Application Guide AG300 Issue 15 - BEKA€¦ · Description of ATEX & IECEx dust certification 5.1...

Application GuideAG300 Issue 15

BA300G & E Seriesintrinsically safe 4/20mAloop powered indicators

http://www.beka.co.uk/

Contents

1. Introduction

2. Description

3. Intrinsicsafetycertifications

3.1 IECExcertification

3.2 ATEXcertification

3.3 USandCanadiancertification

4. Description of ATEX & IECEx gas certification

4.1 Certificationlabel

4.2 Zones, gas groups and T rating

4.3 4/20mA input

4.4 Optionaldisplaybacklighting

4.4.1 Loop powering

4.4.2 Separately powering

4.5 Optional alarms

5. Description of ATEX & IECEx dust certification

5.1 Certificationlabel

5.2 Zones, dust groups and surface temperature

6. Description of North American certification

6.1 FMcertificationofBA304Eand BA324E

6.2 FMcertificationofBA307E,BA308E, BA327EandBA328E

6.3 ETLandcETLcertificationof BA304G & BA324G

7. Hazardous areas applications

7.1 4/20mAloopdesign

7.2 Remoteindication

7.3 Displaybacklight

7.3.1 Looppoweringthe backlight

7.3.2 Separatelypoweringthe backlight

7.4 OptionalAlarms

8. Special functions

8.1 Squarerootextractor

8.2 Lineariser

8.3 Tare

9. Rugged panel indicator application

9.1 BA307E-SSandBA327E-SS

9.1.1 Installation in an Ex e panel enclosure

9.1.2 Installation in an Ex p panel enclosure

9.1.3 Expxbpanelenclosure

9.1.4 Ex pzc panel enclosure

9.1.5 Expybpanelenclosure

9.1.6 Ex t panel enclosure

9.1.7 InstallationintheUSA and Canada

9.2 BA304G-SS-PM&BA324G-SS-PM

9.2.1 Installation in an Ex e panel enclosure

9.2.2 Installation in an Ex p panel enclosure

9.2.3 Expybenclosure

9.2.4 Expxbenclosure

9.2.5 Ex pzc enclosure

9.3 Installation in an Ex t panel enclosure

1. INTRODUCTIONThe first BA300 series intrinsically safe loop powered4/20mA indicator was introduced in 1984, since then therangehasbeencontinuouslydeveloped through theB,Cand D models. This edition of Application Guide AG300describestheuseofthefourthgenerationintrinsicallysafeE&Ginstrumentsincludingtheruggedstainlesssteelpanelmountingmodelsintroducedin2014andextendedin2018.

For applications in Zone 2 hazardous areaswithout theneed for an intrinsically safe interface such as a Zenerbarrierorgalvanicisolator,ExnAcertifiedfieldandpanelmounting models are available. SeeApplication GuideAG310 for details.

TheBA500seriesduplicatesthecompleterangeoffieldand panel mounting models for safe area applications.

2. DESCRIPTIONTheBA300G&Eseriesindicatorsarelooppoweredbythe4/20mAcurrenttheyaremeasuringanddonotrequireanadditionalpowersupply.Allthemodelscanbecalibratedtodisplay the4/20mA inputcurrent inengineeringunits,theymaybeusedinnewinstallationsandarebackwardscompatible allowing them to replace earlier B, C andDsuffixmodels.

Fig1showsasimplifiedblockdiagramofaBA300seriesindicator.The4/20mAinputcurrentflowsthroughresistorR1andforwardbiaseddiodeD1.ThevoltagedevelopedacrossD1,which is relativelyconstant, ismultipliedandused topower theanalogue todigital converterand theliquid crystal display.The voltage developed acrossR1,whichisproportionaltothe4/20mAinputcurrent,providestheinputsignalfortheanaloguetodigitalconverter.Thistechnique allows all models to drop less than 1.2V inthe4/20mAloop,andenables the two input terminals tocomplywiththerequirementsforsimple apparatus.

Less than1.2V

4/20mAinput

2

3

4

R1

D1

8

9

10

11

1

12

13

Powersupply

alarm 1

alarm 2

Optionalbacklight

Optionalalarms

Analogueto digitalconverter

++

+

14

Common

Loop powered -

-Separatelypowered

Field mountingmodels only

5

6

Fig1SimplifiedblockdiagramofaBA300GorEintrinsicallysafe indicator.

