Optima Transformer is a Texas-based manufacturer specializing in designing and producing high-quality transformers, including pole-mounted, pad-mounted, and power transformers for voltage levels from 2kV to 500kV. The company offers nationwide repair and testing services, leveraging global partnerships for cost efficiency while maintaining top standards.
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OTC Services, IncWith roots in Ohio Transformer’s 1946 founding, OTC Services remanufactures and repairs dry-type and liquid-filled transformers for industrial and utility customers, while also designing and building new units. Its Northern Ohio operation occupies a 100,000-square-foot facility with direct rail access and a 100-ton overhead crane, supporting work that ranges from shop repairs to field service. OTC became part of the SGB-SMIT Group in 2012, linking its transformer work to a group with more than a century of design and manufacturing history.LOUISVILLE, OH
SGB-SMIT USASGB-SMIT USA manufactures large, medium, distribution, cast resin, and dry-type power transformers, as well as custom medium-voltage switchgear. It also provides transformer and switchgear field, repair, testing, maintenance, commissioning, refurbishment, and installation services for utilities, industrial facilities, data centers, oil and gas, substations, and wind power.LOUISVILLE, OH
Southwest Electric CoFounded in Oklahoma City in 1946 by three brothers as an electric-motor repair shop, Southwest Electric Co. now designs and manufactures transformers and custom switchgear while providing nationwide electrical field services. After joining the SGB-SMIT Group in 2025, the company operates as SGB-SMIT USA, pairing 75 years of Southwest Electric experience with a global transformer manufacturing network. Its motor operations can repair equipment weighing up to 100 tons, a reflection of the heavy-duty work behind its service offering.LOUISVILLE, OH
Northeast Transformer Services, LLCNortheast Transformer Services remanufactures and repairs medium-voltage, oil-filled distribution transformers at its Preble, New York factory. The company says it processes more than 10,000 transformer repairs annually and rebuilds transformers to new-unit quality standards, returning previously damaged or obsolete units to customers.PREBLE, NY