Manufacturing Ready for Your Unique Project

Any cooling type
Any coil geometry
Any insulation type
NEC can make any type of coil for any type of generator!

National Electric Coil's Brownsville Manufacturing facility is one of the largest of its type in the world. The equipment, tooling and workforce support the ability to manufacture any type of stator winding for any type of machine, two-pole or salient pole, turbogenerator or hydrogenerator.

Each winding that comes through our factory is a highly-engineered, a "one-off" manufacture unique to the machine in which it will be installed. That makes our windings different from many other manufacturers and it means that when coils or bars arrive at your site for installation, they will fit in your machine the as expected.

We have invested considerable time, energy and capital in making sure that our systems and people are both capable of reliable, efficient production. That means we can easily and quickly reconfigure our production lines for the next unique project — your project!


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State of the art equipment and technically reliable processes are in use in our plant. These operations are under constant scrutiny under our ISO9001-certified Quality Management system. NEC has the engineering design and factory resources to make any type of stator coil. Our typical coils are:

  • NECCOBond – E Class F (155°C) insulation based on a Mica – Epoxy Resin VPI (vacuum  pressure impregnation) system.
  • NECCOPress I,II and III Class F (155°C) insulation system based on B -Staged (resin rich) technology.
  • NECCOSeal Green Coil System, Class F (155°C) insulation system designed for Global VPI Industrial Motor Applications.

Our goal: Customer Satisfaction is No. 1!

  • That's why we strive every day to make well-fitting windings that are unequaled by any other manufacturer in the world for quality and wind-ability.
  • That's why every coil or bar that leaves our factory is individually tested.
  • That's why we continue to carefully invest in automated and semi-automated equipment but retain and train the personnel needed for those operations where workmanship and quality might suffer under automation.

The above video shows one of our automatic taping machines in operation while applying the groundwall insulation to a double-tube-stack (DTS) 900° Roebel stator bar. Each of the 36 bars in this winding weighed approximately 500 pounds. This machine is capable of applying four layers of half-lapped insulating tape in one pass.


Even if our customers' specifications do not require it, we test every one of our coils and bars before they leave our factory. This is our own unvarying standard, but we are happy to integrate our customer's specifications for testing with our own. At the start of every project, we review the customer's specifications, required guide standards and performance parameters. These all become part of our winding design and quality plan that assures the integrity of the design during our manufacturing from start to finish.

Our Brownsville facility also includes a state-of-the-art Research & Development lab where we regularly test our insulating materials, resins and other important materials used in manufacturing. Here also, our engineers watch over long-term testing projects and research failures.

Pack & Shipping

Whether our windings are shipped across the country or overseas, our custom-built shipping containers protect them until they reach their destinations. Our shipping containers are built with special interior yokes to cradle each coil or bar. Special wraps and packing materials protect the outer finishes, especially in the gradient areas. Other types of interior packing or crate construction address the special challenges of overseas transport, such as excessive humidity or moving crates through a shipyard.

In-Process Checks a Must!
At every step of our manufacturing process, quality checks are made to assure the best workmanship. NEC's Brownsville factory utilizes ISO9001-certified quality management systems.
Every Coil or Bar Tested!
Every coil and bar undergoes both in-process testing and final testing before it leaves the factory. These "tests" include both specified electrical tests as well as various dimensional checks.
Uniform Shape Assured!
A coil or bar must be uniformly shaped in order to wind the machine properly and to avoid problems that may initiate corona during operation. Dummy cores are used to check critical clearances in the end turns and overall fit in the stator core. Multiple checks are made at different stages of manufacture.