Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

New Approaches for Maintenance Grounding in Medium Voltage Switchgear

2,044 views

Published on

Copyright AIST Reprinted with Permission. Presented at the 2013 Iron and Steel Technology Conference and Exposition (AISTech 2013). Maintenance grounding is a traditional and proven method for protecting electrical workers during medium voltage switchgear maintenance. When properly applied, it eliminates dangerous differences in electric potential, and can redirect harmful current during events such as unforeseen induced voltage from motors and generators, accidental bus contact with adjacent live parts, or human error that causes equipment to be re-energized.

Published in: Technology, Business
  • Be the first to comment

New Approaches for Maintenance Grounding in Medium Voltage Switchgear

  1. 1. New Approaches for Maintenance Grounding in Medium Voltage Switchgear Joe Richard Senior Marketing Specialist Schneider Electric David Mabius Engineering Manager Schneider Electric
  2. 2. Electrical Maintenance Standards OSHA 1910. 269 - Electric Power Generation, Transmission, and Distribution  OSHA Standard governing maintenance of Electrical Generation, Transmission, and Distribution Equipment.  States the conditions that must be met for a reasonably safe work environment. NFPA 70E – Handbook for Electrical Safety in the Workplace, 2012  Industry Standard for meeting the requirements of OSHA 1910.269.  Article 120 lays out six steps for creating an Electrically Safe Work Condition According to both standards, current carrying portions of electrical equipment must be considered live until they have been grounded and verified.
  3. 3. Hazards of Electrical Maintenance Human Error:  Misread/Outdated Drawings  Not following Lock Out/Tag Out Procedures  Improper Grounding  Dropped Tools  Original Installation Errors External Sources of Energy:  UPS  Renewable Energy (Solar, Wind)  Generators and Microturbines  Capacitor Banks
  4. 4. Traditional Methods Manual Grounding  Cable Clamps  Bus Bar Clamps  Ground Ball and Socket Clamps  Exposed to Live Conductors  Full PPE Ground and Test Device  Most are never maintained  Most users are untrained
  5. 5. Integral Grounding Switches Benefits  Allows for the grounding of conductors before switchgear panels are removed  Easy to use when designed with safety interlocks  Easy to secure  Time saved in Grounding Procedure  Reduced probability of human error
  6. 6. Integral Grounding Switches Quality Requirements  Tested and approved for available fault current  Effective bonding of switch to ground bus  Robust construction to withstand mechanical fault forces  Source of voltage indication (LLIs)  Safety interlocking
  7. 7. 52 52 52 52 Applications: Example 52 52 525252 O CC C C C C C C Fully Energized Utility 1 Utility 2
  8. 8. 5252 52 52 52 52 Applications: Example 52 52 52 O OC C C C O O O Open Circuit Breakers Utility 1 Utility 2
  9. 9. 5252 52 52 52 52 Applications: Example 52 52 52 O OC C C C O O O Open Disconnect Switches Utility 1 Utility 2
  10. 10. 52 52 52 52 52 52 52 Applications: Example 52 52O OC C C C O O O Close Grounding Switches Utility 1 Utility 2
  11. 11. 52 52 52 52 52 52 52 Applications: Example 52 52O CC C C C C C C Close Circuit Breakers Equipotential Zone Utility 1 Utility 2
  12. 12. Thank You Joe Richard Senior Marketing Specialist Schneider Electric David Mabius Engineering Manager Schneider Electric

×