Arc Flash: What's New in Codes, Standards and Solutions Papers/1117_arc_flash_new_standards_eaton.pdfIEEE 1584-2002 Guide for Performing Arc Flash Calculations July 2017 Draft Ballot

© 2017 Eaton Corporation. All rights reserved.

Arc Flash: What's New in Codes,Standards and Solutions

Electrical Systems: Design - Install - Maintain

David B. DurocherGlobal Industry Manager

Mining & MetalsEaton Corporation

Wilsonville OR [email protected]

November 2017

2 2

Arc Flash & PPE

Protection From Shock & Flash Hazards

An Arc Flash - An electrical arc due to either aphase to ground or phase to phase fault. Causedby many factors - dropped tools, improper workprocedures, etc.

80 percent of all electrical injuries are burnsthat result from the electric arc flash

Arc flashes cause electrical equipment toexplode, resulting in an arc-plasma fireball

Solid copper vaporizes, expands to 67,000times its original volume

Temperatures exceed 19,000 degrees C Detected sound levels of 141.5 decibels Pressure levels of 10,540 Kg per square

meter

3 3

NFPA70E-2018 Standard for Electrical Safety in theWorkplace: (US) and CSA Z462-2018 (Canada)

Quantifies Heat Energy from arc flash in calories/cm2

Recommends fire rated clothing: Personal ProtectiveEquipment (PPE) used during energized work

Recommends study update every 3 years

Standards Addressing Arc Flash HazardsElectrical Workplace Safety

Arc Flash Calculations IEEE 1584-2002 “Guide for Performing Arc

Flash Calculations” It presents formulas for numerically

quantifying heat energy from arc-flash

Includes an Excel Spreadsheet “Arc-FlashHazard Calculator” that performs calculationsusing heat energy formulas

4 4

NFPA70E-2018 Standard for Electrical Safety in theWorkplace: (US) and CSA Z462-2018 (Canada)

Quantifies Heat Energy from arc flash in calories/cm2

Recommends fire rated clothing: Personal ProtectiveEquipment (PPE) used during energized work

Recommends study update every 3 years

Standards Addressing Arc Flash HazardsElectrical Workplace Safety

Arc Flash Calculations IEEE 1584-2002 “Guide for Performing Arc

Flash Calculations” It presents formulas for numerically

quantifying heat energy from arc-flash

Includes an Excel Spreadsheet “Arc-FlashHazard Calculator” that performs calculationsusing heat energy formulas

5 5

Cost of Arc Burn Injuries

~2000 injuries/year in U.S.

An injured worker can spend one day in the hospital foreach single percent of body burned

$10,000 to $15,000,000 USD cost per injury

High personal cost

Other injuries besides thermal burns

6 6

Electrical Injuries Cost More than Other Injuries

Although injuries are infrequent, the very high costsassociated with these injuries make them one of the mostimportant categories of injuries

In one utility, electrical injuries represented <2% of allaccidents, but 28% - 52% of injury costs

7 7

Injury Costs can Last a Lifetime

A study of one utility revealed these costs of asurvivable serious electrical injury

Immediate direct costs…… $250,000 USD Direct costs after year 1….. $1.3 million Indirect costs ……………… $11.24 million

Total ….. $12.8 million*

*1991 dollars. Equivalent in 2003 dollars is $17.4 million

8 8

What’s New in IEEE1584?IEEE 1584-2002 Guide for Performing Arc Flash Calculations

July 2017 Draft Ballot

The draft ballot was successful, over 1000 commentswere received.

A Ballot Resolution Committee was formed to addressALL comments.

After resolutions, the final draft will be recirculated to ALLballoters where each can reaffirm or change their vote.

The draft ballot was approved by 84% of the ballotters

New version of IEEE1584 should be published in 2018.

9 9

What’s New in IEEE1584?IEEE 1584-2002 Guide for Performing Arc Flash Calculations

Planned Changes and Potential Consequences

2002 testing was based on about 100 tests, since thenover 100o tests

Electrode orientation details will be included Six vertical electrode equations One horizontal electrode equation (higher) Some current thinking “we are not seeing burn

injuries sing the 2002 calculations, so is a horizontalcalculation necessary/applicable?”

