Download as PDF, PPTX
![IEEE Standard 1584
Incident Energy Calculation for
Arc Flash in a Cubic Box
E =1038.7D-1.4738 x T[0.0093F2-0.3453F+5.9675]
E = Incident Energy in cal/cm2
D = Distance to arcing point
T = Time to clear arcing fault
F = Available bolted fault short circuit current](https://image.slidesharecdn.com/ppparcflashpresentationv5-1-120502225507-phpapp02/85/20120504-LISAT-slides-Dube-6-320.jpg)
![Arc Flash Mitigation
Incident Energy Calculation
E =1038.7D-1.4738 x T[0.0093F2-0.3453F+5.9675]
E = Incident Energy in cal/cm2
D = Distance to arcing point
T = Time to clear arcing fault
F = Available short circuit current](https://image.slidesharecdn.com/ppparcflashpresentationv5-1-120502225507-phpapp02/85/20120504-LISAT-slides-Dube-66-320.jpg)
More Related Content
Similar to 20120504 LISAT slides Dube
20120504 LISAT slides Dube
- 1. ARC FLASH MITIGATION STRATEGIES for METALCLAD SWITCHGEAR PEDERSEN POWER PRODUCTS Th Sign o Quality e f
- 2. Discussion Topics ArcFlash Standards Arc Flash Prevention Arc Flash Protection Mitigation Techniques
- 3. Arc Flash Hazards Molten Metal Intense Heat Droplets 35,000F Flying Objects & Shrapnel Toxic Gases Copper Solid to Intense Vapor Expansion Light Flash 67,000 Times Sound Blast Pressure Wave
- 4. ARC FLASH STANDARDS PEDERSEN POWER PRODUCTS Th Sign o Quality e f
- 5. IEEE Standard 1584 Containscalculations used to determine safe boundary distances for unprotected personnel and the incident energy at the working distance for qualified personnel working on energized equipment.
- 6. IEEE Standard 1584 Incident Energy Calculation for Arc Flash in a Cubic Box E =1038.7D-1.4738 x T[0.0093F2-0.3453F+5.9675] E = Incident Energy in cal/cm2 D = Distance to arcing point T = Time to clear arcing fault F = Available bolted fault short circuit current
- 7. NFPA-70E-2009 Standard for Electrical Safety in the Workplace Utilizes IEEE 1584 methods for calculating incident energy on specific electrical equipment and provides guidelines for the PPE clothing required based on the incident energy level.
- 8. National Electric Code Requireslabeling of electrical equipment to warn qualified personnel of the danger of electric arc flash. Refers to NFPA-70E as a guide for quantifying the hazard.
- 9. Arc Flash WarningLabel Compliance with National Electric Code
- 10. Arc Flash WarningLabel
- 11. OSHA 29 CFRPart 1910 1910.333 Selection and Use of Work Practices Safety-related work practices to prevent injuries resulting from either direct or indirect electrical contact, when work is performed near or on equipment or circuits which may be energized. 1910.335 Safeguards for Personal Protection PPE shall be used to protect employees from electrically related injuries while that employee is working near exposed energized parts. Subpart S, Appendix A References NFPA-70E for Electrical Safety Practices
- 12. ARC FLASH PREVENTION PEDERSEN POWER PRODUCTS Th Sign o Quality e f
- 13. Arc Flash Prevention DON’T WORK ON ENERGIZED ELECTRICAL EQUIPMENT!
