18-Pulse Autotransformer | 100 HP Rating | P23807

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SNC’s 18-pulse autotransformer is a heavy-duty, multi-phase transformer designed to effectively reduce harmonic distortion for variable frequency drive applications.

A variable frequency drive (VFD) is a type of motor controller that varies a motor’s frequency and supplied voltage in order to produce energy savings and greater efficiency.

Harmonic distortion can be detrimental Operation of the VFD and induce conductor and motor degradation. To ensure safe and reliable VFD operation, an 18-pulse autotransformer converts the disrupted raw power from a diesel engine into a wavelength that’s as pure as possible. A smooth wavelength, free of interruptions, results in a clean, reliable motor drive.

VFDs, and therefore 18-pulse autotransformers, are commonly purposed in applications with large drive motors requiring variable speed with variable torque, such as pumps, machine tools, blowers, conveyer systems, A/C motors and more. Industries range from mining to steel mills to marine and more.

What is an 18-pulse autotransformer?

Regardless of the industry or application, an 18-pulse autotransformer is a three-phase transformer that acts as a voltage regulator and is designed to continuously generate electrical pulses of constant amplitude and great velocity.

SNC’s 18-pulse autotransformer is a light, compact unit that offers a smaller footprint. Available with or without an enclosure, our rugged 18-pulse autotransformer also provides multiple aluminum busbar termination options in various sizes to meet your specific application requirements.

18-pulse autotransformer specs

  • 3-phase, 480V primary and 427V secondary
  • 60 Hz
  • 50 to 500 horsepower ratings
  • ETL UL 1561 certified
  • Aluminum windings (While SNC uses aluminum windings and busbars to save on manufacturing costs, a lighter-weight transformer with copper windings and busbars are available upon request.)
  • 180°C (356°F) for better insulation
  • Thermal switches, which are normally closed as an added safety measure

To request a quote or get more information on how SNC can meet your exact specifications with 18-pulse autotransformers, contact our team today.

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