125kVA and 240V minimum Deleted reference from NFPA70E several cycles

ago The likelihood of an arc event at 208V is very low

10 10

Overarching Trends

Advancing Hazard & Risk concepts Hazard = Does a hazard exist? Yes/No Risk = Likelihood and Severity

Estimate the likelihood of occurrence Estimate the potential severity

Risk Controls Hierarchy = 1) Elimination; 2) Substitution; 3) Engineering controls;

4) Awareness; 5) Administrative controls; 6) PPE

What’s New in NFPA70E-2018?NFPA70E-2018 Standard for Electrical Safety in the Workplace

Definitions

Replace the term “accident” with “incident” “accidental” is replaced with “unintentional” “accidentally” is replaced with “unintentionally”

Replace “short circuit current” with "available fault current” Definition: Fault Current, Available. The largest amount of current

capable of being delivered at a point on the system during a short-circuit condition

11 11


Definitions

Conditions of Maintenance Definition: the state of the equipment considering the manufacturer’s

instructions, recommendations , and applicable codes, standards andrecommended practices

Exceptions

Two new exceptions have been added to Equipment labelingrequirements

First exception allows retaining labels if they were installed prior tothe effective date of this standard if the labels meet the requirementscontained in the applicable 70E when labels were applied.

Second exception allows supervised Industrial installations, todocument the information required in the labels to be readily availableto persons likely to perform servicing, maintenance and operation.

12 12


PPE

Requirement that all suppliers or manufacturers of PPE shalldemonstrate conformity with the appropriate product standardswith the following information on the PPE or within manufacturer’sinstructions

Name of the manufacturer Product performance standards Arc Rating where appropriate One of more identifiers such as model, serial number Care instructions

13 13


Electrical Safety Program Equipment Verification

Electrical Safety Program includes requirement for verificationof integrity of newly installed or modified electrical equipmentto comply with applicable installation codes and standards priorto being placed in service.

MSHA/OSHA hold the user responsible OSHA 1910.399 “only approved equipment will be installed. User

responsible to certify based on testing by manufacturer.”

Example: MV Switchgear Vacuum Replacement Circuit Breakers:ANSI/IEEE Standard C37.09.05 Requirements for Conversion of Power Switchgear

14 14


Permanently Mounted Voltage Detection

Test & Verify Exception No. 1 : An adequately rated permanentlymounted test device shall be permitted to be used to verify theabsence of voltage of the conductors or circuit parts at the worklocation, provided it meets all following requirements:

It is permanently mounted and installed in accordance with themanufacturer’s instructions and tests the conductors and circuit partsat the point of work

It is listed and labeled for the purpose of verifying the absence ofvoltage

It tests each phase conductor or circuit part both phase-to-phase andphase-to-ground

The test device is verified as operating satisfactorily on any knownvoltage source before and after verifying the absence of voltage.

15 15


Human Error

Requirement that risk assessment procedure shall address thepotential for human error and its negative consequences onpeople, processes, the work environment and equipment.

Users may need to have a detailed process for performingenergized work and some method of quantifying human error.

16 16

What’s New in the 2017 NEC?NFPA70 National Electrical Code

NEC Article 240.87

Two sections of Article 240.87 address required minimum Arc EnergyReduction for low-voltage fuses and circuit breakers rated 1200A, and higher.

Hierarchy = 1) Elimination; 2) Substitution; 3) Engineering controls; 4)Awareness; 5) Administrative controls; 6) PPE

17 17

Electrical Workplace Safety Standards Summary

The intent of NFPA 70E/CSA Z462 regarding arc flash isto provide guidelines which will limit injury to the onset ofsecond degree burns (1.2 cal/cm2).

Note: The heat reaching the skin of the worker isdependent primarily upon:

Power of the arc at the arc location Distance of the worker to the arc Time duration of the arc exposure

18 18

Device Name Bus kVBus

BoltedFault kA

DeviceBolted

Fault kA

ArcingFault kA

Trip Time(s.)

Bkr.Opening

(s.)

