8/10/2019 BruceBator Presentation C3AE

1/20

ProtectingElectricalEquipment

inHazardousLocations

Overviewoffundamentalsinregardstovariousstandards

Presentedby: BruceBator

EngineeringManager

PhoenixMecano Inc.

8/10/2019 BruceBator Presentation C3AE

2/20

KeyObjectives Providehistoricaloverviewofhazardouslocations

ProvideExfundamentalsinregardstoignitionprevention

Explanation

of

Zone

classifications

/relationship

to

Division

DiscussprotectionmethodologiesinvariousZones

8/10/2019 BruceBator Presentation C3AE

3/20

AHistoricalPerspective

1815:TheDavyLampwasintroduced.

Reasonablyrecognizedasfirsthazardous

locationapparatus.

8/10/2019 BruceBator Presentation C3AE

4/20

8/10/2019 BruceBator Presentation C3AE

5/20

MiningIndustryFlammablegases(methane)

Flammabledust(coaldust)

OilandGasIndustryFlammablegases&liquids

ChemicalIndustyFlammablegases,liquids&solids

EnergyProduction

Flammablegases&oils

Coaldust

PaintingIndustryFlammableliquids&powders

FoodstuffIndustryCombustabledusts(Flour,Sugar)

AgricultureBiogases

DisposalIndustryFlammablegases,liquids&solids

Recycling

IndustryFlammablegases,liquids&solids

MetalProcessingWelding,cutoff&grinding

processes

8/10/2019 BruceBator Presentation C3AE

6/20

In

order

for

combustion

to

occur,

all

three

(3)

legs

must

be

present,eliminateanyleg,andtheexplosioncannothappen

8/10/2019 BruceBator Presentation C3AE

7/20

Inhazardouslocations,thegoalistopreventignitionbyproviding

protectionmethodsthat

Preventexplosiveatmosphere

Avoidignition

Limittheeffectsofanexplosiontoanacceptablelevel

8/10/2019 BruceBator Presentation C3AE

8/20

PrimaryMeasure

Preventanexplosiveatmosphere

Methods

Ventilationsystems

Gasdetectionsystems

Additionofinertmaterialstodevices

Preventintroductionofcombustiblematerials

8/10/2019 BruceBator Presentation C3AE

9/20

SecondaryMeasure

Avoidignition

Methods

Employingprotective

measures

against

ignition

Classifyingmaterials,areas,anddevices

Definingacceptabletemperatures

8/10/2019 BruceBator Presentation C3AE

10/20

Ignition

Sources

Hotsurfaces

Electricalarcsandsparks

Electrostaticdischarge

Atmosphericdischarge

Mechanicalsparks

Chemicalreaction

Openflame

Electromagneticradiation

Opticalradiation

8/10/2019 BruceBator Presentation C3AE

11/20

ClassifyingMaterials

GasesandVapors(ClassI)flashpoint

ignitiontemperature

maximumsafegap

temperatureclass

DustandParticles(ClassII)smolderingtemperature

ignitiontemperature

minimumignitiontemperature

8/10/2019 BruceBator Presentation C3AE

12/20

ClassifyingAreas

Group

I

Devicesforminingindustrywheremightbe

minegasorcombustible

dust

Subdivisionin

following

categories

M1 M2

Group

II

Devicesforallotherareaswheremightbe

hazardousatmosphere

SubdivisionintoGasandDustareas

Gas(G) Dust(D)

Subdivisioninto categories

1 2 3

8/10/2019 BruceBator Presentation C3AE

13/20

Gas(G)andDust(D)aremaintainedasseparateareas

Eachareahas3categoriesthataredesignatedzones

Zonesdescribetheamountanddurationofmaterialpresent

Zone0,20:(Category1)Combustibleconcentrationsare

presentcontinuously

or

for

long

periods

under

normal

operatingconditions

Zone1,21:(Category2)Combustibleconcentrationsare

likelytobepresentundernormaloperatingconditions

Zone2,22:(Category3)Combustibleconcentrationsarenot

likelyto

exist

under

normal

operating

conditions

8/10/2019 BruceBator Presentation C3AE

14/20

DifferencebetweenNEC500&NEC505

Division1 Division2

1(Zone0,20)

2(Zone1,21)

3(Zone2,22)

Division1:Combustibleconcentrationscanexistsomeorallofthetimeundernormaloperatingconditions

Division2:Combustibleconcentrationnotlikelytoexistundernormaloperatingconditions

8/10/2019 BruceBator Presentation C3AE

15/20

ClassifyingDevicesEach

electrical

device

which

is

to

be

used

within

an

Ex

area

has

to

be

Ex

approved.

Each

device

is

approvedforuseinacategory. Thelowerthecategorynumber,themoreareasthedevicecanbe

usedin. ThecategoryinformationdefineswhichExzonesthisspecificdeviceisallowedtobe

used.

category approval can be used in zone

3G 22G 1, 2

1G 0, 1, 2

3D 22

2D 21, 22

1D 20, 21, 22

8/10/2019 BruceBator Presentation C3AE

16/20

DefiningTemperature

Themaximumtemperatureofanelectricdevicemustalways

belowerthantheignitiontemperatureofthegas.

Accordingtheirignitiontemperature,gasesaretobedivided

intotemperature

classes

(T1

to

T6).

Conversely,electricaldevicesareselectedaccordingtheir

maximumworkingtemperature,andareplacedintothe

appropriatetemperatureclass.

8/10/2019 BruceBator Presentation C3AE

17/20

TemperatureClassifications

TClass Max SurfaceTemp Ignitiontempofmaterial

T1 450C >450C

T2 300C >300C

T3 200C >200C

T4 135C >135C

T5 100C >100C

T6 85C

>

85C

Tm

Ta To

To Surfacetemperature

Tm Internalheatingtemperature

Ta

Ambienttemperature

8/10/2019 BruceBator Presentation C3AE

18/20

ComparisonofAcceptableProtectionMethodsClassIDivision1 ClassIZone0

IntrinsicSafety Intrinsic

Safety

"ia"

Explosionproof Encapsulation"ma"

Purge/Pressurized(TypeXorY)

ClassIZone1

Flameproof"d"

Intrinsicsafety"ib"

Encapsulated"mb"

PowderFilling"q"

OilImmersion

"o"

IncreasedSafety"e"

Pressurization"px"or"py"

Class1Division2 ClassIZone2

HermeticallySealed Encapsulated"mc"

Nonincendive Intrinsicsafety"mc"

Nonsparking Pressurization"pz"

Purge/Pressurized(TypeZ) EnergyLimited"nL/nC"

Nonsparking

"nA"

Restrictedbreathing"nR"

8/10/2019 BruceBator Presentation C3AE

19/20

KeyTake

Aways

TheuseofClassZoneinUSAbringscloseralignmentto

internationalcommunity

TheuseofClassZoneallowspossibleprotectionmethodsnot

allowedunder

Class

Division

Youstillmustuseanapprovedprotectionmethodforthearea

youareplacingthedevice

8/10/2019 BruceBator Presentation C3AE

20/20

1