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Utility & Power Industry Solutions
At Bridgeport Magnetics Group, we help utility operators restore power faster, meter with precision, and deliver smarter power solutions. Our Utility and Power Industry Solutions provide reliable temporary power restoration, advanced precision metering, and comprehensive power management that drive operational reliability and confident decision making across your entire network - empowering you to meet the evolving demands of the modern energy grid.
Field-Refined Solutions Engineered Exclusively for Utilities
Since 1982, our flagship Power-Back Temporary Power Restoration systems have helped utilities restore service to communities in hours rather than weeks after major storms and grid outages. We manufacture precision toroidal metering current transformers for revenue-grade billing and protective relaying, along with compact substation auxiliary transformers for SCADA, protective relays, battery chargers, and station service loads. Every product is custom-engineered and manufactured in our Shelton, Connecticut facility, giving utility engineers direct access to U.S.-based design, production, and quality control.
Utility and Power Industry Solutions
Flagship PowerBack and ultra-portable Trident toroidal autotransformers help utilities restore service in days rather than weeks after major storms and grid outages.
High-precision window-type metering current transformers in a full range of ratios and accuracy classes for electric utilities, co-ops, and municipal power authorities.
Compact toroidal auxiliary and control power transformers for utility substation applications — SCADA systems, protective relays, battery chargers, and station service loads.
Compact, efficient isolation transformers with toroidal cores potted in rugged, weatherproof enclosures — built for decades of unattended outdoor streetlight and area-lighting service.
Our Customers
Power-Back Temporary Power Restoration
Natural disasters can cause major delays to permanent infrastructure repairs. When hurricanes, ice storms, tornadoes, or flooding destroy utility poles, transformers, and distribution lines, affected communities can face weeks or months without electricity. The Power-Back temporary power restoration system solves this problem by replacing either one hot leg or the neutral, restoring service in days rather than weeks for homes and critical functions
Emergency and Disaster Recovery
Power-Back temporary power restoration systems are designed for rapid deployment after major storms and catastrophic grid damage. These portable toroidal autotransformers replace either one missing hot leg or the neutral in 120/240V or 120/208V services and can be field-installed by standard utility line crews using standard equipment.
The key advantage of Power-Back (and the lightweight Trident model) over conventional repair-in-place approaches is speed. Whether the fault is a downed overhead conductor or a buried underground cable requiring time-consuming location and excavation, Power-Back units restore full service in days rather than weeks to residential homes, commercial buildings, industrial facilities, and critical infrastructure while permanent repairs proceed on a parallel track.
Typical deployment scenarios include:
- Hurricane aftermath – restoring power to residential homes and businesses with a single lost phase
- Ice storm recovery – temporary service for commercial and industrial sites after downed conductors
- Tornado damage – bridging outages at affected houses and facilities from lost phase
- Flood recovery – restoring service to locations with underground cable faults
- Wildfire restoration – rapid power restoration for residential and critical facilities after single-phase loss
Rapid Field restoration & Lineman tools
Beyond emergency applications, Power-Back temporary power restoration systems serve as essential everyday tools for utility line crews and cable technicians. These portable toroidal autotransformers replace either one missing hot leg or the neutral in 120/240V or 120/208V services and can be installed in minutes at the meter base using standard utility equipment.
Linemen rely on Power-Back and the lightweight Trident model to maintain service continuity for individual customers during planned work. Instead of leaving a single home, business, or facility without power while locating underground cable faults or performing routine service repairs, crews quickly restore full 120/240V service while permanent fixes proceed on a parallel track.
Key applications include:
- Service drop and secondary cable repairs – restoring single-leg outages at the meter base
- Underground lateral cable faults – keeping customers powered during location and excavation
- Meter base and service entrance work – rapid temporary service for planned maintenance
- Commercial, industrial & EV charging stations – minimizing downtime from single-phase interruptions
How It Works
Power-Back temporary power restoration systems are high-efficiency toroidal autotransformers designed for fast, safe installation at the customer meter base. Each unit is sized for common 100 A to 400 A services and engineered to replace either one missing hot leg or the neutral in 120/240V or 120/208V single-phase 3-wire systems.
Key components include:
- Precision toroidal core and windings for compact, lightweight performance
- Weatherproof enclosure with wheeled cart or lightweight Trident carry-in design
- Meter adapter or direct-wiring (CAM-Lock) connectivity for quick field connection
- Integrated circuit breaker with thermal protection for safe operation
Deployment is straightforward and fast: utility crews position the unit at the meter pan, connect using the meter adapter or direct wiring to the remaining good conductors, follow the proper breaker sequence, reinstall the customer meter, and energize. Full balanced 120/240V service is restored in minutes while permanent repairs continue on a parallel track.
All Power-Back and Trident units are manufactured by Bridgeport Magnetics in Shelton, Connecticut, and built to meet applicable utility safety and performance standards.
Metering Current Transformers
Accurate current measurement is essential for utility revenue metering, load management, and protective relaying. Metering current transformers (CTs) step down high primary currents into standardized secondary signals that meters and relays can process safely and accurately. Bridgeport Magnetics engineers and manufactures precision window-type toroidal metering CTs. Every unit is produced in our Shelton, Connecticut facility, tested to applicable ANSI and IEEE standards, and backed by full U.S. manufacturing traceability.
Accuracy Classes and Standards
Metering current transformers are classified by accuracy class, which defines the maximum allowable ratio error and phase angle error at specified burden and current levels. Bridgeport Magnetics manufactures high-precision window-type toroidal metering CTs to meet the accuracy and reliability requirements of North American utilities.