ThefeaturesofalltheintrinsicallysafeBA300G&Emodels aresummarisedinTables1and2.Detailedspecificationsfor each model are contained in individual datasheetsavailablefromBEKAassociatessalesdepartmentortheymaybedownloadedfromtheBEKAwebsiteatwww.beka.co.uk/datasheets.html.

3. INTRINSIC SAFETY CERTIFICATIONSThe BA300G & E series indicators have internationalintrinsicsafetycertificationsallowingthemtobeinstalledingasanddusthazardousareasworldwide.

3.1 IECExcertificationAllmodelshaveanIECExCertificateofConformityissuedbyCertificationBodyIntertekTestingandCertificationLtd.IECExcertificates,whicharebasedon international IECstandards,arealreadyacceptabledirectlyor indirectly inlargepartsoftheworld.

3.2 ATEXcertificationNotified Body Intertek Testing and Certification Ltd hasissued all models with an EU or EC-Type ExaminationCertificateconfirmingcompliancewithharmonisedBSENstandardswhichhavebeenused to confirmcompliancewith the European Explosive Atmospheres Directive2014/34/EU.TheinstrumentscarrytheCommunityMarkand,subject to localcodesofpractice,maybe installedin any of the European EconomicArea (EEA) membercountries. ATEX certificates are also acceptable inSwitzerland, Iceland, Liechtenstein, Norway andTurkey.TheEuropeanCommission’sBlueGuideliststhememberstates, overseas countries and territories that haveadoptedharmonisationlegislation.

BritishBSENstandardsarebasedon international IECstandards,thereforeATEXandIECExcertificatesnowusesimilarterminologyandfortheseindicatorsareidentical.

ThisguidedescribesATEXandIECExinstallationswhichconformwithIEC/BSEN60079-14Electrical installations design, selection and erection.WhendesigningsystemsforinstallationoutsidetheUK,thelocalCodeofPracticeshouldalwaysbeconsulted.

3.3 USandCanadiancertificationAllmodelsexcepttheBA304G-SS-PM&BA324G-SS-PMhave certification allowing installation in the USA andCanada which have been issued by two NationallyRecognised Testing Laboratories NRTLs, FM and ETL.FortheUSAboththetraditionalNEC500ClassandDivisionclassification,whichisacceptableforinstallationonmostNorthAmericansites,andthemorerecentNEC505Zoneclassification are included. US NEC505 intrinsic safeequipment is codedAEx and the approval is similar tointernationalIECExandEuropeanATEXcertifications.

CanadiancertificationalsoincludesbothDivisionandZoneclassifications. TheCanadianElectricalCodemandatesthatnewinstallationsuseZones,butClassandDivisionsarestillfrequentlyemployed.

3

http://www.beka.co.uk/datasheets.html

4

FieldGRP

141 x 212mm

Enclosurematerial & size

Model BA304E BA324E

Shown with optionalbacklight

Protection

Separate terminal compartment Yes

Number of digits 4 5and 31

segmentbargraph

Height of digits 34mm 29mm

Certification International & EuropeEx ia IIC T5 Ga -40°C Ta +70°CIECEx gas

Options Optional items must be specified when indicator is ordered

BacklightAlarmsExternal keypad

Certification IECEx & ATEX dust US and Canadian

Ex ia IIIC T80°C Da IP66 -40°C Ta +70°C dust

II 1G, Ex ia IIC T5 Ga -40°C Ta +70°CATEX gas

II 1D, Ex ia IIIC T80°C Da IP66 -40°C Ta +70°C dust

Additional certificationfeatures


AvailableAvailable

Available

AvailableAvailable

AvailableAvailable

Available

AvailableAvailable

Table 1 BA300G & E intrinsically safe indicators

BA304G

No

4

34mm

IP66

AvailableStandard

Available

StandardStandard

FieldGRP

122 x 120mm

FieldStainless steel 316122 x 120mm

BA304G-SS

4

34mm

Certification USA & Canada Class I Division 1 Groups A, B, C & D T5Class II Division 1 Groups E, F & G T5Class III T5Class I Zone 0 AEx ia IIC T5-40ºC Ta +70ºC