AFBoundary

WorkingDistance

(in.)

IncidentEnergy

(cal/cm2)

HRC

50/51/N FDR-5B 2.40 13.39 13.39 12.94 1.917 0.083 988 36 30.0 #450/51/N FDR-4B 0.48 31.63 25.37 14.06 1.917 0.083 268 18 100.5 DANGERB2_802_102B 0.48 29.9 28.58 15.97 0.19 0 65 18 9.9 #3MaxTripTime @2.0s 12.47 15.65 10.8 10.47 2 0 967 36 29.4 #4EPP_1 0.208 3.74 3.74 2.18 1.934 0 75 18 12.4 #3T_M1-205 FUSE 0.48 22.68 18.84 10.35 2 0 281 24 44.8 DANGER50/51/N FDR-6B 0.48 27.5 26.79 15.16 1.917 0.083 187 18 55.9 DANGER50/51/N FDR-6B 0.48 27.5 26.79 15.16 1.917 0.083 187 18 55.9 DANGERM3_003_2A 0.48 30.47 30.47 16.98 0.32 0 97 18 18.8 #350/51/N FDR-5B 2.40 16.42 13.65 13.13 1.917 0.083 971 36 29.5 #450/51/N FDR-5B 2.40 9.96 8.13 7.89 1.917 0.083 600 36 18.5 #3M3_002_2A 0.48 20.21 19.3 11.42 0.32 0 72 18 11.7 #3M3_001_2D 0.48 27.98 23.9 13.49 0.19 0 62 18 9.2 #3M3_004_2A 0.48 25.88 22.85 12.27 0.32 0 89 24 8.2 #3T_J7_001_FUSE 0.48 17.61 17.18 10.38 2 0 212 18 68.5 DANGERT_M2_001_FUSE 4.16 12.7 11.54 11.15 0.775 0 352 36 11.0 #3T_M2_001_FUSE 4.16 12.7 11.54 11.15 0.775 0 352 36 11.0 #3T_M1-101 FUSE 4.16 11.38 11.38 11.02 1.55 0 637 36 19.6 #3T-M1-102 FUSE 4.16 11.38 11.38 11.02 1.551 0 637 36 19.6 #3T_M1-201 FUSE 0.48 44.25 35.98 17.67 0.429 0 149 24 17.7 #3T_M1-201 FUSE 0.48 44.25 35.98 15.02 1.239 0 267 24 41.5 DANGERT-M1-202 FUSE 0.48 45.79 36.23 16.18 0.723 0 157 18 41.9 DANGERT_M1-204 FUSE 0.48 46.44 35.85 15.98 0.779 0 164 18 44.8 DANGERM3_003_1B 0.48 47.76 34.53 16.75 0.5 0 164 24 20.2 #3T_M1_203_FUSE 0.48 47.76 34.53 14.23 1.976 0 358 24 64.0 DANGERM3_004_2B 0.48 18.21 18.21 10.94 0.32 0 69 18 10.8 #3T_M1_206_FUSE 0.48 23.68 18.75 10.84 2 0 224 18 74.7 DANGER50/51/N FDR-5B 0.48 28.69 26.01 14.63 1.917 0.083 267 18 100.0 DANGERMaxTripTime @2.0s 12.47 15.63 10.79 10.46 2 0 966 36 29.4 #4MaxTripTime @2.0s 12.47 15.63 10.79 10.46 2 0 966 36 29.3 #4MaxTripTime @2.0s 4.16 6.35 3.79 3.74 2 0 416 36 12.9 #3B2_802_102B 0.48 28.39 27.13 15.28 0.19 0 64 18 9.5 #3

Arc Flash Results – Areas for Concern

Typical Result From an NFPA70E Arc FlashHazard Assessment

19 19

Methods/Technologies to Reduce Arc-FlashEnergy, Protecting Personnel and Equipment

Label Equipment & Train Personnel Minimize Risk with Good Safety

Practices Reduce Available Fault Current Faster Clearing Times Move People Further Away Redirect Blast Energy Arc-Flash Preventing Technologies Design the Hazard Out (Safety by

Design)

8 cal/cm2 PPE

40 cal/cm2 PPE

20 20

Bad – Exposed Back of Neck Good – All of Body Protected

Label Equipment & Train PersonnelMinimize Risk with Good Safety Practices

21 21

Faster Clearing TimesZone Selective Interlocking

SD=0.5S

SD=0.3S

SD=0.3S

SD=0.3S

M1

F1 F2 F3X35kA fault current

Without ZSI = 0.5 S:

43.7 Cal/cm2

Greater than Cat. 4 PPE

DANGER!