- 14. Causes of ElectricArc Flash Contact with Live Parts Unsafe Work Procedures Misoperation Insufficient Maintenance Overvoltages Insulation Failure Entry of Small Animals
- 15. Arc Flash Prevention Maintain Sound Safety Practices Prevent Entry of Critters Use IEEE Metalclad Standards Prevent Moisture Ingress Proper Insulation System Design Monitor for Partial Discharge Monitor Bus Temperatures
- 16. IEEE Standard C37.20.7 “Thereis little likelihood of an internal arc in equipment meeting the requirements of IEEE Standard C37.20.1-2002 or IEEE Standard C37.20.3-2001. There is even less likelihood of an internal arc in equipment that has insulated bus, compartmentalization, barriers, and interlocks, such as those described in IEEE Standard C37.20.2-1999.” Metalclad Switchgear Design Standard
- 17. Metal Enclosed Switchgear Line Terminals Uninsulated Bus Load break air switch Everything in Same Compartment Exposed Live Parts with Fuse Door Open Load Terminals Ground bus
- 18. Metalclad Switchgear Relay, Controls Primary buses and and connections covered Instrumentation with insulation Shutters cover Main bus Primaries when Primary circuits, no breaker installed relays, meters, and controls isolated in own CT barrier CT grounded metal Load compartments bus Movable Shutters CT Breaker Compartment Ground bus
- 19. Metalclad Switchgear Relay, Controls and Instrumentation Main bus Steel barrier CT No primary circuits Load exposed with bus breaker installed Vacuum CT Breaker Ground bus
- 20. Arc Flash Prevention Maintain Good Safety Practices Prevent Vermin Entry Use IEEE Metalclad Standards Prevent Moisture Ingress Proper Insulation System Design Monitor for Partial Discharge Monitor Bus Temperatures
- 21. Moisture Prevention IEEETested Enclosure Design Use Extended Life Sealants IEEE C37.20.2 Section 6.2.10 Ventilate Test Criteria Cable Compartment 7.1 gallonsFilters/Screens rate • Maintain per minute flow 60psi Dualwater pressure • Use min Strip Heaters 10 ft. Min Distance from Joints • Monitor Strip Heaters Against 2 Surfaces at each Joint • Seal Unintentional Openings Apply Quality Protective Finish
- 22. Arc Flash Prevention Maintain Good Safety Practices Prevent Vermin Entry Use IEEE Metalclad Standards Prevent Moisture Ingress Proper Insulation System Design Monitor for Partial Discharge Monitor Bus Temperatures
- 23. Insulation Materials 95kV BIL Rated Insulators Fluidized Bed Epoxy Bus Insulation Cycloaliphatic bus supports PVC Insert
- 24. Arc Flash Prevention Maintain Good Safety Practices Prevent Vermin Entry Use IEEE Metalclad Standards Prevent Moisture Ingress Proper Insulation System Design Monitor for Partial Discharge Monitor Bus Temperatures
- 25. Partial Discharge Monitoring Signal sent to InsulGard RFCT #1 detects partial Relay discharges internal to switchgear compartment. RFCT #2 detects partial discharges in Customer’s cables up to 100 ft from switchgear
- 26.
- 27. Arc Flash Prevention Maintain Good Safety Practices Prevent Vermin Entry Use IEEE Metalclad Standards Prevent Moisture Ingress Proper Insulation System Design Monitor for Partial Discharge Monitor Bus Temperatures
- 28. Temperature Monitoring Bus Joint Wireless Parasitically Powered Temperature Detectors for Medium Voltage Switchgear Straight (under development) Bus
- 29. Output Through Internet Protectionsystem configuration Temperature input from sensors Current Input from CT’s Calculate and Predict a Problem Email/Alarm notification
- 30. ARC FLASH PROTECTION PEDERSEN POWER PRODUCTS Th Sign o Quality e f
- 31. Arc Flash Protection Train Personnel Wear Proper PPE Install Warning Labels Maintain Good Safety Practices Build Sturdy Enclosure Reduce the Human Interface Redirect the Blast Energy
- 32. Safety Practices De-EnergizeEquipment Use Lockout/Tagout Procedures Latch and Secure All Panels Label Line and Load Side Bus Isolate Potential Backfeeds Open Tie Breaker/Redundant Sources Ground De-Energized Conductors
- 33. Safety Practices IEEE C37.20.6-2007 G&T TESTING STANDARD First G&T Standard Established Formal G&T Tests BIL Withstand AC Hipot 1-minute Momentary For 10 Cycles Per C37.20.2 K*I 2 Seconds Per C37.20.2 Interlocking (Upper & Lower) 500 Insertions and Removals
- 34. Safety Practices Ball TypeGround & Test Device
- 35. Safety Practices Ground Conductor Sizing 25kA for 2 seconds Requires three (3) – 350mcm cables per phase (total of 9 grounding cables) Ground Conductor Sizing 31.5kA for 2 seconds Requires three (3) – 500mcm cables per phase (total of 9 grounding cables)
- 36.
