Steve Kovach District Sales Engineer

Transcription

1 Steve Kovach District Sales Engineer Institute of Electrical and Electronics Engineers American Society of Safety Engineers 1

2 Electrical Hazards Electrical Hazards Shock Arc Flash Arc Blast 2 2

3 Arcing Fault Basics 35,000 F Radiant Heat & UV Speed of Light Copper Vapor: Solid to Vapor Expands by 67,000 times Molten Metal Pressure Waves Sound Waves Shrapnel 700 mph Hot Air-Rapid Expansion Intense Light 3 3

4 Arc Flash Energy Arc flash Energy Is Dependent On: Arcing fault duration or time to clear Speed of the overcurrent protective device Arcing fault current magnitude Available fault current Current-limitation can reduce 4 4

5 Personnel Hazards Associated with Arc Flash Second Degree Burn Threshold : 80ºC/175 ºF (0.1 sec), just curable burn Third Degree Burn Threshold: 96 ºC/205 ºF (0.1 sec), incurable burn Eardrum Rupture Threshold 720 lbs/ft 2 Lung Damage - Threshold lbs/ft 2 5 5

6 Close-up of Test Area 6

7 Arc Flash Testing - Test KA Symmetrical Available Fault 480V, 3 Phase 6 cycle STD 6 cycle opening Fault Initiated on Line Side of 30A Fuse 640A OCPD Non Current Limiting with Short Time Delay 30A RK-1 Current Limiting Fuse Size 1 Starter 7 7

8 Arc Flash Testing - Test 4 Click on videos 480V, 22.6kA Short-Circuit Current 640A NCL OCPD: 6 cycle Clearing Time 8 8

9 Test 4 Still Photos 9 9

10 Test 4 Still Photos 10 10

11 Test 4 Still Photos 11 11

12 Test 4 Still Photos 12 12

13 Test 4 Still Photos 13 13

14 Test 4 Still Photos 14 14

15 Test 4 Still Photos 15 15

16 Arc Flash Testing Results - Test 4 Sound ft. T2 > 225 C /437 F T3 50 C / 122 F P1 >2160 lbs/sq.ft T1 > 225 C / 437 F > Indicates Meter Pegged 16 16

17 Arc Flash Testing - Test KA Symmetrical Available Fault 480V, 3 Phase 601A. Class L Current Limiting Fuse Fault Initiated on Line Side of 30A Fuse 30A RK-1 Current Limiting Fuse Size 1 Starter 17 17

18 Arc Flash Testing - Test 3 Click on videos 480V, 22.6kA Short-Circuit Current 601A CL Fuse: Less Than 1/2 Cycle Clearing Time 18 18

19 TEST 3 Slow Motion 19

20 Test 3 Still Photos 20 20

21 Test 3 Still Photos 21 21

22 Test 3 Still Photos 22 22

23 Test 3 Still Photos 23 23

24 Arc Flash Testing Results - Test 3 Sound ft. T2 62 C / F P1 504 lbs/sq.ft. T1 T3 (No Change From Ambient) > Indicates Meter Pegged > 175 C/ 347 F 24 24

25 22.6 KA Symmetrical Available Fault 480V, 3 Phase 601A. Class L Current Limiting Fuse Arc Flash Testing - Test 1 30A RK-1 Current Limiting Fuse Fault Initiated on Load Side of 30A Fuse Size 1 Starter X 25 25

26 Arc Flash Testing - Test 1 Click on videos 480V, 22.6kA Short-Circuit Current 30A CL Fuse: Less Than 1/4 Cycle Clearing Time 26 26

27 Test 1 Still Photos 27 27

28 Test 1 Still Photos 28 28

29 Test 1 Still Photos 29 29

30 Test 1 Still Photos 30 30

31 Arc Flash Testing Results - Test 1 Sound (No Change From Ambient) T2 (No Change From Ambient) T3 (No Change From Ambient) P1 (No Change From Ambient) T1 (No Change From Ambient) 31 31

32 Current-Limitation: Arc Energy Reduction Test 4 Non-Current Limiting Test 3 Reduced Fault Current via Current-Limitation Test

33 Test 4 Test 3 Test 1 47 in. 5.8 cal/cm amp non current-limiting OCPD 6 cycles opening time 22 in. 1.6 cal/cm 2 KRP-C-601SP 601 amp current-limiting Class L Fuse 6 in cal/cm 2 LPS-RK-30SP 30 amp current-limiting Class RK1 Fuse Determined by IEEE 1584 Methods 33 33

34 Arc Flash Protection Boundary NFPA 70E Article 100 Definitions Boundary, Arc Flash. When an arc flash hazard exists, an approach limit at a distance from a prospective arc source within which a person could receive a second degree burn if an electrical arc flash were to occur. Informational Note: A second degree burn is possible by an exposure of unprotected skin to an electric arc flash above the incident energy level of 5 J/cm2 (1.2 cal/cm2). AFPB IE > <

35 Shock and Arc Flash Boundaries Equipment Arc Flash Boundary (AFB) Dependent on fault level and time duration. Must wear appropriate PPE Limited shock boundary: Restricted shock boundary: Qualified or unqualified persons* *only if accompanied by qualified person Qualified persons only Shock protection techniques and equipment Prohibited shock boundary: Qualified persons only - PPE as if direct contact with live part Note: shock boundaries dependent on system voltage level 35 35

36 Arc Flash Labels NFPA 70E! WARNING Arc Flash and Shock Hazards Appropriate PPE Required Failure to Comply Can Result in Death or Injury 34 inch Arc Flash Boundary 3 cal/cm 2 Flash Hazard at 18 inches 1 Hazard Risk Category 4 cal/cm 2 shirt & pants hard hat, safety glasses, FR rated faceshield 480 VAC Shock Hazard 42 inch Limited Approach 12 inch Restricted Approach 1 inch Prohibited Approach 500V Class 00 gloves, leather protectors Equipment Name: XYZ Motor Starter 36 36

37 Arc Flash Hazard Analysis Arc Flash Hazard Analysis. An arc flash hazard analysis shall determine the arc flash boundary, the incident energy at the working distance, and the personal protective equipment that people within the arc flash boundary shall use. What is required? A. Determine Arc Flash Boundary B. Determine the PPE (Arc Flash Hazard Analysis) C. Equipment Labeling 37

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