ABB Power Services

Our aim is to increase systems reliability and extend the life of their equipment with concomitant gains for our customers’ competitiveness. We support our customers with high-quality services in preventive and corrective maintenance to improve risk mitigation and improved safety. ABB's service portfolio allows utilities and industrials to maximizing the return on all assets by ensuring a high reliability, reducing life cycle costs and ensuring optimized performance while lowering environmental impact.

Tuesday, October 18, 2011

Why retro-fill a medium voltage circuit breaker cell?

L-Frame Style Retro-fill

 
 
Module Style Retro-fill
 


Important Facts to consider:
 
 
Material safety

  • Early model medium voltage circuit breakers from various manufacturers contained asbestos arc chutes
  • Some manufacturers also incorporated as many as three mercury-filled switches in their breaker cell design
  • Asbestos and mercury are known hazardous materials to humans


Operational safety

  • The process of racking a circuit breaker into and out of the connected position is one of the most frequent exercises that expose an operator to risk.
  • Supervised, closed door circuit breaker racking is a fundamental recognized safety practice. Furthermore, older breakers are more complex and vulnerable to mechanical failures that create safety problems.


Remote racking limitations

  • Some manufacturers have engineered remote racking devices to provide unsupervised, remote connecting and disconnecting of the circuit breaker at some distance from the breaker cell.
  • The safety issues of asbestos and mercury exposure during maintenance associated with early vintage medium voltage circuit breakers and circuit breaker cells are not addressed.
  • A retro-fill solution removes personnel from exposure to these hazardous substances and provides closed door racking.


Roll-in replacement breakers

  • Some owners have identified vertically connected breakers as a potential hazard and are searching for solutions, short of switchgear replacement.
  • A breaker retro-fill converts the cell to a horizontal connected breaker, adds newer breaker technology and provides closed door racking.
  • Most owners have a wide variety of switchgear in their plants from various manufacturers.
  • Recognizing that this variety requires a similar variety of replacement parts, it further complicates maintenance training and can cause confusion.
  • Inadequate training and confusion can lead to serious safety issues.
  • A retro-fill solution provides a single current production circuit breaker across a variety ABB Inc. in manufacturer’s switchgear.

For more information about  Retrofill and Roll-in Replacement Breakers, please contact: www.abb.us/mvservice or call: 1 800 HELP 365 (Option 7) or +1 407 732 2000

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