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S-Series Toroidal Isolation Transformers
High-power toroidal isolation transformers up to 65kVA (65,000 VA) single phase, custom engineered in the USA for medical devices, industrial systems, audio, and precision equipment.
Custom S-Series Toroidal Power and Isolation Transformers
Since 1986, Bridgeport Magnetics and its Tortran division have designed and manufactured premium toroidal isolation transformers and power transformers for demanding applications. Our S-Series focuses on larger, high-power toroidal designs that deliver superior electrical isolation, low noise, minimal electromagnetic interference (EMI), and excellent efficiency in a compact footprint.
These transformers are ideal for medical devices, industrial equipment, test and measurement systems, audio amplifiers, and other applications where clean, isolated power and reliability are essential. Every S-Series unit is built to your exact specifications in our Shelton, Connecticut facility, with fast U.S. lead times and full engineering support.
Why Choose S-Series Toroidal Isolation Transformers
Larger toroidal isolation transformers offer significant advantages over traditional laminated designs, including a continuous magnetic path that reduces core losses, stray fields, and audible noise while improving overall efficiency (often 95 to 98%). This makes them especially well-suited for high-power, space-constrained, or noise-sensitive installations.
For engineers and OEMs working with larger systems, the benefits include:
- Higher power density in a smaller, lighter package
- Lower EMI and cleaner power delivery for sensitive electronics
- Reduced heat generation and simpler cooling requirements
- Quiet operation ideal for medical and laboratory environments
- Superior electrical isolation and safety compliance
Specifications
| Parameter | Details |
|---|---|
| Power Ratings | Up to 65,000 VA (65 kVA) single phase Up to 350,000 VA three-phase (industrial) Up to 5,000 VA single-phase (medical) |
| Operating Frequencies | 60 Hz, 50/60 Hz, 400 Hz, or custom |
| Input Voltage | As specified, up to 690V |
| Output Voltage | As specified (step-up, step-down, or 1:1 isolation) |
| Insulation System | Class B (130°C) standard; higher classes available |
| Mounting & Hardware | Standard options plus fully custom |
| Design Options | Auto-resettable or non-resettable thermal protection (mandatory for medical) • Electrostatic shield • Magnetic shield • Custom leads, enclosures, mounting, and taps |
S-Series high-power toroidal isolation transformers shine in compact, low-noise, high-efficiency isolation applications.
Medical Devices & Healthcare Equipment
High-reliability isolation transformers for MRI and CT scanners, patient monitoring systems, surgical equipment, infusion pumps, diagnostic imaging, and IEC 60601-compliant medical devices.
Industrial Automation & Control Systems
Robust toroidal isolation transformers for motor drives, PLCs, industrial control panels, robotics, and precision manufacturing equipment that require low EMI and stable isolated power.
Test, Measurement & Laboratory Equipment
Precision isolation transformers for laboratory analyzers, test instrumentation, calibration systems, and sensitive measurement devices where low noise and clean power are critical.
Professional Audio & AV Systems
Low-noise toroidal isolation transformers for high-end audio amplifiers, recording studios, broadcast equipment, and professional AV installations that demand hum-free performance.
Data Center UPS & Critical Power Systems
High-power isolation transformers for UPS systems, data center power distribution, and critical backup power applications where efficiency, compact size, and reliable isolation are required.
Safety Standard Certifications:
- UL 506, UL 1561, UL 5085
- CSA C22.2 No. 66-1988
- EN61588-1, IEC61558-1
- UL Files: E140446, E178316
- Intertek File: 3051384
- CE Mark and RoHS compliant
Medical Applications: Our TIS Series (and S-Series medical variants) meet IEC 60601-1 Third Edition and equivalents (AAMI/ANSI/UL 60601-1, CSA C22.2 No. 601.1-M90, EN60601.1). Also designed to applicable sections of UL950, IEC950, UL813, UL1236, and many others.
Let's build yours to spec.
Custom magnetics engineered and manufactured in the USA. Tell us your requirements and our engineers will help.
Frequently Asked Questions
What is a toroidal isolation transformer and what is it used for?
A toroidal isolation transformer provides galvanic isolation between input and output while delivering clean power with low noise and minimal electromagnetic interference. The S-Series is commonly used in medical devices, industrial automation, test equipment, professional audio, and critical power systems.
What are the key specifications of the S-Series toroidal isolation transformer?
The S-Series offers up to 65kVA single phase (higher in three-phase), operating frequencies of 50/60 Hz or 400 Hz, input voltages up to 600V, Class B insulation (higher available), and multiple design options including electrostatic/magnetic shielding and thermal protection.
Are S-Series transformers suitable for medical applications?
Yes. Medical-grade S-Series toroidal isolation transformers include required thermal protection and are designed to meet IEC 60601-1 and related standards with low leakage current for patient safety.
Can Bridgeport Magnetics build custom high-power toroidal isolation transformers?
Absolutely. We specialize in fully custom S-Series designs up to 65kVA single phase. Our engineers work with you on voltage, frequency, shielding, mounting, and other requirements for your specific application.
What are the advantages of toroidal isolation transformers over traditional designs?
Toroidal transformers offer higher efficiency, lower EMI, reduced audible noise, smaller size, and lighter weight compared to laminated transformers – making them ideal for high-power applications up to 65kVA where space and performance matter.
What certifications do S-Series toroidal isolation transformers carry?
They are certified to UL 506, UL 1561, UL 5085, CSA, IEC 61558, CE, and RoHS. Medical versions align with IEC 60601-1 requirements. Full certification files are available upon request.
