A 10kV dry type transformer is a medium-voltage distribution transformer commonly used to step a 10kV or 10.5kV supply down to 0.4kV for industrial and commercial loads. It uses solid insulation and air cooling instead of insulating oil, making it well suited to indoor locations where fire safety, clean operation and straightforward maintenance are priorities.
Selecting the correct unit requires more than choosing a kVA rating. The transformer must match the load profile, voltage system, impedance, vector group, installation environment and applicable project standards. This guide combines product fundamentals with the technical information an engineer or buyer should confirm before requesting a quotation.
The primary winding receives the medium-voltage supply and transfers electrical energy through electromagnetic induction to the secondary winding. The turns ratio determines the output voltage, while the core, winding conductor, insulation system and cooling arrangement determine losses, temperature rise, sound level and service capability.
A typical three-phase cast-resin unit includes a laminated electrical-steel core, resin-encapsulated high-voltage windings, low-voltage windings made from copper or aluminum, insulation supports, temperature sensors and connection terminals. An enclosure and cooling fans can be added when required by the installation.
Two dry type construction methods are commonly considered for medium-voltage projects:
The appropriate construction depends on site humidity, pollution, fire-performance requirements, maintenance conditions and the governing specification. The term “dry type” alone does not define environmental or fire classification.
The table below is a specification framework for quotation and technical review. Available values depend on the selected rating and project requirements; the approved datasheet and outline drawing control the final design.
| Parameter | Typical / Configurable Range | Information to Confirm |
|---|---|---|
| Product type | Three-phase cast-resin dry type transformer | Indoor or protected outdoor installation |
| Series | SCB series; efficiency generation selected by project | Required loss level or local efficiency regulation |
| Rated capacity | Common ratings from 30 to 2500kVA; other ratings subject to engineering review | Continuous load, starting load, harmonics and future allowance |
| Rated primary voltage | 10kV / 10.5kV / 11kV or project-specific | System nominal voltage and highest equipment voltage |
| Rated secondary voltage | Commonly 0.4kV; other outputs available by design | Required no-load secondary voltage |
| Frequency | 50Hz or 60Hz | Grid frequency |
| Phase | Three phase | System configuration |
| Tapping range | Commonly ±5% or ±2 × 2.5%, off-circuit | Utility voltage variation and tap positions |
| Vector group | Dyn11, Yyn0 or project-specific | Earthing, neutral and parallel-operation requirements |
| Short-circuit impedance | Selected by rating and system study | Fault level, voltage regulation and parallel operation |
| Winding conductor | Copper or aluminum | Loss target, size, weight and budget |
| Insulation system | Cast-resin winding; thermal class selected by design | Temperature-rise limit and ambient conditions |
| Cooling method | AN; AF available where engineered | Required base and fan-assisted rating |
| Enclosure | Open type or protective enclosure | Required IP degree, material and ventilation arrangement |
| Installation altitude | Standard design conditions or altitude-corrected design | Site altitude above sea level |
| Ambient conditions | Designed to the declared site conditions | Minimum/maximum temperature, humidity, dust and pollution |
Important: no-load loss, load loss, no-load current, sound level, partial discharge, dimensions and mass vary by capacity and design. These values should be listed in the project-specific technical offer rather than represented by one figure for every model.
These benefits depend on correct specification and installation. A dry-type transformer is not automatically maintenance-free, weatherproof or suitable for every harsh environment.
Common cast-resin model designations include SCB10, SCB11, SCB12, SCB13, SCB14 and later efficiency-oriented variants. A higher series number does not by itself define compliance in every market. Buyers should specify the required maximum losses, test standard and local efficiency rule instead of relying only on the model name.
| Capacity Group | Common Ratings | Typical Project Use |
|---|---|---|
| Small distribution | 30, 50, 80, 100, 125, 160, 200, 250kVA | Small workshops, auxiliary systems and local loads |
| Medium distribution | 315, 400, 500, 630, 800kVA | Commercial buildings, factories and packaged substations |
| Large distribution | 1000, 1250, 1600, 2000, 2500kVA | Large industrial loads, data centers and infrastructure |
For preliminary room planning, review the dry type transformer size and dimension chart. Final civil dimensions, foundation channels, ventilation clearance and transport access must be checked against the approved outline drawing.
The primary international product reference for this equipment is IEC 60076-11, which covers dry-type power transformers within its stated scope. Other parts of the IEC 60076 series may apply to general requirements, temperature rise, insulation levels, short-circuit withstand and sound measurement. GB/T requirements or another national standard may be used when specified in the contract.