Revenue metering accuracy classes include:
- 0.15% extended-range accuracy class — the high-accuracy option for critical billing applications, wholesale interchange points, and large industrial accounts where even small errors have significant revenue impact.
All Bridgeport Magnetics metering CTs are manufactured and individually tested to applicable IEEE C57, ANSI, and NEMA standards. Full test reports are available upon request.
Revenue Metering Applications
Revenue metering CTs are the instruments that determine how much electricity a utility bills its customers – and how much it pays or receives at wholesale interchange points. Accuracy is not optional; it is a regulatory and financial requirement for billing and payments.
Bridgeport Magnetics’ precision window-type toroidal revenue metering CTs are designed for:
- Service entrance metering at commercial and industrial customer locations
- Substation revenue metering at transmission-distribution interfaces
- Wholesale interchange metering between utilities, ISOs, and power marketers
- Net metering for distributed generation installations
- Power quality monitoring where precise current measurement is required
Each CT is manufactured with tight control over core material properties, winding uniformity, and burden rating. The toroidal core construction ensures consistent, high-accuracy performance across the full operating range – from light-load conditions through full-load and moderate overload. For high-accuracy wholesale and large-customer metering, our 0.15% extended-range class CTs deliver the precision that interchange billing and critical revenue applications demand.
Protective Relaying & Monitoring Applications
Protective relaying CTs provide accurate current signals to protective relays so they can detect and clear faults quickly and safely. While Bridgeport Magnetics specializes in high-precision revenue metering CTs, our toroidal designs are also used in many low-burden protective relaying and power-quality monitoring applications.
The toroidal core construction delivers excellent transient response and low flux leakage, helping relays receive clean, undistorted current waveforms during normal operation and moderate fault conditions. Bridgeport Magnetics window-type metering CTs are frequently specified for:
- Substation control and monitoring circuits
- Protective relaying where relay burden is low
- Power quality and disturbance monitoring systems
- Backup or supplementary relaying at service entrances and industrial sites
For applications requiring both revenue-grade metering accuracy and reliable signal reproduction for relays, our 0.15% extended-range toroidal CTs often satisfy both needs without compromise.
Built for the grid. Proven in the field.
Toroidal power solutions engineered, tested, and manufactured in Shelton, Connecticut — trusted by utilities across North America.
Certifications & Standards for Utility Applications
Utility procurement is standards-driven. Every component installed on the grid must meet specific performance, safety, and accuracy standards. Each of those standards must be documented and verifiable. Bridgeport Magnetics designs all utility products to meet or exceed applicable standards from the outset.
IEEE Standards Compliance
Bridgeport Magnetics utility products comply with key IEEE standards for instrument transformers:
IEEE C57.13 - Standard Requirements for Instrument Transformers. This is the governing standard for metering current transformers used in revenue metering applications. It defines accuracy classes, burden ratings, thermal ratings, and test requirements.
IEEE C57.13.6 - Standard for High-Accuracy Instrument Transformers. This applies specifically to our 0.15% extended-range class CTs used at wholesale metering points and critical billing positions.
ANSI Metering Accuracy Standards
Bridgeport Magnetics metering current transformers are manufactured and tested in full compliance with the key ANSI standards for revenue metering systems:
ANSI C12.20 — Standard for Electricity Meters (0.2 and 0.5 Accuracy Classes).
ANSI C12.1 — Code for Electricity Metering. This standard defines metering installation practices and accuracy requirements that directly influence CT specifications and performance.
UL and CSA Certification
Bridgeport Magnetics maintains UL and CSA certification for applicable transformer products:
◦ UL Listed products carry the UL mark, confirming compliance with applicable UL safety standards for transformers
◦ CSA Certified products meet Canadian Standards Association requirements for sale and installation in Canada
◦ EN and IEC compliance is available for products destined for international utility markets
All certifications are maintained through ongoing factory audits and production testing. Certification documentation, test reports, and compliance letters are available upon request for utility procurement qualification packages.
Frequently Asked Questions
What accuracy class do your metering current transformers meet?
Bridgeport Magnetics manufactures high-precision window-type toroidal metering current transformers with a focus on revenue-grade accuracy. Our CTs are available with 0.15% extended-range accuracy class — the high-accuracy option preferred for critical billing applications, wholesale interchange points, and large industrial accounts.
All units are manufactured and individually tested to applicable IEEE C57, ANSI, and NEMA standards. The specific accuracy class and ratio are chosen based on your application requirements. Contact our engineering team with your metering needs, and we will recommend the optimal CT configuration.
What is the Power-Back temporary power restoration system?
The Power-Back temporary power restoration system is a portable toroidal autotransformer designed for rapid field deployment after storms and grid outages. It replaces either one missing hot leg or the neutral in 120/240V or 120/208V single-phase 3-wire services, quickly restoring full balanced power to homes, businesses, and critical facilities.
Utility line crews can install the wheeled Power-Back or lightweight Trident model at the customer meter base in minutes using standard equipment. This allows service to be restored in days rather than weeks while permanent repairs continue on a parallel track. Learn more on our Power-Back temporary power restoration product page.
Can you manufacture custom current transformers for our specifications?
Yes. Bridgeport Magnetics designs and manufactures custom window-type toroidal metering current transformers to your exact specifications. We can engineer CTs to your required ratio, 0.15% extended-range or standard accuracy class, burden rating, insulation level, physical dimensions, and other performance needs.
Our engineering team works directly with utility engineers and procurement teams from initial specification through prototype validation and production. Other ratios are available, and full test reports are provided with every unit.