33kV Substation Manufacturers & Suppliers – Factory-Built Compact Substations
Subian Electric manufactures compact substations and distribution equipment at our 50,000-square-metre factory in Xuzhou, Jiangsu, China. A 33kV substation built here arrives as one tested unit: the incoming 33kV switchgear, the step-down transformer and the low-voltage board are engineered together and assembled under one roof.
Because the factory controls the transformer, the MV switchgear integration and the final wiring, buyers get a single point of responsibility for quality. Our 350+ staff have supplied power grids, utilities and industrial customers in more than 50 countries since 2019.
Send your primary voltage, transformer rating and site conditions. Our engineers will respond with a single-line diagram, general arrangement drawing and quotation.
Since 2019 · 50,000m² · 350+ Staff
33kV Compact Substations We Build
Factory-built 33/11kV and 33/0.4kV prefabricated substations from about 50 kVA to 2,500 kVA, in terminal or ring-fed configurations, complete with protection, metering and LV distribution.
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10kV Dry-Type Transformer-SCBH series Amorphous Alloy
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20-35KV Dry-Type Transformer
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20-35KV SCB Series Epoxy Resin Dry-Type Transformer
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20KV Oil-immersed Distribution Transformer
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35KV Oil-immersed Power Transformer
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6-10KV Oil-Immersed Power Distribution Transformer
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Current Transformer –10KV Indoor High Voltage
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Current Transformer–LMZK Wound Current Transformer300/5a
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Current Transformer–LSY-10 transformer Integrated CT
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current transformer–LXK high voltage zero sequence
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dry type distribution transformer-6-10 KV SCB series epoxy resin cast
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Electrical Transformers–JDZ – 10 Power Voltage
What Is a 33kV Substation?
A 33kV substation receives power at 33kV and steps it down to a lower distribution level – most often 11kV or 400V/230V – so the energy can be fed into regional networks or local consumers. In the prefabricated compact form used widely by utilities and industrial sites, the incoming ring-main unit or breaker, the power transformer and the low-voltage switchboard share one weatherproof enclosure built at the factory.
Specifying a factory-assembled unit shortens on-site civil work, removes the need to coordinate several suppliers at a remote location, and delivers a plant whose protection grading, interlocking and cable routing were verified before shipment. That is why project teams increasingly choose this route over a site-erected building.
- 33 / 11 kV and 33 / 0.4 kV – standard configurations tailored to the network and the load.
- One tested enclosure – HV switchgear, transformer and LV panel coordinated and tested together.
- 50,000 m² factory – in-house enclosure fabrication, transformer build and switchgear wiring.
- Up to 110 kV experience – type-tested transformer designs support project approval.
- Full documentation – single-line diagram, drawings, test reports and manuals supplied.
- OEM / ODM & wholesale – utility branding, packaging and volume supply supported.
Common Configurations
We build three families of compact 33kV substation, matched to the incoming network and the load served:
33/11kV substation
Steps 33kV down to an 11kV distribution network. Typical for zone substations, regional feeders and plants that run their own 11kV system.
33/0.4kV substation
Feeds 400V/230V consumers directly from a dedicated 33kV intake, common for commercial and light-industrial sites.
Ring-fed & terminal types
Loop or radial connection via ring-main units, with metering, protection and optional telecontrol.
33kV Substation Technical Data
| Parameter | Specification |
|---|---|
| Rated HV voltage | 33 kV (max. system voltage 36 kV) |
| Rated LV voltage | 11 kV / 0.4 kV |
| Transformer rating | 50 – 2,500 kVA per project |
| HV switching | Ring-main unit / load-break switch / VCB |
| LV switchboard | Fixed or withdrawable, per project |
| Enclosure | Weatherproof steel, IP43 – IP54 |
| Design standard | IEC 62271-202 / GB/T 17467 |
| Testing | Routine tests on every unit; type tests per design |
33/11kV, 33/0.4kV and 132/33kV – Which Voltage Level Do You Need?
Network planners search by these level pairs because they describe where the substation sits in the system. A 132/33kV substation feeds a 33kV distribution backbone from the transmission or sub-transmission network; a 33/11kV unit supplies 11kV feeders for urban or industrial areas; and a 33/0.4kV unit delivers low voltage straight to consumers.
For a project connected at 33kV with downstream loads at 11kV, the single-line diagram typically shows the 33kV incoming bay with an isolator and breaker, a metering VT and CT set, the step-down transformer, and outgoing 11kV breaker panels. When the outgoing side is 0.4kV the same arrangement ends in a low-voltage main board with outgoing feeder breakers.