- 37. Arc Flash Protection Train Personnel Wear Proper PPE Install Warning Labels Maintain Good Safety Practices Build Sturdy Enclosure Reduce the Human Interface Redirect the Blast Energy
- 38. Sturdy Enclosure Design Use Only 11 Gauge Steel Weld Cubicles Two Walls Between Sections Heavy Duty Door Hinges Heavy Duty Door Latches
- 39. Arc Flash Protection Train Personnel Wear Proper PPE Install Warning Labels Maintain Good Safety Practices Build Sturdy Enclosure Reduce Human Interface Redirect the Blast Energy
- 40. Reduce Human Interface Opening & Closing Breaker Relocate control switch Use remote communications Use local HMI Use remote control station Use Remote Operator Use Time Delay Control Switch
- 41. Reduce Human Interface Remote Breaker Control Smart Remote Control Station
- 42. Reduce Human Interface Remote Breaker Control ELECTROSWITCH
- 43. Reduce Human Interface Remote Breaker Racking Remote Breaker Racking Motor Remote Breaker Racking Motor
- 44. Reduce Human Interface Remote Breaker Racking
- 45. Reduce Human Interface Remote Breaker Racking
- 46. Arc Flash Protection Train Personnel Wear Proper PPE Install Warning Labels Maintain Good Safety Practices Build Sturdy Enclosure Reduce the Human Interface Redirect the Blast Energy
- 47.
- 48. IEEE Standard C37.20.7 Aprocedure for testing and evaluating the performance of medium-voltage metal-enclosed switchgear for internal arcing faults and identifying the capabilities of the equipment relative to specific zones of protection. NOT A DESIGN STANDARD
- 49. IEEE Standard C37.20.7 Arc-Resistant Definition: “Equipment designed to withstand the effects of an internal arcing fault as indicated by successfully meeting the requirements of IEEE Standard C37.20.7-2007.”
- 50. IEEE Standard C37.20.7 TermArc Resistant can be misleading. In the event of an internal arcing fault, the dangerous effects of the arc are vented away from the zone of protection for personnel. Term Arc Venting is more accurate
- 51.
- 52. Arc Venting Switchgear 48”min 95” Duct can exit to the left, right, or rear
- 53. Arc Venting Switchgear Exhaust Vent Duct Design Tested on the switchgear Must vent to safe area Fire rated at wall opening No external air allowed in Prevent buildup of ice and snow Prevent critter ingress
- 54. IEEE Standard C37.20.7 “Notintended to provide this additional degree of “Intended to provide an additional degree of protection to operating personnel who, in thenormal protection to the personnel performing normal performance of their duties, would be required to operating duties in close proximity to the equipment open enclosure doors or panels or otherwise alter the while equipment is operating under normal equipment from its normal operating conditions.” conditions”
- 55. IEEE Standard C37.20.7 IEEEdoes not require that metalclad switchgear to be manufactured to pass the IEEE Standard C37.20.7 Testing Procedures.
- 56. IEEE Standard C37.20.7 Zones of Protection
- 57. Zones of Protection Type 1 Switchgear with arc- resistant designs or features at the freely accessible front of the equipment only.
- 58. Zones of Protection Type 2 Switchgear with arc- resistant designs or features at the freely accessible exterior (front, back and sides) of the equipment only.
- 59. Zones of Protection Type 1B That arcing does not cause holes in the freely accessible front of the enclosure or in the walls isolating the low-voltage control or instrument compartments.
- 60. Zones of Protection Type 2B That arcing does not cause holes in the freely accessible front, sides and rear of the enclosure or in the walls isolating the low-voltage control or instrument compartments.