With ZSI = 0.08 S:7.0 Cal/cm2

FR Shirt & PantsCat. 2 PPE

22 22

LV Power Circuit Breakers – Two Settings Groups Trip Unit Mounted Features

Blue LED “Maintenance Mode” 2 Position Selector Switch:

O/R = OFF/Remote I = LocalON

5 Position Protection Level SelectorSwitch: From L1 (Min) to L5 (Max)Instantaneous

Remote Indication Capabilities Remote Enable Capabilities ARMsTM Selector switch Mounted on

Switchgear Communications

Infra-Red via PDA Various Networks

Faster Clearing TimesARMSTM (Arc Flash Reduction Maintenance System)

23 23

HRC = 1 (< 4 cal/cm2)AF Current = 5.6kAAF Current = 5.6kA

HRC = 3 (11 cal/cm2)

ARMSTM (Arc Flash Reduction Maintenance System)


24 24

Faster Clearing TimesRetrofit ARMs for LVPCBs

Door MountedComponents

Breaker MountedComponents

Arcflash Reduction Maintenance System

DIGITRIP

Harness

LockoutSwitch

Battery

25 25

2000kVA Unit Substation

NEC Article 240.21(C)2 Allows unprotectedsecondary conductorTransformer Secondary Conductors Not over 3 m(10 ft) Long

Design Limitations• Secondary bus

fault protection• Secondary bus

overload protection

2000kVA5.75%Z

3200A


EDR4000

To Primary Bkr

26 26

Fault at 480V Switchgear Bus• 31.8kA Symmetrical Fault current• 1167” AF Boundary• 702.4 cal/cm @ 18”• UNAPPROACHABLE:

NFPA70E-2009: Category 4 ishighest category @ 40 cal/cm

Safety: Unit Substation DesignTypical LV Substation with Fused Load-Break Switch

Arc Flash Study Results

Faster Clearing TimesVCP-T Substation Vacuum Retrofill

3200A

125E

13.8kV

480Y/277V

2000kVA5.75%Z

1200A

1200A

1200A

1200A

27 27

15kV VacuumBreaker

Before AfterArc Flash Study ResultsSym. Fault at 480V Switchgear Bus 31.8kA 31.8kAAF Boundary 1167” 18”Cal/cm2 702.4 1.4NFPA70E HRC UNAPPROACHABLE 1

Improved Unit Substation DesignLV Substation with Retrofit Vacuum Primary Breaker

86

ST

Integral50/51 Relay

50/51Relay

Faster Clearing TimesVCP-T Substation Vacuum Retrofill

28 28

Optional Accessory - Electrical Levering Device

ExternalRemoteRacking

Move Personnel Further Away5 to 38kV Switchgear Remote & Integral Racking

Integral RemoteRacking

UniversalRemoteRacking

29 29

MR2 Motorized Racking Device– Integral to switchgear

Remote HMI for indication,Monitoring and Control

RemoteMarshallingPanel

Move Personnel Further AwayRemote Racking HMI or Marshalling Panel

30 30

Redirects Arc Energy and Particulates

Redirect Blast EnergyArc-Resistant Switchgear (ANSI C37.20.7)

Arc Flaps

2000A or 3000A breakerwith Vent1200A can be 1

high or 2 high

ControlSection

VT drawer

15 kV Arc Switchgear

Arc Rated ANSI/NEMA Assemblies

31 31

Traditional Infrared ThermographSurvey using IR Windows orViewports

Specific Visual Inspections

Scheduled regularly for longerintervals between ShutdownMaintenance

Arc-Flash Preventing TechnologiesIR Windows or Viewports

32 32

Safety: Non PPE Unit Substation DesignTypical LV Substation with Replacement VCP-TVacuum Breaker in MSB Assembly

