Products · Transformers

ONAN Power Transformer with On-Load Tap Changer

Three-phase oil-immersed power transformer with conservator and on-load tap changer (OLTC) for substation-grade voltage regulation.

ONAN oil-immersed three-phase power transformer with conservator and on-load tap changer

Overview

A three-phase, ONAN-cooled oil-immersed power transformer fitted with a conservator tank and on-load tap changer (OLTC), allowing voltage ratio adjustment under load without interrupting supply — typical for substation-grade voltage regulation on transmission and sub-transmission networks.

Sourced through our manufacturing network, including ultra-high-voltage capability through our selected manufacturing partners, and reviewed by our technical team against your capacity, voltage class and site requirement before quotation.

Technical Specifications

Cooling method: ONAN (with ONAF/OFAF options subject to manufacturer)

Tap changer: on-load (OLTC), motor-driven

Tank type: conservator with oil conservator tank

Rated capacity, voltage class and vector group: confirmed per project

Insulation level and impedance: confirmed per project

Protection accessories: Buchholz relay, pressure relief device, temperature indicators (configuration confirmed per project)

Capacity, voltage class, vector group and impedance are confirmed against your project's specification before quotation — available upon project requirement.

Applicable Standards

Can be supplied and tested in accordance with applicable IEC, IEEE/ANSI, CSA, GOST and destination-market requirements, subject to manufacturing partner and confirmed at quotation stage.

Customization Options

Capacity, voltage class, tap range, cooling method and protection/monitoring accessory configuration can be adapted through our manufacturing partner, including ultra-high-voltage requirements — confirmed per project.

Applications

Transmission Substations

Voltage regulation at grid transmission and sub-transmission points.

Industrial Power Supply

Large industrial sites requiring stable voltage under variable load.

Renewable Interconnection

Step-up regulation for solar and wind interconnection points.

Utility Substation Upgrades

Replacement and capacity-upgrade transformers for aging assets.

Drawings / System Diagrams

Drawings & System Diagrams

Outline drawings and single-line diagrams available upon request during technical review

Testing & Inspection

Routine tests, type tests, factory acceptance testing (FAT) and third-party inspection can be coordinated with the manufacturing partner, available upon project requirement. See Quality Control.

Available Documentation

Test reports, certificates and outline/GA drawings are compiled per order and depend on the manufacturing partner — confirmed at quotation stage.

FAQ

Frequently Asked Questions

What's the maximum voltage class available?

Through our selected manufacturing partners, ultra-high-voltage capability is available. Tell us your project's voltage class and we'll confirm feasibility.

On-load vs. off-load tap changer — which do I need?

On-load tap changers allow voltage adjustment without interrupting supply, typically specified for substation-grade regulation. We'll confirm the right choice during the technical review.

Request a Quote for This Product

Tell us your capacity, voltage class and site requirement and our engineering team will follow up.

Request a Technical Proposal