- 61. Zones of Protection Type 1BC Adds isolation from effects of an internal arcing fault between all adjacent compartments
- 62. Zones of Protection Type 2BC Adds isolation from effects of an internal arcing fault between all adjacent compartments
- 63. Arc Venting Switchgear Considerations Initial cost (up to 25% more) Need breaker lift device Must design room accordingly Must seal all cable entries Low voltage wiring protection Loss of protection if door/panel open
- 64. IEEE Standard C37.20.7 TestingDoes Not Address… Protection against toxic gases Protection against excessive sound Arcing within components Protection from above or below
- 65. ARC FLASH MITIGATION PEDERSEN POWER PRODUCTS Th Sign o Quality e f
- 66. Arc Flash Mitigation Incident Energy Calculation E =1038.7D-1.4738 x T[0.0093F2-0.3453F+5.9675] E = Incident Energy in cal/cm2 D = Distance to arcing point T = Time to clear arcing fault F = Available short circuit current
- 67. Arc Flash Mitigation Complete System Analysis High Speed Differential Relay Fast Bus Tripping Maintenance Relay Settings Arc Flash Detection Hi-Speed Arc Terminator 3 Cycle Breakers Current Limiting Fuses
- 68. Fast Bus Tripping 50/62 50 50 50 50 50 T
- 69. Fast Bus Tripping 50/62 T 50 50 50 50 50
- 70. Arc Flash Mitigation Complete System Analysis High Speed Bus Differential Relay Fast Bus Tripping Maintenance Relay Settings Arc Flash Detection Hi-Speed Arc Terminator 3 Cycle Breakers Current Limiting Fuses
- 71. Maintenance Relay Settings RelayGroup Settings Feature can be enabled by a contact input, communications or ARMs Selector Switch to enable “Maintenance Mode” protective settings when maintenance is being performed on the equipment. “Maintenance Mode” Protective Group settings typically establish lower instantaneous pick- ups that can be optimized to reduce trip delays and increase sensitivity, but avoid nuisance trips. Remote and/or Local Visual Indication can be provided to confirm the Relay is in Maintenance Mode. ARMs Selector Switch TB2 FP5000 Relay Maintenance Mode a b Indicating Light ARM’s Selector Switch FP5000 Postion A Position B Relay Settings Group 2 Group 1 Group Maintenance Mode Normal Mode CI - 7 Relay Contact CI - 8 CI-7 CI-8 Input
- 72. Arc Flash Mitigation Complete System Analysis High Speed Bus Differential Relay Fast Bus Tripping Maintenance Relay Settings Arc Flash Detection Hi-Speed Arc Terminator 3 Cycle Breakers Current Limiting Fuses
- 73. Arc Flash Detection Microprocessorbased high speed relay sends trip signal to breaker upon sensing a light flash with high speed light sensors installed in the switchgear compartments.
- 74. Arc Flash Detection SEL-751AFeeder Protection Relay Instantaneous Overcurrent Timed Overcurrent Instantaneous Neutral Overcurrent Times Neutral Overcurrent Undervoltage (Bus Side) Overvoltage (Bus Side) Undervoltage (Line Side) Overvoltage (Line Side) Over Frequency Under Frequency Syncronism Check Auto-Reclosing Arc-Flash Detection Arc-Flash Overcurrent
- 75. Arc Flash Detection TestCell Without Arc Flash Detection
- 76. Arc Flash Detection TestCell With Arc Flash Detection
- 77. Arc Flash Detection SwitchgearWithout Arc Flash Detection
- 78. Arc Flash Detection SwitchgearWith Arc Flash Detection
- 79. Arc Flash Detection TestDummy Without Arc Flash Detection
- 80. Arc Flash Detection TestDummy With Arc Flash Detection
- 81. Arc Flash Mitigation Complete System Analysis High Speed Bus Differential Relay Fast Bus Tripping Maintenance Relay Settings Arc Flash Detection Hi-Speed Arc Terminator 3 Cycle Breakers Current Limiting Fuses
- 82. Arc Terminator Detects presenceof an arc flash with high speed photo sensors and closes a high speed switch that shorts out the the main bus in the first ¼ cycle to create a parallel path to the arc and quickly extinguish a burning arc
- 83.