The purchase specification should state the exact edition and any local grid or efficiency requirements. Do not assume that an IEC-designed product automatically carries a market-specific certification. CE, UL, RoHS or third-party certificates should only be shown when the certificate is available for the exact supplied configuration.
Temperature-rise, sound-level, environmental, climatic, fire-behaviour or short-circuit withstand evidence should be requested when the project specification requires type or special tests.
Core: laminated grain-oriented electrical steel designed to limit excitation current and no-load loss.
High-voltage winding: vacuum-cast resin construction for electrical insulation and mechanical support.
Low-voltage winding: copper or aluminum conductor selected for the required current and loss target.
Temperature monitoring: winding temperature sensors, controller and alarm/trip contacts.
Cooling: natural-air cooling with optional fans when an engineered AF rating is required.
Enclosure: optional protective housing with the IP degree, ventilation and material defined by site conditions.
Other options: anti-vibration pads, space heaters, surge protection, monitoring contacts and customized terminal arrangements.
Factories and processing plants: indoor distribution close to production loads.
Commercial buildings and hospitals: oil-free equipment for occupied or fire-sensitive areas.
Data centers: configurations engineered for redundancy, harmonics and critical-load requirements.
Metro, tunnel and airport projects: installations where fire behaviour and environmental class must be specified.
Solar and energy-storage projects: designs matched to converter duty, harmonics and bidirectional loading.
Packaged substations: coordinated with medium-voltage switchgear and low-voltage distribution equipment.
Marine or humid locations: only with a design and enclosure selected for the actual condensation, salt and pollution conditions.
Neither design is universally better. The correct choice depends on installation location, fire strategy, capacity, environmental conditions and lifecycle requirements.
| Factor | Dry Type Transformer | Oil-Immersed Transformer |
|---|---|---|
| Insulation and cooling medium | Solid insulation and air | Insulating liquid and external cooling surfaces |
| Typical location | Indoor or protected installations close to loads | Outdoor substations and higher-capacity duties |
| Leak containment | No transformer oil to contain | Oil containment and leak management may be required |
| Routine service | Cleaning, inspection, connection and ventilation checks | Includes oil condition and sealing-system checks |
| Environmental exposure | Requires a suitable enclosure and ventilation strategy | Sealed tank designs often suit outdoor exposure |
| Selection priority | Indoor safety, cleanliness and proximity to load | Capacity, outdoor service and heat dissipation |
The dry type transformer ratings and nameplate guide explains the fields that should match between the quotation, drawing and delivered equipment.
A useful price cannot be determined from “10kV transformer” alone. The main cost drivers are rated capacity, voltage ratio, copper or aluminum windings, guaranteed losses, impedance, enclosure, cooling accessories, temperature monitoring, required tests, documentation and delivery destination.
Compare quotations on guaranteed performance and scope, not model name alone. Check whether the quoted price includes the enclosure, fans, temperature controller, test reports, terminal arrangement, packing and delivery terms. A lower purchase price can be offset by higher electrical losses or missing project requirements.
10kV dry type transformer maintenance intervals should reflect load, environment, duty cycle and the manufacturer’s instructions rather than a fixed generic schedule.
For an accurate technical proposal, send the following information:
Need a project-specific datasheet and price? Contact Kampa Electric and attach your single-line diagram or transformer schedule. The engineering team can confirm the model, guaranteed parameters, outline dimensions and quotation for your application.
A common distribution ratio is 10/0.4kV, but 10.5/0.4kV, 11/0.4kV and other project-specific ratios are also used. The correct ratio must match the utility system and required low-voltage bus.
Standard project ratings commonly run from 30 to 2500kVA. Larger or non-standard ratings require engineering review. Select capacity from the load calculation rather than simply choosing the next model in a catalogue.
Both can be engineered to meet the specified performance. Copper can produce a more compact design, while aluminum may reduce material cost and weight. Compare guaranteed losses, temperature rise, dimensions and total project cost rather than conductor material alone.
Capacity, voltage ratio, conductor material, loss requirement, impedance, enclosure, accessories, testing, documentation and delivery terms all affect price. A meaningful quotation requires a technical specification or completed inquiry checklist.
The active part is normally intended for a controlled installation. Outdoor service requires a suitable enclosure and an engineering review of rain, dust, condensation, ventilation, temperature, corrosion and maintenance access.
AN uses natural air circulation. AF uses fans to increase airflow and may provide an engineered fan-assisted rating. The available overload or uprating must be confirmed for the specific design; it should not be assumed from the presence of fans alone.
