Potential Transformer Substation Manufacturers – Metering Grade Supply
Subian Electric manufactures potential transformers for substation metering and protection at its 50,000-square-metre factory in Xuzhou, Jiangsu, China. Subian’s 350+ employees have served utilities and panel builders in 50+ countries since 2019.
As a factory-direct manufacturer and supplier, Subian provides PTs with accurate ratios, stable accuracy and complete test documentation.
Send your voltage class and accuracy requirements. Subian’s export team will respond with a quotation and technical data.
Substation Potential Transformers Manufactured by Subian
Potential transformers for substation metering and protection, 10 kV to 35 kV class, cast resin or oil immersed, with routine testing on every unit.
What Is a Potential Transformer and Why Is Accuracy Important?
A potential transformer converts substation voltage to a standard low level for instruments. Accuracy matters because every protection decision and every meter reading starts from the PT signal.
A correctly rated PT with the right accuracy class keeps protection sensitive and billing fair. Subian confirms ratio, class and burden with your scheme before production.
What Buyers Check Before Ordering
- Metering & protection – accuracy classes from 0.2 to 3P.
- 10-35 kV class – voltage classes for substation duty.
- Stable accuracy – temperature-stable designs for long-term billing.
- 50,000m² factory – in-house winding, casting and testing.
- 350+ employees – engineering, quality and export teams.
- OEM / ODM & wholesale – custom branding, packaging and volume supply.
Main Types of Substation Potential Transformers
Subian manufactures two PT types:
Metering PT
Metering
High-accuracy units for energy measurement and billing.
Class 0.5 or 0.2S / IEC 61869-2
Protection PT
Protection
Units for voltage protection and synchronising schemes.
5P10 or 5P20 / IEC 61869-2
Substation PT Specifications
| Parameter | Specification |
|---|---|
| Rated voltage | 10 kV / 35 kV class |
| Secondary voltage | 100 V / 110 V / 120 V |
| Accuracy class | 0.2 / 0.5 / 3P |
| Insulation | Cast resin / oil immersed |
| Frequency | 50/60 Hz |
| Standard | IEC 61869 |
How to Compare Potential Transformer Substation Suppliers
Quotations for this equipment often look identical on the first page. The difference sits in what is attached behind the number, and in the three or four lines that decide the installed cost rather than the purchase price.
| What to compare | What a thin quotation leaves out | What to ask for |
|---|---|---|
| Enclosure construction | A steel box | Gauge, insulation, roof slope and the walk-in or non-walk-in choice |
| Ventilation | Passive louvers | Air path, filter class and the internal temperature rise at full load |
| Earthing | A terminal provided | Earth bar size, earth switch and the touch-voltage calculation |
| Auxiliary supply | Not mentioned | AC and DC auxiliary circuits, battery autonomy and the alarm list |
| SCADA interface | Optional | Protocol, points list and whether IEC 61850 is required |
| Documentation | Wiring diagrams | SLD, wiring, setting sheets and the as-built set in the agreed language |
Buyers who compare on price alone usually discover the gap at commissioning. The six lines above are the ones that decide whether the unit or the panel can be energised without site work. OEM and ODM supply is available where the nameplate, manual and packing have to carry a different brand.
Potential Transformer Substation Standards Buyers Ask For
The purchase specification decides the insulation level, the enclosure test and the nameplate data. These are the standards buyers normally name in the enquiry.
| Standard | What it covers | When it is asked for |
|---|---|---|
| IEC 62271-202 | Prefabricated substations | Compact and skid-mounted packages |
| IEC 60076-1 | Power transformers | The transformer inside the package |
| IEC 62271-200 | MV switchgear | RMU and incoming panels |
| IEC 61439-2 | LV assemblies | The LV distribution board |
| IEEE C57.12.28 | Enclosure integrity and tamper resistance | Public-access sites in North America |
| IEC 60529 | Degrees of protection (IP code) | Outdoor and coastal sites |
Where two standards conflict, the purchase specification wins and the conflict is recorded on the drawing before production. Type test reports are issued against the model, so ask for the report that names the rating you are buying.
PT Manufacturing at Subian’s 50,000 m² Factory
From winding to casting, assembly and testing – every PT is built and tested at Subian’s Xuzhou facility with accuracy verification.
Production Workshop
Controlled winding, core processing and vacuum drying with quality checkpoints between every stage, so quality is built in from the start.
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Quality & Testing Center
Routine inspection on every unit before delivery, with type test reports supporting project approval and market certification.
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Materials & Components
Core materials, windings and components are checked against the approved bill of materials on every production run.
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OEM / ODM / Agency Supply
Custom branding, packaging and configurations for global partners – from nameplate to complete product design – supported by a dedicated export team.
Learn More →OEM/ODM & Wholesale PT Supply for Panel Builders
Panel builders and distributors can brand or resell PTs with custom nameplates and documentation.
OEM / ODM
Factory-DirectCustom branding, packaging and product variants built on Subian’s standard platforms – from a nameplate to full product design.
Custom nameplate · Custom packaging · Full test docs
Wholesale Supply
Volume PricingFactory pricing with flexible container quantities, mixed models per container and reliable global shipping for volume buyers and importers.
Container MOQ · Mixed models · Global shipping
Distributor Support
Channel PartnersDedicated account management, technical documentation and priority production for distributors and project clients.
Account manager · Sales material · Priority lead times
Accuracy Class Selection: Metering vs Protection PTs
Metering PTs need high accuracy at normal operating voltage (0.2-0.5 class); protection PTs need predictable behaviour under fault conditions (3P class).
Subian confirms the accuracy class with your scheme before production, so the PT matches its job.
Choosing a Potential Transformer Substation Manufacturer
Verify accuracy test evidence, insulation quality and reference deliveries to utilities or panel builders.
Subian Electric offers a 50,000m² factory, 350+ employees, ISO9001, CE and UL certification and export to 50+ countries.
Send your voltage class and accuracy requirements – Subian confirms the design before production.
Certifications & Quality Assurance
Subian’s potential transformers are produced under ISO9001, ISO14001 and ISO45001 management systems, with CE and UL certification and type test reports.
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
Potential Transformer Substation FAQ
Common questions about potential transformers for substations and factory sourcing.
What is a potential transformer used for in a substation?
What accuracy class should I choose?
What secondary voltages are available?
Can PTs be supplied as part of a substation package?
What testing is done?
What are your delivery terms?
What is included in a Potential Transformer Substation?
Is a walk-in enclosure available?
Contact Subian
Need the Right Specification?
Tell Subian your target market, product type, quantity and technical requirements. Subian’s team will help you identify a suitable configuration for your project.