S20 High-Efficiency Oil-Immersed Distribution Transformer

The S20 series is a high-efficiency, fully sealed oil-immersed distribution transformer further upgraded from the S13 series.

It uses high-permeability cold-rolled silicon-steel sheets together with an optimized core-and-coil structure to reduce no-load losses and operating noise. The transformer is designed to provide stable electrical performance while improving energy efficiency during distribution operation.

The corrugated tank integrates cooling, breathing and volume expansion functions. Equipped with a pressure-release valve, the sealed structure helps isolate the transformer oil from external air and reduce oil degradation. Vacuum-annealed and epoxy-cured core treatment supports stable operation and a long service life. The S20 series is designed for power grid, renewable energy and industrial distribution projects.

01. High-Efficiency Core Design

High-permeability cold-rolled silicon-steel sheets and an optimized core-and-coil structure help reduce no-load loss and improve energy efficiency.

02. Ultra-Low No-Load Loss

The S20 series is designed to reduce no-load losses for efficient long-term operation in power distribution systems.

03. Fully Sealed Corrugated Tank

The corrugated tank integrates cooling, breathing and volume expansion functions while helping isolate transformer oil from external air and moisture.

04. Maintenance-Free Operation

The fully sealed structure helps reduce oil degradation and routine maintenance requirements under normal operating conditions.

05. Pressure-Relief Protection

A pressure-release valve is integrated into the sealed structure to support safe transformer operation. (sutelectrical.com)

06. Flexible Configuration

Capacity and voltage can be configured according to distribution network and project requirements.

07. Copper or Aluminum Windings

Copper or aluminum winding options are available according to product configuration and customer requirements.

08. NX2 Energy Efficiency Class

The S20 series is identified with the NX2 energy-efficiency class according to the current product information.

S
Three-phase transformer

M
Fully sealed structure

(B)
For capacities of 400 kVA and above, low-voltage foil-wound coils can be used

20
Performance level code

630
Rated capacity: 630 kVA

10
Voltage class: 10 kV

NX2
Energy efficiency class

Power Grid Distribution

Suitable for distribution network projects and power grid upgrading.

Renewable Energy

Applicable to new-energy power distribution projects.

Industrial Distribution

For factories and industrial electrical distribution systems.

Urban & Rural Power Distribution

Suitable for urban and rural distribution networks requiring efficient and reliable transformer operation.

What is an S20 transformer?

The S20 is a high-efficiency, fully sealed oil-immersed distribution transformer further upgraded from the S13 series.

What is the capacity range of the S20 series?

The current product information covers rated capacities from 30 kVA to 2,500 kVA. (sutelectrical.com)

What is the standard voltage configuration?

The listed S20 series uses 10 kV high voltage and 0.4 kV low voltage.

What is the vector group?

The listed series uses Dyn11.

What does NX2 mean?

NX2 is the energy-efficiency class identified in the current S20 model designation.

Is the S20 transformer fully sealed?

Yes. The S20 uses a fully sealed corrugated tank.

Does the S20 require regular maintenance?

The fully sealed structure is designed to support maintenance-free operation under normal service conditions.

Can copper and aluminum windings be supplied?

Yes. Copper or aluminum windings can be provided according to product requirements.

Can the S20 be customized?

Yes. Capacity, voltage and other configurations can be adjusted according to project requirements.

What applications are suitable for the S20?

The current product information identifies power grid, renewable energy and industrial distribution projects as application areas.