Class I, Div 1, Gp A, B, C & D T5Class I, Zone 0, AEx ia IIC T5 Ga (USA only)-40ºC Ta 70ºC

Class II, Div 1, Gp E, F & G. Class III, Div 1Zone 20 AEx ia IIIC T80ºC Da (USA only)-40ºC Ta 60ºC

Ex ia T5 Ga -40ºC Ta 70ºC ] Ex ia IIIC Da -40ºC Ta 60ºC (Canada only)

AvailableStandard

Available

StandardStandard

5

Ex ia IIC T5 Ga -40°C Ta +70°C

Ex ia IIIC T80°C Da IP20 -40°C Ta +70°C

II 1G, Ex ia IIC T5 Ga -40°C Ta +70°C

II 1D, Ex ia IIIC T80°C Da IP20 -40°C Ta +70°C

4 5and 31

segmentbargraph

34mm 29mm

AvailableStandard

Available

StandardStandard

AvailableStandard

Available

StandardStandard

PanelPPO (Noryl)96 x 48mm


BA327E BA328E

No

5and 31

segmentbargraph

5and 31

segmentbargraph

29mm 11mm

AvailableStandard

Available

StandardStandard

AvailableStandard

Available

StandardStandard


BA307E

Front IP66 rear IP20

5and 31

segmentbargraph

4

29mm

AvailableStandard

Available

StandardStandard

IP66

BA324G

FieldGRP

122 x 120mm

FieldStainless steel 316122 x 120mm

BA324G-SS

Class I Division 1 Groups A, B, C & D T5Class I Zone 0 AEx ia IIC T5

-40ºC Ta +70ºC

BA308E

Class I, Div 1, Gp A, B, C & D T5Class I, Zone 0, AEx ia IIC T5 Ga (USA only)-40ºC Ta 70ºC

Class II, Div 1, Gp E, F & G. Class III, Div 1Zone 20 AEx ia IIIC T80ºC Da (USA only)-40ºC Ta 60ºC

Ex ia T5 Ga -40ºC Ta 70ºC ] Ex ia IIIC Da -40ºC Ta 60ºC (Canada only)


15mm

AvailableStandard

Available

StandardStandard

6

Enclosurematerial & size

Model

Shown with optionalbacklight

Protection

Separate terminal compartment

Number of digits

Height of digits

Certification International & EuropeEx ia IIC T5 Ga -40°C Ta +70°CIECEx gas

Options Optional items must be specified when indicator is ordered

BacklightAlarmsExternal keypad

Certification IECEx & ATEX dust US and Canadian

Ex ia IIIC T80°C Da IP66 -40°C Ta +70°C dust

II 1G, Ex ia IIC T5 Ga -40°C Ta +70°CATEX gas

II 1D, Ex ia IIIC T80°C Da IP66 -40°C Ta +70°C dust



Table 2 Rugged panel mounting indicators

BA304G-SS-PM

4

34mm

AvailableStandard

Available

StandardN/A

PanelStainless steel 316

122 x 120mm

BA324G-SS-PM

5and 31

segmentbargraph

29mm

Certification USA & Canada Class I Division 1 Groups A, B, C & D T5Class II Division 1 Groups E, F & G T5Class III T5Class I Zone 0 AEx ia IIC T5-40ºC Ta +70ºC

AvailableStandard

Available

StandardN/A

AvailableStandard

Available

StandardStandard

AvailableStandard

Available

StandardStandard

Certification permits installation inAEx e, AEx p or AEx t panelenclosure without invalidating

enclosure’s certification.

Certification permits installation inEx e, Ex p or Ex t panel enclosure

without invalidating the panelenclosure’s certification.

PanelStainless steel 316

105 x 60mm

BA307E-SS BA327E-SS

Front impact resistant & IP66rear IP20

No

4 5and 31

segmentbargraph

15mm 11mm

4. DESCRIPTION OF ATEX & IECEX GAS CERTIFICATION.AlloftheBA300G&EseriesindicatorsandaccessorieshaveATEXandIECExcertification.Thissectiondescribescertificationforinstallationinagashazardousarea,section5describesdustcertification.

