12kV prefabricated transformer substation up to 3150 kVA for utility, EPC, industrial and renewable-energy projects—factory-assembled for coordinated MV, transformer and LV integration.
Request Technical ProposalSend Your SLDWhatsApp EngineerProduct Overview
YB-12 is a factory-assembled prefabricated substation integrating medium-voltage switching, transformer and low-voltage distribution compartments in one coordinated enclosure. The system is configured for utility distribution, industrial facilities, renewable-energy projects and infrastructure applications according to the project SLD, load, protection and installation requirements.

Customer Benefits
Compact Project Integration
Configuration focused on installation and system needs.
Engineering Coordination
SLD, GA and technical submittal support.
Flexible Configuration
Functional units selected for project scope.
Factory Testing
Inspection and FAT support before shipment.
Technical Parameters
| Item | Value |
|---|---|
| Series | YB-12 Series |
| Rated HV Voltage | 12 kV |
| Rated LV Voltage | 0.4 kV |
| Rated HV Current | 630 A |
| Frequency | 50/60 Hz |
| HV Short-Time Withstand Current | 20/25 kA, 4 s |
| Configuration | HV compartment + transformer compartment + LV distribution compartment |
| Transformer Capacity | Up to 3150 kVA subject to confirmed project design |
Standard selectable ratings are shown. Final transformer type, protection, enclosure, cooling and outgoing feeders follow the approved SLD and project technical agreement.
Functional Units and Configuration
HV Incoming & ProtectionTransformerLV Main IncomerOutgoing FeedersMetering & Compensation
Applications
Utility Distribution
Project-specific selection and engineering review.
EPC & Substation
Project-specific selection and engineering review.
Industrial Power
Project-specific selection and engineering review.
Solar & BESS
Project-specific selection and engineering review.
Infrastructure
Project-specific selection and engineering review.
Mining
Project-specific selection and engineering review.
Product Details
The enclosure is divided into independent MV, transformer and LV functional areas for clear operation and maintenance access. Door arrangement, ventilation, cable entry, enclosure material, colour and protection level can be coordinated with the approved project specification.
GA Drawing and Dimensions
GA drawings and overall dimensions are prepared after the project configuration is confirmed. Send the SLD, transformer capacity and enclosure requirements for an application-specific drawing.
Typical SLD
A typical SLD is provided after the MV, transformer and LV configuration is matched to the confirmed project scope.
Manufacturing and Quality
Assembly, busbar, secondary wiring, inspection, electrical testing and FAT evidence.
Downloads
YB-12 Product Catalogue
Public product-family catalogue for prefabricated substations up to 3150 kVA.
Project Documents
Final enclosure, transformer, MV/LV arrangement, drawings and SLD are project-specific.
FAQ
What information is required?
Voltage, current, fault level, frequency, quantity, SLD, BOQ and technical specification.
Can Qiangchi support OEM or EPC projects?
Project-specific configuration, drawings and document support can be discussed against confirmed requirements.
Have an MV Project?
Send us your voltage, quantity, SLD or technical specification.
Request Technical ProposalSend Your SLDWhatsApp EngineerModel Meaning
YB identifies a prefabricated compact-substation product family; 12 identifies the medium-voltage equipment class. Transformer capacity, MV unit, LV distribution, enclosure and auxiliary systems are selected for the project.
YB-12 compact substations can be evaluated up to 3150kVA. The final transformer rating, voltage ratio, vector group, impedance, tapping, MV/LV arrangement and enclosure depend on the approved specification.
Service Conditions & Project Confirmation
| Ambient temperature | Subject to project specification and technical confirmation |
|---|---|
| Altitude | State the installation altitude in the RFQ; derating or design review may be required |
| Relative humidity | Confirm maximum and average project conditions |
| Pollution and corrosion | State pollution level, salt mist, dust and corrosive atmosphere where applicable |
| Seismic condition | Project-specific requirement to be confirmed |
| Installation | Indoor or outdoor enclosure, cable entry, room dimensions and service aisle must be specified |
Standards and Technical Compliance
The applicable IEC standards, utility requirements, project specifications, inspection plan and document list are confirmed during technical clarification. Compliance statements apply only to the final approved configuration; no unverified certificate or test claim is implied.
Engineering, Packing & Shipment
After drawing approval, Qiangchi coordinates production, inspection, routine testing and the agreed FAT scope. Finished equipment is protected for handling and export shipment according to cabinet size, destination, transport method and contractual packing requirements.
Related Technical Guides
Review the Product Finder, Product Comparison and Selection Guides.
Request Project Configuration
Send the SLD, BOQ, specification, voltage, current, fault level, quantity and destination.
Verified model evidence
YB-12 Model-Specific Test Report
Report: XG20051080
Model: YB□ (STYB□)-12/0.4-1600
Verified scope: 12/0.4 kV; 1600 kVA
Test body: National High-low Voltage Electrical Apparatus Quality Inspection and Testing Center
Status: Archived model-specific report; original checked
This report applies only to the stated model and scope. Full report interiors remain controlled.
Reviewed by Qiangchi Engineering Team · Updated September 13, 2026
Engineering Answers for YB-12 Prefabricated Transformer Substation
What is this product?
YB-12 Prefabricated Transformer Substation is a Qiangchi medium-voltage product configured for project-specific distribution requirements.
Which voltage levels are available?
12 kV class, with transformer capacity up to 3150 kVA subject to project design.
Where is it used?
It is used in utility, industrial, commercial and renewable-energy distribution applications.
How to select the configuration?
Selection follows the system voltage, rated current, short-circuit level, functional units, protection concept, cable interface, installation conditions and approved SLD.
Which standards and tests apply?
Standards, routine tests and FAT scope follow the approved transformer, MV and LV configuration.
What information is required for quotation?
Send the SLD, system voltage, frequency, rated current, short-circuit level, quantity, project stage, required documents and delivery requirements.