Design the Hazard Out (Safety by Design)VCP-T Substation Vacuum Breaker

33 33

Design the Hazard Out (Safety by Design)VCP-T Substation Vacuum Breaker

LV Switchgear

Substation One-LineAlternate Primary Protection

ZSI

ZSIZSIZSIZSI

5051505150

515051

LVPCBL,S,I800AF800AT


(3) 100:5 CT

(3) 3200:5 CT

(3) 3150:1 CURRENT SENSORS

OCRELAY







MVVCBL,S,I600AF3150AT

34 34

Design the Hazard Out (Safety by Design)FlashGard LV Motor Control Centers

ANSI/NEMA FlashGardTM

The industry’s first (and only) LV MCC witha rackable bucket!

35 35

The FlashGardTM Bucket

Bucket Position

Connected

Test

Withdrawn

Handle Mechanism

Device Island

• Start, Stop, Auto, Man

Unit Latch

Breaker

Internal Shutter Position

Open

Closed

Racking Tool Receiver

Starter


36 36

FlashGard - Remote Racking Option DC Motor Wireless Option Attaches Easily Minimal Torque Required 25 Foot Pendant Station Interfaces With Eaton RPR-2


37 37

Case Study Chemical Processing Plant - Overview

“Implementation of an Arc Flash Reduction Maintenance Switch – A Case Study”Thomas Domitrovich, Ken White, IEEE IAS ESW-2012-08

Energized Task: Removing cables from de-energized Cubicle 4 using a rope. “Tool”changed from a rope to a come-along

US Chemical Plant – Review of an Arc Flash incidentoccurring during energized work

Come Along

38 38

Arc Flash ReductionMaintenance System

Maintenance Switch Case Study: Chemical Plant

40 ms

1000kVA transformer upstream 20,918 amps of available fault

current Energy:

17.7 Cal/cm2 : No arc reducingtechnology

2.9 Cal/cm2 : With arc reducingtechnology

PPE utilized - 8 cal/cm2 (the sitestandard PPE clothing)

Come Along

39 39

Light Sensing Relay Marketing ClaimsManufacturer 1 Manufacturer 2

Manufacturer 3

A Look at Light Detection: LV Systems

40 40

Arc Flash Incident Energy isdictated by total clearing time 1,000kVA, 480V, 5.75%Z

Transformer, IFL = 1,204A,ISC = 20,918A, IARC = 11,134A

Software Instantaneous Trip:17.7 Cal/cm2 @ 18”

Light & Current Relay Trip:15.2 Cal/cm2 @18”

Air Circuit Breaker with ArcReduction Maintenance System Trip:2.57 Cal/cm2 @ 18”

Light Detection offers only a marginal benefit versus instantaneoustrip and does not match ARMS total clearing time!

A Look at Light Detection: LV Systems

Light Detected,fires Shut Trip

BreakerContacts

Part

FaultClears

FaultClears

FaultClears

BreakerContacts

Part

Breakercontacts

part

ETUpowers

up

TA fired

4ms

4ms

25ms 16ms 13ms

2ms 35ms 13ms

16ms 13ms

Analogpowers up

SoftwareInstantaneousTrip~58ms

Light SensorTripping aCircuitBreaker~50ms

ARMS Trip~33ms

Tripping DelayTime

Opening Time ArcingTime

Opening Time ArcingTime

DelayTime

Opening TimeArcingTime

DelayTime

Using Chemical Plant Case Study as an example

41 41

Light Detection Systems – Other Considerations

Questions to Ask What is the total clearing time

improvement with lightdetection?

What clearing time valuesshould be included in the arc-flash study?