4.1 CertificationlabelAllBA300G&EseriesindicatorsarefittedwithanexternallabelshowingtheATEXandIECExcertificationinformationand numbers. The gas certification information on aBA304EcertificationlabelishighlightedinFig2.

BA304E 4 Digit Indicator

associatesYear of manufacture shown within terminal compartment

0359

Hitchin England www.beka.co.uk

ITS11ATEX27253X IECEx ITS11.0014X

II 1 G, Ex ia IIC T5 Ga, -40°C Ta +70°C

Intrinsically safe suitable for Zone 0, 1 or 2Type of explosive atmosphere Gas

CategoryEquipment group

Explosion protection markNotified body identification (Intertek Testing & Certification)

CE Conformity mark

Gas groupTemperature class

Equipment Protection LevelCertification temperature range

Fig2BA304Egascertificationlabel

4.2 Zones, gas groups and T ratingAlloftheBA300G&Eseriesindicatorshavethefollowinggascertificationcode:

IECEx Ex ia IIC T5 Ga -40ºC≤Ta≤70ºC ATEX Group II Category 1G, Ex ia IIC T5 Ga -40ºC≤Ta≤70ºC

Whenconnectedtoasuitablesystemtheindicatormaybeinstalledin:

Zone0 explosivegasairmixturecontinuously present.

Zone1 explosivegasairmixturelikelytooccur in normal operation.

Zone 2 explosivegasairmixturenotlikelytooccur, and if it does will onlyexistforashorttime.

Beusedwithgasesingroups:

Group A propane GroupB ethylene GroupC hydrogen

Ingasesthatmaysafelybeusedwithequipmenthavingatemperatureclassificationof:

T1 450ºC T2 300ºC T3 200ºC T4 135ºC T5 100ºC

Atanambienttemperaturebetween

-40ºCand+70ºC

ThisallowstheBA300G&Eseriesindicatorstobeinstalled inallZonesandtobeusedwithmostcommonindustrialgases at an ambient temperature between -40ºC and+70ºC. Known exceptions (listed in IEC 60079-20-1)beingcarbondisulphideandethylnitratewhichhaveanignitiontemperatureof95ºC.

Note 1: BA300G & E intrinsically safe field mountingindicators inGRPenclosuresmaybefittedwitha label containing aluminium and are thereforesubject to the following conditions for safe useindicatedbyan‘X’suffixontheATEXandIECExcertificationnumbers.

When installed in a Zone 0 potentially explosive atmosphere requiring Equipment Protection Level Ga apparatus, the instrument shall be installed such that even in the event of rare incidents, an ignition source due to impact or friction between the aluminium label and iron/steel is avoided.

These special conditions for safe use of fieldmountingBA304GandBA324GGRPindicatorsare not restrictive as it is very unlikely that anindicator would be installed in Zone 0 wherea potentially explosive atmosphere is alwayspresent.TherequirementdoesnotapplywhenaGRPindicatorisinstalledinZone1or2.

The requirement does not apply toBA304G-SS, BA324G-SS, BA304G-SS-PL andBA324G-SS-PMindicatorswhichhavestainlesssteelenclosuresandlabels.

7

4.3 4/20mA inputSourcesofenergy thatdonotgeneratemore than1.5V,100mA and 25mW are, for intrinsic safety purposes, considered to be simple apparatus (Clause 5.7 of IEC60079:11).Simple apparatus is easier to incorporate into intrinsicallysafesystemsandrequireslessdocumentationthanothercertifiedintrinsicallysafeapparatus.

Although the BA300G & E series indicators do notthemselves comply with the requirements for simple apparatus, the ATEX and IECEx certificates specifythat under fault conditions the voltage, current andpower output (Uo; Io; Po) from the 4/20mA inputterminals will not exceed those specified for simple apparatus. This allows the output safety parameters ofthe indicator to be ignoredwhen calculating the intrinsicsafety of a loop into which an indicator is inserted.

Itisonlynecessarytoestablishthattheoutputparametersoftheloopareequaltoorlessthantheinputparametersof the indicator and that the internal inductance andcapacitanceoftheindicatorareacceptable.

