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Updates on Code Revisions. 2016 EFCOG Electrical Safety Workshop. Upcoming Revisions. 2017 NEC to be published September 2016 2018 NFPA 70E – 2 nd Review of Proposals, comment resolution, and final votes – THIS WEEK, to be published September 2017
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Updates on Code Revisions 2016 EFCOG Electrical Safety Workshop
Upcoming Revisions • 2017 NEC to be published September 2016 • 2018 NFPA 70E – 2nd Review of Proposals, comment resolution, and final votes – THIS WEEK, to be published September 2017 • IEEE 1584 – to be released 2016- late -– Guide to Arc Flash Calculations
2018 NFPA 70EStandard for Electrical Safety in the Workplace 1. All references to other standards will be removed from mandatory text. 2. The DC shock table will be reduced to 50 volts, but the lower range will go from 50 to 300 volts. 3. The lower thresholds for hazardous energy will be implemented into Articles 320, 330, and 350 will be 50 Vac and 100 Vdc. 4. The exception to 130.2 has been removed. 5. Deleted references to SPGFCI introduced during first draft. 6. PC 32 Richard Waters reject. 7. Better clarification of Shock Hazard definition with informational note. 8. PC 31 Richard Waters reject. 9. Global change replacing short circuit current to available fault current with informational note to definition addressing batteries. 10. Defined Fault Current and Fault Current, Available, including an illustration.
2018 NFPA 70EStandard for Electrical Safety in the Workplace 11. Documented program must include inspection element. 12. Applying hierarchy of controls to risk assessments. 13. PC 153 Mark Scott reject. 14. Documented program must include investigation of near misses. 15. Minor changes to training for safe release but not much impact for us. 16. Article 120 major changes in format and content. 17. PC 158 Mark Scott reject. PC 145 Mark Scott reject. I did not capture the actions on other 120 PC by EFCOG members, but they may have been folded into the major overhaul of 120.
IEEE P1584 Final Report of Task Group ‘New Model Validation’ Chair – Dan Doan Vice Chair – Albert Marroquin Meeting at ESW on March 7, 2016
Membership • Scope • Meeting schedule • Summary of evaluation • Conclusions • Path Forward
Membership Dan Doan Chair Albert Marroquin Vice-Chair / Secretary, ETAP Jim Babcock Member Lloyd Gordon Member Ken Jones Member Wei Jen Lee Member Afshin Majd Member, EasyPower Vince Saporita Member, EATON Tom Short Member, EPRI Marcelo Valdes Member, GE Mike Lang IEEE/NFPA Collaboration Chair DaleepMohlaP1584 WG Chair Bruce McClung P1584 WG Vice Chair Jim Phillips P1584 WG Secretary
Scope • Review the new model, model basis, methods, data • Compare results to the existing 2002 model • Develop application guidance to be included in the text of the next edition of IEEE-201X for review by P1584WG
Summary of evaluation For details, see TG reports August 2015 and February 2016. Phase 1: Understanding of test results and data processing Phase 2: Creation of validation plan and comparison validation tools Phase 3: Comparisons against processed test results performed by IEEE/NFPA Collaboration Phase 4: Comparisons against IEEE 1584-2002 test results.
Examples: HCB configuration with graphing of box size, IE, and working distance:
Phase 3 • Model predictions were compared against all test results to determine the overall performance of the model • Outliers and incomplete test data points were reviewed • Final model development test data (subset of total test results) was agreed on with collaboration research team • Annex to report has 2 files, ‘Model Development’ data and ‘All Test’ data spreadsheets
Phase 4 • Final model release candidate was reviewed and compared with model development test data • Comparisons showed the proposed model has improvements over the 1584-2002 model: • HCB, HOA, and VCBB configurations are available • Continuous model between LV and MV • Arcing current variation is considered at MV • More enclosure sizes • Larger variable range especially gap • Results are less ‘over-conservative’, especially AFB at MV • Gap variable considered for entire voltage range
Range of Parameters • Voltage: 208V to 15kV (all configurations) • Frequency: 50 or 60 Hz • Bolted Fault: • 208-600V 500A to 106kA • 601V-15kV 200A to 65kA • Gap between conductors: • 208-600V 0.25 to 3 inches (6 to 76 mm) • 601V-15kV 0.75 to 10 inches (19 to 254 mm) • Working Distance: 12” minimum • Arc Flash Boundary: same as WD • Duration: no limits • Enclosures: Note: Width must be > (4 x Gap) • 208 - 600V 14x12 to 20x20 (inches) • >600V - 2.7kV 20x20 to 26x26 (inches) • >2.7 - 5kV 26x26 to 45x30 (inches) • >5 - 15kV 36x36 to 45x30 (inches)
Application Guidance • Use Average and Minimum Iarc calculations, determine the durations for both, find the IE’s, and pick use the higher value. (All configurations, all voltages) • Enclosure sizes – use closest size from table 8.2, or use a value in the range allowed by voltage for more detailed calculation. Also use deep/shallow selection for <600V. • Some guidance on selecting configurations (HCB vs VCB vs VCBB, for example)
Model Files The following documents/files go along with the report: DataSummary All Test.xlsx DataSummary Model Development.xls IARC Ratio at Different Voltage_1.xlsx IEEE1584 ExcelCalculator_Version 2.6.2_User Define.xlsm IEEE1584 ExcelCalculator_Version 2.6.2_User Define_M.xlsm
Conclusions • TG reviewed the proposed model in 17 modifications • Exceptions: • TG did not duplicate the regression analysis that provided the equation values • TG did not review equations for ‘HCB with CT no Tube’ (no test data provided)
Conclusions • TG consensus: If applied within valid parameter ranges, the proposed model will provide results which are consistent, in more applications than 1584-2002 • The new model is based on over 1800 test points with additional configurations • The new model corrects some anomalies in 1584-2002 such as discontinuity at 1kV • TG has completed its scope and submitted a detailed report to WG officers
There is room for improvement; more testing would be useful to determine effect of: • Range of enclosure sizes • Enclosure depth • Distance from arc to back of box • Larger and smaller gaps based on actual equipment • Larger working distances • Effect of actual equipment including contents • DC Future Research Recommendations
Working Groups 4 DOE Electrical Safety Handbook 2 Hazardous Energy Control 3 10CRF851 Flowdown, and Subcontractors 5 Risk Assessment per 70E-2015 1 DC Systems
Working Group 4 DOE Electrical Safety Handbook Lloyd Gordon, LANL Mike Hicks, Idaho DOE Eugene Santiago, BNL John Lacenere, PPPL
Working Group 2 Hazardous Energy Control Stephanie Collins, LBNL
Working Group 3 Electrical Safety Subcontractorsand 10CFR851 Flowdown Jeff Williams, NNSA, Los Alamos etc.
Working Group 5Risk Assessment Greg Christensen, INL
Working Group 1 DC Systems Leads Gary Dreifuerst, ex LLNL Stan Berry, ex Navy Alan Tatum, current ORNL Peter McNutt, NREL