers, offering three insulation and loss classes in one platform. All models share the same epoxy-resin vacuum-cast winding technology, naturally air-cooled (AN) construction, and a capacity range of 30–2500 kVA, with standard primary voltage 10 kV and secondary voltage 0.4 kV for indoor power distribution.
The transformer features class-F or class-H insulation with vacuum-cast epoxy resin, making it naturally flame-retardant, self-extinguishing and maintenance-free. The dry-type design eliminates the risk of oil leakage and fire, allowing safe installation in commercial buildings, industrial plants, basements and areas with strict environmental or fire-safety requirements.
Built on the same core platform, the three models differ mainly in no-load and load losses. SCB10 is the economical entry model for budget-sensitive projects; SCB11 meets mainstream indoor substation and energy-efficiency requirements; SCB12 delivers the lowest losses in the series for long operating hours and green-building tenders.
Model Comparison
| Attribute | SCB10 | SCB11 | SCB12 |
|---|---|---|---|
| Efficiency Class | Standard / Legacy | Mainstream energy-saving | High-efficiency / Green-building |
| No-Load Loss | Baseline | Lower than SCB10 | Lowest in series |
| Load Loss | Baseline | Lower than SCB10 | Lower |
| Insulation Class | Class F / Class H | Class F / Class H | Class F / Class H |
| Cooling | AN (Air Natural) | AN (Air Natural) | AN (Air Natural) |
| Best For | Budget-sensitive projects | Mainstream indoor substations | High-duty-cycle / energy-saving sites |
* Exact loss values (W) for each capacity follow GB/T 1094.12 / GB 20052-2020; contact us for the type-test report of your required capacity.
Technical Specifications
| Item | Specification |
|---|---|
| Rated Capacity | 30 – 2500 kVA |
| Rated Voltage (HV) | 10 kV / 11 kV / 10.5 kV (tap range ±5% in two steps) |
| Rated Voltage (LV) | 400V / 415V / 690V |
| Rated Frequency | 50Hz / 60Hz |
| Number of Phases | Three-phase |
| Connection Group | Dyn11 / Yyn0 (selectable) |
| Voltage Regulation | ±5% (off-circuit tap changer, 2 steps) |
| Cooling Method | AN (Air Natural) — optional AF (forced air) |
| Insulation Class | F / H |
| Winding Construction | Epoxy resin vacuum cast, self-extinguishing, moisture-resistant |
| Temperature Rise Limit | 100 K (F-class) / 125 K (H-class) |
| Degree of Protection | IP00 (core & coil) / IP20 / IP23 / IP31 (enclosure options up to IP54) |
| Ambient Temperature | -25°C to +40°C |
| Relative Humidity | ≤ 95% (non-condensing) |
| Altitude | Up to 1000 m (derating required for higher altitudes) |
| Standards | GB/T 10228, GB 1094, IEC 60076 |
Key Features
Cast Resin Fire-Safe DesignContains no insulating oil, eliminating the risk of oil leakage, pool fires or soil contamination. The flame-retardant, self-extinguishing epoxy insulation allows installation inside buildings, basements and tunnels without oil containment or fire-separation walls.
Vacuum-Cast Epoxy Winding InsulationThe windings are vacuum-cast in void-free epoxy resin, delivering high dielectric strength, excellent moisture and condensation resistance, and stable thermal performance across the full operating temperature range.
Natural Air Cooling (AN)Optimized core and winding geometry enable natural air convection cooling with no oil pumps, fans or radiators required for normal operation — reducing auxiliary power consumption, noise and maintenance.
Low-Loss Silicon Steel CoreHigh-grade grain-oriented silicon steel core material and improved joint design minimize no-load losses. SCB12 offers the lowest losses in the series, delivering measurable energy savings over the transformer’s 20+ year service life.
Non-Excitation Voltage RegulationAn off-circuit (de-energized) tap changer provides ±5% voltage regulation in two steps, enabling field adjustment of the voltage ratio to match local distribution network conditions.
Three Loss Classes, One PlatformSCB10, SCB11 and SCB12 share the same core, winding process, mounting dimensions and enclosure options, letting customers select the efficiency level that fits their budget and energy standard without redesigning the installation.
Reduced Installation FootprintThe dry-type construction requires no oil pit, conservator, breather or fire-suppression systems. Transformers can be installed close to load centers indoors, saving civil works and substation space.
Applications
- Commercial and residential building indoor substations
- Industrial plants, data centers and manufacturing facilities
- Underground substations, tunnels and metro power distribution
- Hospitals, schools, airports and public buildings with fire-safety requirements
- Renewable energy projects (solar, wind) step-up / step-down auxiliary power
- Infrastructure and utility distribution networks
- Marine, offshore and corrosive environments with proper enclosure
Which Model Should You Choose?
| Choose This Model | When… |
|---|---|
| SCB10 | Budget-sensitive projects, temporary installations, non-critical loads |
| SCB11 | Mainstream indoor substations, commercial and industrial distribution |
| SCB12 | Long operating hours, energy-saving tenders, green-building projects |