Australian-Made. Built to Last

All Southern Transformers products 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 Transformers 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.

Get an Australian-Made Three-Phase Transformer

Reliable, Australian-Made Dyn11 Transformers – Built for 415V Systems

Our SD415 range offers a pre-engineered, cost-effective solution for 415V to 415V isolation, designed specifically for Australian commercial and industrial systems. Built in our Melbourne factory using high-quality copper windings and electrical-grade steel, these three-phase isolation transformers are ideal where galvanic isolation is required without a voltage step.

Like all our transformers, the SD415 range is manufactured to the highest standard – robust construction, thorough testing, and full compliance with AS61558 & AS60076. These are not imported catalogue products – they’re locally built to perform and to last.

For a full overview of our isolation range, visit our 3 phase isolation transformers page.

Get the right transformer in 3 quick steps

Our 3ph 415V Isolation transformer range has been designed to allow you to use 3ph 415V equipment from overseas right here in Australia, where our standard 3ph power is 415V (400V).

1. Choose your Power Rating and Enclosure type

Power Rating

Enclosure type

2. Check the specifications

Please complete the first step

3 Phase Isolation Transformers 415v/415v

Our 415 V / 415 V 3‑phase isolation transformers are dry‑type, custom‑built in Melbourne (up to 750 kVA), using enameled copper windings and electrical‑grade steel.

They provide full galvanic isolation with flexible vector group options (Delta-Star Dyn11, Delta-Delta, etc.), available in IP23 or IP65 enclosures—ideal for protecting equipment, reducing noise, and ensuring safe, reliable performance.

Key Features of the SD415 Range

Standard Dyn11 (Delta-Star) configuration – ideal for balancing phase voltages and shifting phase angle.
Other configurations are available as required.
Nominal Input/Output: 415V / 415V – no voltage change, just clean isolation
Power ratings from 10kVA to 750kVA – with customisation available beyond that.
Insulation Class H
Copper windings and terminals
Low voltage drop under load
Available in open frame or enclosed (IP23/IP65)
Optional ±2.5% and ±5% off-load tappings available
Optional Electrostatic screen

Transformer Solutions Made Simple

Provide your project details and we’ll respond promptly with expert guidance tailored to your needs.

(03) 9706 4202

Enclosures for Your Three-Phase Transformer

Southern Transformers can supply your transformer open, or encase your three-phase transformer in an oyster grey powder-coated steel enclosure for hard wiring. Our standard enclosures are rated at IP23 (indoor), or IP65 (outdoor) for when more protection is necessary. Outdoor enclosures typically come with wiring chambers fitted to the side to house input/output terminals.
Check this useful IP rating table.

We also offer wall-mounted enclosures for smaller 3-phase isolation transformers up to about 5kVA.

Why choose the SD415?

Designed specifically for 415V (400V) three-phase systems, which are standard across Australian industry.
Provides galvanic isolation to reduce electrical noise and improve safety.
Fast lead times.
Built in-house by our experienced team with over 45 years of transformer expertise.
Backed by a one-year warranty and a 25+ year design life

If you’re not sure of your transformer requirements, please give us a call at 03 9706 4202 and speak to our team.

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.