- 84.
- 85. Arc Terminator Phase B Phase C Phase A
- 86.
- 87. Arc Terminator ConfinesArc Effects at Initiation Point Extinguishes Arc < ¼ Cycle Prevents Pressure Buildup No Change to Relay Coordination Integrated Into Switchgear Lineup Indicates Where Flash was Detected. Limited to 40ka Symmetrical Faults
- 88. Arc Flash Mitigation Complete System Analysis High Speed Bus Differential Relay Fast Bus Tripping Maintenance Relay Settings Arc Flash Detection Hi-Speed Arc Terminator 3 Cycle Breakers Current Limiting Fuses
- 89. Arc Flash Mitigation Complete System Analysis High Speed Bus Differential Relay Fast Bus Tripping Maintenance Relay Settings Arc Flash Detection Hi-Speed Arc Terminator 3 Cycle Breakers Current Limiting Fuses
- 90. Current Limiting Fuses CurrentLimiting Protector (CLiP) Up to 5,000A Continuous @15.5kv Up to 120,000A Interrupting
- 91. Current Limiting Fuses 10ka Trigger Element limits peak to 17ka vs 48ka
- 92. Scheme Comparison 5 Cycle Breakers 3 Cycle Breakers Arcing Percent Arcing Percent Protection Scheme Time Reduction Time Reduction Normal Coordination 800ms 0% 767ms 0% Fast Bus Trip 170ms <79%> 137ms <83%> Maintenance Settings 120ms <85%> 87ms <89%> High Speed Differential 107ms <87%> 74ms <91%> Arc Flash Detection 86ms <89%> 53ms <93%> Arc Terminator 2.3ms <99.7%> 2.3ms <99.7%>
- 93. NFPA Personal Protective Equipment Requirements PEDERSEN POWER PRODUCTS Th Sign o Quality e f
- 94. NFPA PPE Requirements Incident Required Energy PPE Minimum Present Risk PPE Rating Protective Clothing Required to Prevent (cal/cm2) Cat (cal/cm2) Onset of a Second Degree Burn E ≤ 1.2 0 N/A Untreated Cotton 1.2 < E ≤ 4 1 4 FR Shirt + FR Pants 4<E≤8 2 8 Cotton Undergarments + FR Shirt + FR Pants 8 < E ≤ 25 3 25 Cotton Undergarments + FR Shirt + FR Pants + FR Coverall 25 < E ≤ 40 4 40 Cotton Underwear + FR Shirt + Pants + Multi-Layer Flash Suit (minimum of 3 layers) E > 40 N/A N/A Too Dangerous to Work On
- 95. NFPA PPE Requirements NO CALCULATION OF INCIDENT ENERGY NFPA Table 130.7(C)(9) – 1Kv – 38Kv Switchgear Tasks Performed on Energized Equipment Risk Cat Inspections Outside Restricted Approach Boundary 3 Operate Circuit Breaker with Door Closed 2 Operate Circuit Breaker with Door Open 4 Operate Meter Switch 0 Work on Energized Electrical Conductors 4 Work on Exposed Control Energized Circuits <120V 2 Work on Exposed Control Energized Circuits >120V 4 Racking of Breakers with Door Open or Closed 4 Application of Safety Grounds After Voltage Test 4 Remove Covers to Expose Energized Conductors 4 Open Hinged Covers to Expose Energized Conductors 3 Open PT or SST Compartment 4
