PRODUCTS > THREE-PHASE TRANSFORMERS

Custom Three-Phase Transformers, Delta or Wye

Pacific Transformer designs and builds custom three-phase transformers in delta and wye configurations — isolation, step-up, step-down, and autotransformer designs from a few kVA up to 750 kVA, wound to your voltages, vector group, and footprint.

Free engineering designs. Quotes in 24 hours. Prototypes in 48. Catalog pricing on custom work.

Get a Custom Quote About Us

Custom three-phase transformers for industrial power distribution

Wound to Spec

Three-Phase Transformers, Wound to Spec

Three-phase transformers move real power. They are what sits between the service and the plant floor — converting 480 V to 240 or 208 V for distribution panels, deriving a neutral where the supply has none, or isolating a drive line-up from the rest of the building. The configuration matters as much as the rating: delta-wye, wye-delta, delta-delta, and wye-wye each behave differently with respect to grounding, harmonics, and phase shift.

We wind three-phase units in delta and wye, in isolation, step-up/step-down, and autotransformer construction, from a few kVA up to 750 kVA, at 50, 60, or 400 Hz. Tell us the primary, the secondary, the connection you need, and where it has to fit — our engineers spec the rest for free, and every unit is individually tested before it ships.

Send us your specs

Typical Specifications PTC-3P

Configuration Three-phase — delta & wye

Voltage Ratios 480 / 240 / 208 V + custom

Design Types Isolation, step-up/down, autotransformer

Power Range A few kVA up to 750 kVA

Frequency 50 / 60 / 400 Hz

Order Quantity No minimums, no maximums

750kVA

Max Power Rating

3ø

Delta & Wye

400Hz

50 / 60 / 400 Hz

0MOQ

No Minimums, No Maximums

Applications

Where Three-Phase Transformers Are Used

Wherever real power has to be converted, isolated, or distributed — the plant floor, the drive line-up, the building panel, and the interconnect.

Industrial Power Distribution

Step service voltage down to panel voltage and derive a grounded neutral on site.

Motor & Drive Power

Dedicated isolation and drive-isolation transformers for VFD and large motor line-ups.

Commercial Buildings

Lighting, HVAC, and receptacle panels fed from a three-phase service at the right voltage.

Renewable & Utility

Interconnect inverters, storage, and generation to distribution-level three-phase systems.

Keep Exploring

Explore More Custom Transformers

Parent Hub Custom Transformers The full range of custom magnetics we design and build — compare every transformer type in one place. Back to the hub

01 Current Transformers (CTs) Current transformers (CTs) for accurate metering, protection, and monitoring. 02 Flyback Transformers High-frequency designs for switch-mode supplies, EV charging, and industrial electronics. 03 High-Frequency Transformers Compact, low-loss transformers for switch-mode and high-frequency power conversion. 04 Isolation Transformers Galvanically isolated, electrostatically shielded designs for clean, safe power. 05 PDU Transformers Power distribution unit transformers for data centers and critical power. 06 Pulse Transformers Fast-edge pulse transformers for signal coupling, gate drive, and timing. 07 Step-Down Transformers Voltage conversion for machinery, imported equipment, and OEM gear. 08 Step-Up Transformers Boost lower input voltages to the higher levels your equipment requires. 09 Toroidal Transformers Low-noise, high-efficiency cores for audio, medical, and instrumentation. 10 Voltage / Potential Transformers (VTs/PTs) Voltage (potential) transformers for safe, accurate high-voltage measurement. 11 Guitar Amp TransformersCatalog Parts Available Output, power, and choke transformers for guitar amps — stock or custom. 12 Distribution TransformersCatalog Parts Available Single and three-phase distribution units up to 750 kVA. 13 Padmount TransformersCatalog Parts Available Pad-mounted transformers for commercial and utility sites.

Industries Served

From NASA payloads to guitar amplifiers, Pacific Transformer's custom magnetics power some of the most demanding applications in the world. Our engineering team has deep experience across industries where compliance, performance, and reliability aren't optional — they're required.

Aerospace

Defense

Medical & Dental

Automotive & EV

Audio

Conveyance Systems

Industrial & Commercial

Power Quality & Measurement

Alternative Energy

Data Center

Utilities

FREQUENTLY ASKED QUESTIONS

Three-Phase Transformers

A delta connection joins the three windings end to end with no neutral point, which suits three-wire loads and helps circulate triplen harmonics. A wye connection ties one end of each winding to a common neutral, giving you a fourth wire and a grounding reference for single-phase loads. Delta-wye is the most common distribution configuration because it does both — no neutral on the primary, a derived neutral on the secondary.

Yes. Where the ratio change is modest and galvanic isolation is not required — 480 to 400 V, or 480 to 208 V boost/buck applications — a three-phase autotransformer is smaller, lighter, and more efficient than an isolated unit. We will tell you when isolation is worth the size penalty and when it is not.

Yes. Specify the vector group (Dyn11, Dy1, Yy0, and so on) and we will wind to it, including designs with a deliberate 30-degree phase shift for twelve-pulse rectifier and harmonic-cancellation schemes.

No — no minimums and no maximums. We build from a single prototype through full production runs, with free engineering and a working prototype typically in 48 hours.

Send Us Your Specs

Specs in — a quote back in 24 hours.

Tell us what you're building. A Pacific Transformer applications engineer reviews every request and responds with pricing and lead time — no forms routed to a sales queue.

24HR

Quote turnaround

Pricing and lead time within 24 hours

48HR

Prototype turnaround

A wound, tested prototype in 48 hours

Prefer to talk it through? 800-325-0501

Buy Guitar Amp Transformers Direct