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2012 NESC. SCHEDULESEPTEMBER 1, 2009- Preprint publishedMAY 1, 2010- The final date to submit comments on the submitted change proposals and the subcommittee recommendations.. 2012 NESC. SCHEDULESubcommittees will meet in 2010 to consider all submitted commentsFinal ballot distributed to Main Committee and ANSI - Jan 15th, 20112012 Edition published on August 1, 2011Effective January 1, 2012.
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1. NATIONAL ELECTRIC SAFETY CODE
(ANSI C2 / NESC)
2. 2012 NESC SCHEDULE
SEPTEMBER 1, 2009- Preprint published
MAY 1, 2010- The final date to submit comments on the submitted change proposals and the subcommittee recommendations.
3. 2012 NESC SCHEDULE
Subcommittees will meet in 2010 to consider all submitted comments
Final ballot distributed to Main Committee and ANSI - Jan 15th, 2011
2012 Edition published on
August 1, 2011
Effective January 1, 2012
4. 2012 NESC SCHEDULE
November, 2011: John Pierson Jr. gathers his band of code warriors to begin preparations for “The 2012 Traveling Code Show” !
JP Jr’s Traveling Show headlines in March of 2012 and ends sometime thereafter.
Band Leader retires shortly after last show?!
5. 2012 NESC COMMITTEE STRUCTURE
Main Committee
Executive Committee
Subcommittee 1 –Purpose, Scope, Application, Definitions, and Reference
Subcommittee 2 –Grounding Methods
Subcommittee 3 –Electric Supply Stations
Subcommittee 4 –Overhead Lines –Clearances
Subcommittee 5 –Overhead Lines –Strength and Loading
Subcommittee 7 –Underground Lines
Subcommittee 8 –Work Rules
Interpretations Subcommittee
6. 2012 NESC FOUR PARTS TO THE NESC
• Part 1 – Rules for the Installation of Electric Supply Stations and Equipment
• Part 2 – Safety Rules for the Installation and Maintenance of Overhead Electric Supply and Communication Lines
• Part 3 – Safety Rules for the Installation and Maintenance of Underground Electric Supply and Communication Lines
• Part 4 – Rules for the Operation of Electric Supply and Communications Lines and Equipment
7. 2012 NESC
RUMOR HAS IT,
THERE WILL BE CHANGES IN
2012!
8. 2012 CODE Part 2:
Affecting Rule 230B (clearance section) and Rule 251B (loading section). Table 230-2 & Table 251-1
Both rules contain values for an additive constant (K factor).
Proposed change is to delete K factor and increase wind pressure from 4-lb to 6 - 8 lb
9. Wind Conversion:
From Code Table 250-4
40 mph = 4.0 lb/sq ft
50 mph = 6.4 lb/sq ft
60 mph = 9.2 lb/sq ft
Calculated = 8 lb’s/sq ft = 58 mph
10. 40% Initial 0o w/ice, 12% initial at 60o
11. 40% Initial 0o w/ice, 12% initial at 60o
12. 40% Initial 0o w/ice, 12% initial at 60o
13. 40% Initial 0o w/ice, 25% Final 0o (alcoa)
14. 40% Initial 0o w/ice, 25% Final 0o (alcoa)
15. 40% Initial 0o w/ice, 25% Final 60o(nesc)
16. 40% Initial 0o w/ice, 25% Final 60o(nesc)
17. 2012 CODE Part 2:
Affecting Rule 250C (Extreme wind loading) and Rule 250D (extreme ice with concurrent wind)
Proposed change is to eliminate the 60’ exclusion (required for all poles). Change was rejected but continues to be pain in our….
18. 2012 CODE Part 2:
Affecting Rule 215C5b regarding guy insulator placement. Some confusion on previous wording. No consensus by Interpretations Subcommittee.
There will likely be some word changing to clarify the rule.
19. 2012 CODE Part 3:
Affecting Rule 350F – Requires urd cable be marked with a lightning bolt symbol for power and a handset for communications.
Proposal recommends APWA Color Code as an additional method of identifying cables.
20. 2012 CODE Part 3:
Affecting Rule 384C – bonding requirements between above ground metallic power and communications apparatus (if <6’). Some confusion if comm. ped “contains” some metal apparatus inside.
Proposal to change the wording to eliminate the confusion.
21. 2012 CODE Part 4: Rule 410A3
Arc Exposure (2007 NESC)
Effective as of January 1, 2009, the employer shall ensure that an assessment is performed to determine potential exposure to an electric arc for employees who work on or near energized parts or equipment. If the assessment determines a potential employee exposure greater than 2 cal/cm2 exists, the employer shall require employees to wear clothing or a clothing system that has an effective arc rating not less than the anticipated level of arc energy……..
22. 2012 CODE Part 4: Rule 410A3
Arc Exposure (2007 NESC)
EXCEPTION 2: For secondary systems below 1000V, applicable work rules required by this part and engineering controls shall be utilized to limit exposure. In lieu of performing an arc hazard analysis, clothing or a clothing system with a minimum effective arc rating of 4cal/cm2 shall be required to limit the likelihood of ignition.
23. 2012 CODE Part 4: Rule 410A3
Proposed Changes
Clarify some of the language:
Interpretation Rule (IR 557) was published to help clarify “working on or near” and “potential exposure” language. Likely see some verbiage changes in this Rule.
24. 2012 CODE Part 4: Rule 410A3
Proposed Changes
EXCEPTION 2: For secondary systems below 1000 V, applicable work rules required by this part and engineering controls shall be utilized to limit exposure. In lieu of performing an arc hazard analysis, clothing or a clothing system with a minimum effective arc rating of 4 cal/cm2 shall be required to limit the likelihood of ignition.
25. 2012 CODE Part 4: Rule 410A3
Proposed Changes
26. 2012 CODE Part 4: Rule 410A3
Proposed Changes
(Footnotes Table 410-1)
1. This table is based on maximum fault current of 51kA.
Calculations are based on an 18-in separation distance from the arc to the employee. See IEEE 1584-2002.
Other methods are available to estimate arc exposure values and may yield slightly different but equally acceptable results.
The use of the table in the selection of clothing is intended to reduce the amount or degree of injury but may not prevent all burns.
27. 2012 CODE Part 4: Rule 410A3
Proposed Changes
(Footnotes Table 410-1)
2. Industry testing by two separate major utilities has demonstrated that voltages 50 -240V will not sustain arcs for more than 0.5 cycles thereby limiting exposure to less than 4 calories/cm2.
28. 2012 CODE Part 4: Rule 410A3
Proposed Changes
(Footnotes Table 410-1)
4. Industry testing on 480V equipment indicates exposures for self-contained meters do not exceed 20 calories/cm2.
29. 2012 CODE Part 4: Rule 410A3
Proposed Changes
(Footnotes Table 410-1)
5. Industry testing on 480V equipment indicates exposures for CT meters and control wiring does not exceed 4 calories/cm2. .
30. 2012 CODE
Questions?