National Electric Coil


  National Electric Coil
800 King Avenue
Columbus, Ohio 43212
Phone:  +1 614-488-1151
FAX:  +1  614-488-8892National Electric Coil
3330 East 14th St
Brownsville, Texas 78521
Phone: +1 956-541-1759
FAX: +1 956-541-1759  

NEC is unique in its on-site capabilities to manufacture 
and insulate
copper wire to design specifications,
greatly reducing production lead times.


Automated taping machines speed manufacture with the simultaneous application of multiple layers of groundwall insulation.


Heated hydraulic cure presses fitted with tooling that
is unique to
each winding design.


A dummy core check is done several times during
manufacturing to assure proper fit and alignment.
Shown in this dummy core are inner liquid-cooled
stator bars.


The stator winding is the most critical component of a large power generator. With a proven track record and an unsurpassed product offering, NEC is widely recognized as the “Preferred Supplier” for High-Voltage stator coils for major rebuilders of power generation equipment.

NEC High Voltage Stator Winding Products

Well-known as the world leader, NEC has over 11,500 square meters of manufacturing space dedicated to high voltage coils and bars. As part of its service, NEC redesigns windings for machines of any OEM design or vintage. This includes stator windings of all types for units up to and exceeding 1000 MW. NEC’s stator winding products range from diamond coils and Roëbel bars to the most sophisticated direct-cooled bars, including both inner liquid- and gas-cooled types. NEC also specializes in the manufacture of windings for “legacy” or discontinued brands. Currently NEC produces over 15,000 stator coils a year under an ISO 9001:2000 certified quality management system.

Expertise & Experience

Many of NEC’s engineering staff of 24 began their careers with various OEMs and have advanced degrees specializing in Power and Machine Design. In addition to support for our High Voltage coil product lines and major uprates, NEC engineers are also actively involved with industry conferences and technical committees for various professional organizations, including EPRI, CIGRE, IEEE and ASME, among others.

NEC’s Design Difference & Experience Get the Job Done Right even on the largest machines!

  • Ability to re-optimize hydraulic cooling designs for water-cooled units.
  • Experience in bending and forming complex shapes, wire and tube configurations for inner gas cooled units.
  • Technical understanding of the dynamics of sympathetic resonance in large stator winding end turn structures.
  • Thorough knowledge of current issues related to PD and bar sparking in large air cooled generators.
  • Expertise in re-conditioning of individual bars for emergency repairs.

NEC Has the Ability to Execute on Time & Within Budget!

  • NEC’s Texas manufacturing facility is the largest most well-equipped of its kind in the world. Its equipment and staff is exclusively dedicated to HV windings.
  • NEC has OEM level engineering, production, project and service management staff with extensive experience on a wide variety of machines.
  • NEC’s High Voltage coil products deliver OEM equivalent resources at a value unsurpassed by others


NEC National Electric Coil • 800 King Avenue • Columbus, Ohio 43212 • Phone: +1 614 488 1151 • +1 614 488 8892
Copyright ©2009 National Electric Coil, all rights reserved