Tell us the two voltage levels on your diagram – the rest of the configuration follows from the load and protection requirements.
Buying a 33kV Substation: From Enquiry to Delivery
Buyers searching locally for a 33kV substation usually work through an electrical contractor, an EPC firm or a utility engineering department. Wherever the project is located, the factory supports those partners with drawings, type-test evidence and commissioning documentation.
The delivery cycle follows our standard cooperation flow: requirement review, technical confirmation, quotation, drawing approval, manufacturing and inspection, then packing and shipment coordination. Single-line diagram and general arrangement drawings are issued for approval before production starts, and a project manager keeps you updated on progress.
How a Compact 33kV Substation Is Manufactured
Enclosure fabrication, transformer production, switchgear wiring and final testing all happen on one site in Xuzhou, so the complete substation is built and checked as a single product.
Production Workshop
Transformer assembly and electrical integration move through controlled stations, with quality checkpoints between every stage.
Quality & Testing Center
Every unit is inspected before delivery and routine test records are issued with the shipment.
Materials & Components
Core steel, windings, switchgear and accessories are checked against the approved bill of materials.
Packing & Delivery
Substations are protected for sea freight, marked and loaded under a coordinated dispatch plan.
33kV Substation Factory Quote – Request Pricing
Tell us the incoming voltage, the transformer rating and the site conditions, and our engineers will prepare the single-line diagram, general arrangement drawing and a factory quotation with lead time for your project.
OEM / ODM & Wholesale Substation Supply
Utilities and distributors can take 33kV substations under their own brand, with custom nameplates, colour, packaging and documentation.
OEM / ODM
Custom branding, layouts and ratings built on our standard compact-substation platforms.
Factory direct · Test docs · Export support
Wholesale Supply
Volume Pricing
Factory pricing with mixed configurations per order for importers and channel partners.
Factory direct · Test docs · Export support
Distributor Support
Channel Partners
Drawings, tender documentation and priority production for distributors and EPC clients.
Factory direct · Test docs · Export support
Prefabricated vs Site-Built Substations
A prefabricated 33kV substation concentrates the engineering risk in the factory: components are matched, wired and tested before delivery, and installation on site is reduced to foundation work plus cable and earth connections. A site-built substation offers unlimited layout freedom but requires more civil works, longer programmes and coordination between several trades.
For sites where speed, relocatability or restricted space matters – distribution zones, industrial plants, mining and temporary supplies – the compact factory-built unit is usually the practical choice. For very large ratings a conventional yard remains appropriate, and our engineers will confirm which approach fits your project.
Choosing a 33kV Substation Supplier
Compare suppliers on evidence rather than price alone: ask for the type-test report against IEC 62271-202, the enclosure IP rating and corrosion protection, the brand and ratings of the switchgear installed, and reference deliveries to utilities in your region.
Because the transformer represents most of the substation value, check that the supplier actually manufactures it. Subian controls the transformer, the enclosure and the MV integration at one factory, with ISO9001, ISO14001, ISO45001, CE and UL certification, and a 110 kV transformer type-test report in our documentation set.
Request the single-line diagram and general arrangement drawing with your quotation – a manufacturer that engineers the unit for your network is a safer partner than one that only resells standard boxes.
Certifications & Quality Assurance
Our 33kV substation and transformer production is covered by ISO9001, ISO14001 and ISO45001 management systems, CE and UL certification, and type-tested transformer designs that support utility project approval.
Product Certifications
10 kV Dry-Type Transformer Certificate
35 kV Transformer CB Certificate
35 kV Transformer CE Verification
Transformer CE Certificate
Dry-Type Transformer Test Verification
ISO 14001 Environmental Management
ISO 45001 Health & Safety
ISO 9001 Quality Management
110 kV Transformer Type Test Report
UL Certificate of Compliance
33kV Substation Manufacturers & Suppliers FAQ
Common questions about 33kV substations, their voltage levels and factory sourcing.
What is a 33kV substation?
Is 33kV considered high-voltage?
How does a 33kV transformer work?
What is the purpose of a 33kV isolator in a substation?
What is the difference between 33/11kV and 33/0.4kV substations?
How long does a compact 33kV substation take to install?
Contact Subian
Need the Right Specification?
Tell us your target market, product type, quantity and technical requirements. Our team will help you identify a suitable configuration for your project.