Our company PSE’s model arc flash exposure with light detectionrelays with zero total clearing time improvement versus instantaneous

Manufacturer’s Position Cannot be responsible for

enhanced level of protection Cannot be responsible for

possible nuisance operation Glass fiber breaking/ shipping

splits UL has no test standard

(UL508)

42 42

Reduces incident energy far belowmethods that rely on a breaker to

clear the fault (e.g. ARMS, ZSI, busdifferential, arc detection relays)

Reduces incident energy far belowmethods that rely on a breaker to

clear the fault (e.g. ARMS, ZSI, busdifferential, arc detection relays)

Arc Quenching System extinguishesan arc flash in less than 4 ms

Arc Quenching System extinguishesan arc flash in less than 4 ms

Dramatically ReducedDowntime

Switchgear can be quicklyreturned to service after anarc flash event for minimal

downtime

Dramatically ReducedDowntime

Switchgear can be quicklyreturned to service after anarc flash event for minimal

downtime

Superior Personnel ProtectionMeets IEEE C37.20.7, Type

2B test guide for internalarcing faults

Superior Personnel ProtectionMeets IEEE C37.20.7, Type

2B test guide for internalarcing faults

Enhanced EquipmentProtection

Protects valuable switchgearassets from arc flash damage

Enhanced EquipmentProtection

Protects valuable switchgearassets from arc flash damage

No plenums, ducts, specialconstruction or venting into the

room

No plenums, ducts, specialconstruction or venting into the

room

“Always-on” system that requires nooperator activation

“Always-on” system that requires nooperator activation

Higher impedance than bolted faultsystems to reduce stress on

upstream equipment

Higher impedance than bolted faultsystems to reduce stress on

upstream equipment

Design the Hazard Out (Safety by Design)Arc Quenching Low Voltage Switchgear

43 43

Arc Quenching System Sequence of Operation1. Arc flash detected by light sensors and

CTs2. Eaton Arc Flash Relay verifies light is from

an arc event and not from normal ACBoperation

3. Arc Flash Relay sends two signals:1) Trigger Arc Quenching Device2) Trip Main Breaker

4. Arc Quenching Device quenches thearc and contains the arc energy

5. Main LV breaker (or upstream MV breaker)opens, de-energizing the lineup

<4ms

Up to50ms

44 44

Arc Quenching Device Specifications 85 kA @ 635 V 30 cycle withstand rating Modbus communications Withdrawable Same size as MDS breaker Through-the-door design Remote racking capability Field-testable Field-replaceable System self-supervision Customer interface on front of device System includes Eaton Arc Flash

Relay (EAFR) and light sensors

45 45

Returning Gear to Service After an Event1. Arc detection relay indicates zone where event

occurred; interlocks main breaker to preventreclosing into the fault

2. Personnel locate and remove the cause of theevent

3. Evaluate and clean the equipment4. Replace Arc Quenching Device – cannot be

serviced or repaireda. Equipment can be reenergized without the Arc Quenching Device

b. Without the Arc Quenching Device, the arc flash protection will be limited tothe Arc Flash Relay and Main Breaker operation

5. Personnel return equipment to normal operatingconditions and reenergize

Equipment downtime is greatly reduced by the ArcQuenching Device as no structures, breakers or bus

will need to be replaced

Relay

MainBreaker

ArcQuenching

Device

46 46

Metal Enclosed Switchgear AlternativesStandard

SwitchgearArc ResistantSwitchgear

Arc QuenchingSwitchgear

Protection IndustryStandard

People(passive)

People,Equipment,

Uptime(active)

Test Guides,Standards C37.20.1 C37.20.1

C37.20.7

C37.20.1C37.20.7UL 2748

The Arc Quenching System can be shipped in any type of new Magnum DS gearincluding standard NEMA 1, NEMA 3R and Arc Resistant construction to create

Arc Quenching Switchgear.

Available Now!Retrofit and MCC Arc Quenching solutions are under development!

© 2017 Eaton Corporation. All rights reserved.

Electrical Systems: Design - Install - Maintain

David B. DurocherGlobal Industry Director

Mining & MetalsEaton Corporation

Wilsonville OR [email protected]

November 2017

Arc Flash: What's New in Codes,Standards and Solutions

Documents

Arc Flash: What's New in Codes, Standards and Solutions Papers/1117_arc_flash_new_standards_eaton.pdfIEEE 1584-2002 Guide for Performing Arc Flash Calculations July 2017 Draft Ballot