Isolation Transformers

Johnson Electric Coil Company
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Our products are all made in Antigo, WI

Johnson Electric Coil Company provides complete design, engineering, and manufacturing services to supply our customers with the finest, most efficient and cost-effective single phase and three phase isolation transformers. Our isolation transformer design and manufacturing capabilities are some of the broadest in the industry. We can fully support our customer’s safety agency requirements with expertise in both domestic and foreign agency requirements.

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Single Phase Isolation Transformers

We design dry-type single phase isolation transformers to meet your custom requirements: high-reactance, ferro-resonant/constant-voltage, EI, toroid, special voltage requirements, taps where you need them, your choice of winding configurations, paper section or bobbin construction, special brackets, terminations to suit your installation, unusual sizes and
shapes—up to 75kVA.

Three Phase Isolation Transformers

We design dry-type three phase isolation transformers to meet your custom requirements: special voltage requirements, taps where you need them, your choice of winding configurations, terminations to suit your installation, unusual sizes and shapes—up to 250kVA.

Three phase transformer designs are carefully coordinated to meet your critical characteristics: electrical performance, terminations, size, weight, and price.

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The manufacture of three phase isolation transformers for high power and/or high current applications requires sophisticated testing, often using our state-of-the-art multi frequency generator.

Quality & Service

Our products are all made in Antigo, Wisconsin USA

In addition to our specialty engineering and manufacturing services, we work with our customers to customize scheduling, packaging, shipping, billing, and communication practices to meet their unique inventory management, product handling, delivery, and customer service needs. Our goal is to provide a level of quality and service that enables our customers to be leaders in their markets. While we mainly sell in the US, our single phase isolation transformers and three phase isolation transformers are found all over the world as components in OEM equipment. We pride ourselves on being the only transformer company our customers need.

Unified | Unselfish | Single Minded

Outstanding Customer Service

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We are happy to answer any questions you may have.
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