What’s the difference between isolation and autotransformers?

Isolation transformers have separate primary and secondary windings, providing full electrical separation between input and output circuits. They can step voltage up, step it down, or keep it the same (for example, 415 V → 415 V) while reducing electrical noise and improving safety for connected equipment. Autotransformers, by contrast, share a common winding and are typically used where isolation isn’t required. Offering a lighter, more compact, and cost-effective way to adjust voltage (such as 415 V → 220 V or vice versa).

Which kVA should I choose?

We size based on connected load, inrush, ambient temperature, and future capacity. Share your total load requirements for a recommendation. Unless specified, our transformers are designed for 100% duty cycle, meaning the transformer will operate 24/7 at the rated capacity, without the need of any cooldown periods.

Do you offer custom winding ratios and taps?

Yes. We can design your transformers to your specifications, to include custom primaries/secondaries, and can include common ±2×2.5% taps for fine voltage adjustment. Input voltage: up to 3.3kV Output voltage: up to 3.3kV kVA rating: up to 750kVA Configuration: Dyn11 (standard) but designed to your needs Optional additions: electrostatic screens, multiple inputs/outputs, ±% off-load tappings, switchgear

Can you supply copper or aluminium windings?

All SES transformers are wound with high-conductivity enamelled copper, never aluminium. Copper delivers superior electrical performance, lower losses, higher mechanical strength, and better long-term reliability, especially under high load or harmonic conditions. While aluminium designs may reduce upfront cost, copper windings ensure maximum efficiency, durability, and thermal stability, essential for critical industrial and commercial applications where downtime isn’t an option. SES Transformers are designed for 25+ years continuous operation, for when reliability, product life, and quality are priority.

Do you offer electrostatic screens?

Yes, we can fit electro-static screens between input & output windings of isolation transformers. These screens improve common‑mode noise attenuation for sensitive equipment.

What thermal class and temperature rise do you build to?

Typical builds are Class F or H with temperature rise tailored to the environment.

Are your transformers suitable for VFD or non-linear loads?

Yes. Our standard transformers are built to K4 rating , suitable for most VFDs, rectifiers, and other moderate non-linear load applications where harmonic currents are present. A K4-rated design allows for increased thermal capacity and reduced winding temperature rise under distorted load conditions. For more demanding systems, such as heavy harmonic or high K-factor environments, we can custom engineer transformers to any K-rating required, ensuring reliable performance, long service life, and compliance with your specific application.

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3 Phase Transformers

Professional voltage conversion and power protection for commercial and industrial equipment across Australia

Enquire About Power Transformer Solutions

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Australian-Made. Built to Last

All Southern transformers are locally designed and manufactured for long service life, with full compliance to Australian Standards.

Custom-Built for Industrial Demands

From commercial industries to major sectors, we tailor each transformer to meet the real-world needs of your application – no limitations.

Delivered to Your Schedule without Compromise

We understand project timelines matter – Southern delivers transformers to meet your schedule, fast or slow, without cutting corners.

5-year Warranty, 25+ year design life

Every transformer is designed and built to operate continuously at rated power for 25+ years, backed by an industry-leading standard 5-year warranty.

Our 3 Phase Transformer Range

Southern Electronic Services manufactures a comprehensive range of 3 phase transformers designed to solve your voltage compatibility and power protection challenges. Whether you’re operating imported equipment, protecting sensitive electronics, or need a custom voltage solution, our Australian-made transformers deliver reliable performance with fast turnaround times.

Standard ranges for most common input/output voltage needs
Custom solutions up to 3,300V @ 750kVA

3 Phase Isolation Transformers

For critical systems & equipment requiring isolation. Our range of dry-type isolation transformers are built to suit your needs, up to 3.3kV input/output & up to 750kVA size.

3 Phase Step Down Transformers

Ideal for running international 3-phase equipment in Australia. Stepping 415V down to your required voltage (200V, 220V, 380V, other)

3 Phase Custom Transformers

Our experienced team will design & construct your three-phase transformer to your specifications using only the best materials suited to your specific project needs.

We combine industry expertise with direct technical support, because we don’t take the trust you place in us lightly

Every transformer we build supports critical infrastructure — from mining operations, to data centres and industrial facilities.

We appreciate the pressure around compliance, lead times, and performance, and understand that transformer specifications are somewhat foreign to many.

That’s why we work closely with you from first enquiry through to delivery, ensuring the right design, the right specification, and long-term reliability.