DECS-400, Digital Excitation Control System

The DECS-400 is a versatile digital excitation control system for synchronous generators and motors. It has the flexibility to be utilized for either exciter field applications or static exciter applications up to 2,500 Adc. This makes the DECS-400 ideal for new and retrofit applications. The DECS-400 can be provided in many configurations to meet specific requirements and redundancy needs. Basler offers customized and standard solutions engineered to meet a wide variety of applications.


  • A wide variety of redundancy options increases system reliability.
  • An available suite of limiters coordinates with protective functions to help maintain safe operating parameters and avoid system downtime.
  • Avoid system damage by utilizing various protection functions integrated into the controller.
  • Maximize excitation system performance with dual gain settings based on load conditions.
  • Improve system reliability and stability by coordinating dual settings groups for limiters and protection to match generation system conditions.
  • Prevents undesired overshoots using the soft-start feature to maintain generator voltage control during system startup.
  • Time-synchronizing provisions facilitate event analysis with a common chronological reference to aid in coordination efforts when comparing oscillography files from other devices.
  • Simplify system testing and commissioning with real-time monitoring and built-in test provisions.
  • Entering settings with confidence is easy with BESTCOMS™. Software provides intuitive settings with graphs, built-in error checking, and summary screens.
  • Sequence of Events and Oscillography Recording provisions collect valuable system data triggered by disturbances for event analysis.
  • Avoid costly generator damage and improve overall system stability with Basler Electric's integrated Power System Stabilizer (optional) that utilizes the "integral of accelerating power" to safely dampen local mode, inter-area and inter-unit power oscillations.
  • Basler's in-house engineering, fabrication, manufacturing, and test capabilities provide maximum control of processes and product design, resulting in the highest quality and maximum reliability while offering shorter lead times.


Technical Resources


Case Studies

  • Case Study

    • One Good DECS Deserves Another (616.8KB)
      Throughout Taiwan’s history, many government-owned power plants were built to supply power for the main island of Taiwan and its outlying islands. Basler excitation systems and protective relays are widely used in these plants.
    • One of Basler’s First SSE’s Still Carrying the Load of a 2MW Generator (1.8MB)
      From the early days of rotating exciters to today’s digital static excitation systems using power semiconductors, Basler’s generator excitation systems have made great strides in innovation and efficiency while always maintaining their reputation for legendary reliability.