TP&C - NESC 2007 by W1NB3K

VIEWS: 0 PAGES: 10

									Significant Rejected
Change Proposals
        Nelson Bingel
  Osmose Utilities Services, Inc.

             January 9, 2007
                  Orlando
    Towers, Poles & Conductors Meeting
       Panel Session Part 2 Agenda
• Introduction of Rejected Change Proposals – Implications for 2012
                                                 (Nelson Bingel)

• CP 2766 – Remove 60 ft Extreme Exclusion       (Jerry Wong)

• CP 2780/2781- Incorporate ANSI-O5.1-2002       (Nelson Bingel)

• CP 2733/2734/2736 - Reliability-Based Design     (Larry Slavin)

• CP 2829 – Insulator Strengths (Ultimate vs. Working)
                                                 (Bruce Freimark)
• CP 2737 - Total Rewrite of Strength & Loading (Bob Peters)
    Overview of Other Rejected CP’s

   CP 2707 Eliminate the Additive Constant

   CP 2718 Simplify Extreme Wind Calculations

   CP 2658 Construction & Maintenance Loads

   CP 2768 Conductor Tension Requirements
CP 2707 Eliminate Additive Constant

   Early 1900’s
    – Heavy & Medium: 8 lb
    – Light: 12 lb
   5th Edition (1948)
    – Heavy & Medium: 4 lb
    – Light: 9 lb
    – Applied same wind to all components
    – Constant to increase resultant vertical and horiz.
      Conductor tension back to approx. 8 lb & 12 lb
CP 2707 Eliminate Additive Constant

   Confusion
    – Apply to conductor strength only
    – Or also for conductor tension at dead ends

   Proposal doesn’t change dead end
    requirement but clarifies code
   Proposal increases tension in light loading
    district
CP 2718 – Simplify X-Wind Calcs
    CP 2658– Construction & Maint.
               Loads
   Rule 250A2

   Two Load Cases

    – 2 Workers on Structure

    – Lockup of stringing block during installation of a
      wire or conductor
   CP 2658– Construction & Maint.
              Loads
   250A2. Where construction or maintenance loads exceed those
 imposed by Rule 250A1, which may occur more frequently in light
 loading areas, the assumed loadings shall be increased accordingly.
    When temporary loads such as lifting of equipment, stringing
   operations or a worker on a structure or its component, are to be
imposed on a structure or component, the strength of the structure or
 component should be taken into account or other provisions should
   be made to limit the likelihood of adverse effects of structure or
                          component failure.
  NOTE: Other provisions could include cranes that can support the
     equipment loads, guard poles and spotters with radios to, and
 stringing equipment capable of, promptly halt stringing operations.
      CP 2768 – Conductor Tension
             Requirements
   Rule 261.H.1
    – To address aeolian vibration
   Accept as Modified
    – Note: The above limitations may not protect the
      conductor or facilities from damage due to aeolian
      vibration.
Significant Rejected
Change Proposals
        Nelson Bingel
  Osmose Utilities Services, Inc.

             January 9, 2007
                  Orlando
    Towers, Poles & Conductors Meeting

								
To top