- 96. NFPA PPE Requirements NO CALCULATION OF INCIDENT ENERGY NFPA Table 130.7(C)(9) – 1Kv – 38Kv Switchgear IF ARC RESISTANT SWITCHGEAR UTILIZED (for clearing times less than 500ms) Non AR AR Swgr Tasks Performed on Energized Equipment Risk Cat Risk Cat Operate Circuit Breaker with Door Closed 2 0 Operate Circuit Breaker with Door Open 4 4 Work on Energized Control Circuits <120V 2 0 Work on Energized Control Circuits >120V 4 4 Racking of Breakers with Door Open 4 4 Racking of Breakers with Door Closed 4 0 Insert or Withdraw Potential Transformers 4 0
- 97. E (cal/cm2) versusFault Current 5 Cycle Breaker Protection Scheme 25ka 40ka 50ka 63ka Normal Coordination 13.30 29.70 50.50 89.30 Fast Bus Trip 2.83 6.32 10.73 18.97 PPE E Maintenance Settings 2.00 4.46 7.58 13.39 (cal/cm2) Cat High Speed Differential 1.78 3.98 6.76 11.94 1.2 0 Arc Flash Detection 1.47 3.20 5.43 9.60 4 1 3 Cycle Breaker 8 2 Protection Scheme 25ka 40ka 50ka 63ka 25 3 Normal Coordination 12.75 28.5 48.40 85.60 40 4 Fast Bus Trip 2.28 5.09 8.65 15.29 >40 N/A Maintenance Settings 1.45 3.23 5.49 9.71 High Speed Differential 1.23 2.75 4.67 8.26 Arc Flash Detection 0.88 1.97 3.35 5.91
- 98. E (cal/cm2) versusDistance Normal Coordination (5 cycle) 100 90 PPE E 80 FC = 25ka (cal/cm2) Cat FC = 40ka 1.2 0 Incident Energy (cal/cm2) 70 FC = 50ka 60 FC = 63ka 4 1 50 PPE 8 2 Cat 40 25 3 4 30 40 4 20 >40 N/A 3 10 2 0 1 0 6 12 18 24 30 36 Distance to Arcing Point (inches)
- 99. E (cal/cm2) versusDistance PPE Normal Coordination (5 cycle) Cat 40 PPE 35 FC = 25ka E FC = 40ka 4 (cal/cm2) Cat FC = 50ka 30 1.2 0 Incident Energy (cal/cm2) FC = 63ka 25 4 1 20 3 8 2 15 25 3 10 2 40 4 5 1 >40 N/A 0 0 12 24 36 48 60 72 84 96 108 120 132 144 156 168 180 192 204 216 Distance to Arcing Point (inches) (216” = 18’)
- 100. E (cal/cm2) versusDistance PPE Bus Differential + Arc Flash (3 cycle) Cat 40 FC = 25ka 35 FC = 40ka 4 PPE E 30 FC = 50ka (cal/cm2) Cat Incident Energy (cal/cm2) FC = 63ka 1.2 0 25 4 1 20 8 2 3 25 3 15 40 4 10 >40 N/A 2 5 1 0 0 0 6 12 18 24 30 36 Distance to Arcing Point (inches)
- 101. Remote Racking/Control Advantages Normal Coordination (800ms clearing time) Standard 5 cycle Breakers Fault Operation at Front Operation at 20 Feet E PPE Current of Cubicle Door from Cubicle Door (cal/cm Cat 2) 2 25kA 8.31 cal/cm 0.51 cal/cm2 1.2 0 40kA 18.58 cal/cm2 1.13 cal/cm2 4 1 50kA 31.56 cal/cm2 1.93 cal/cm2 63kA 55.79 cal/cm2 3.40 cal/cm2 8 2 25 3 Bus Differential Protection (107ms interrupt) 40 4 Standard 5 cycle Breakers >40 N/A Fault Operation at Front Operation at 20 Feet Current of Cubicle Door from Cubicle Door 2 25kA 1.78 cal/cm 0.11 cal/cm2 40kA 3.98 cal/cm2 0.24 cal/cm2 50kA 6.76 cal/cm2 0.41 cal/cm2 63kA 11.94 cal/cm2 0.73 cal/cm2
- 102. Recommended Scheme Transformer Differential Protection Bus Differential Protection Arc Flash Detection To CT’s at Transformer 87T Zone 87B Zone Arc Flash Detection Zones
- 103.