Theoutputparametersoftheloopwhicharedeterminedbytheintrinsicallysafeinterfacepoweringtheloop,beitaZenerbarrier,galvanicisolatororassociatedapparatusshouldbeequaltoorlessthan:

Uo ≤ 30Vdc Io ≤ 200mA Po ≤ 0.84W

The maximum equivalent capacitance and inductancebetween the two 4/20mA input terminals 1 and 3 of anindicatorare:

BA300E BA300G Ci = 13nF 5.4nF Li = 0.02mH 0.02mH

Todeterminethemaximumpermissiblecableparametersof the loop, these figures, plus Ci and Li for any otherinstruments in the loop, should be subtracted from thespecifiedCoandLofortheZenerbarrier,galvanicisolatororassociatedapparatuspoweringtheloop.

Apparatus certificates for intrinsically safe interfacesusually specifyCoandLo for IICgases (hydrogen), thefigures for IIB (ethylene) and IIA (propane) gases areconsiderablylarger.

Itisunlikelythattheadditionalinductanceoftheindicatorwill be restrictive and can usually be ignored, but theadditionalindicatorcapacitancewillreducethemaximumpermissiblecablelength.

4.4 OptionaldisplaybacklightingAll BA300G & E series indicators can be supplied withan optional factory fitted green backlight that has threeterminalsallowingittobelooporseparatelypowered.

When looppowered, thebacklightproducesbackgroundillumination allowing the indicator display to be read atnightandinpoorlightingconditions.Looppoweringdoesnot require an additional power supply, intrinsically safeinterfaceorfieldwiring,butthemaximumvoltagedropinthe4/20mAloopcausedbytheindicatorisincreasedfrom1.2 to5.0V. Backlightbrilliance isconstantbetween6and20mAbutslightlydiminishesbelow6mA.

When separately powered, the backlight produces abrighterbackgroundilluminationwhichenhancesdaylightviewingoftheindicatordisplay,butanadditionalintrinsicallysafeinterfaceandfieldwiringarerequired.Themaximumvoltagedropoftheindicatorinthe4/20mAloopremainsat1.2V.

4.4.1 Loop poweringTo power the display backlight from the 4/20mA loop,backlight terminals12&13areconnected inserieswiththe 4/20mA indicator input terminals as shown in Fig 6

Both the ATEX and IECEx certificates confirm thatterminals3&12complywiththerequirementsofsimple apparatuswhenthe indicator’s4/20mAinput terminals1&3areconnected inserieswith thebacklight, terminals12 & 13. The input intrinsic safety parameters of thecombined indicator and loop powered backlight are thesameasthosefortheindicatoralone.Theindicatorandloop powered backlight may therefore be connected inserieswithanycertifiedintrinsicallysafecircuitprovidingtheoutputparametersofthecircuitdonotexceed:

Uo ≤ 30Vdc Io ≤ 200mA Po ≤ 0.84W

The maximum equivalent capacitance and inductancebetweeninputterminals3and12are:


Todeterminethemaximumpermissiblecableparametersof the loop, these figures, plus Ci and Li of any otherinstrument in the loop, should be subtracted from thespecifiedCoandLofortheZenerbarrier,galvanicisolatororassociatedapparatuspoweringtheloop.

The loop powered backlight increases the maximumvoltagedropoftheBA300G&Eseriesindicatorsto5V.

8

4.4.2 Separately poweringThebacklightissegregatedfromallothercircuitswithintheindicatorandhasbeencertifiedasaseparateintrinsicallysafecircuit.Itispoweredviaterminals12and14whichmaybeconnected toany intrinsicallysafepowersupplysuchasacertifiedZenerbarrierorgalvanicisolatorhavingoutputparametersequaltoorlessthan:

Uo ≤ 30Vdc Io ≤ 200mA Po ≤ 0.84W

TheATEXandIECExcertificatesspecifythatthemaximumequivalent capacitance and inductance between thebacklightterminalsis:


TodeterminethemaximumpermissiblecableparametersthesefiguresshouldbesubtractedfromthespecifiedCoandLofortheZenerbarrierorgalvanicisolatorpoweringthebacklight.

4.5 Optional alarmsAllindicatorscanbesuppliedwithtwofactoryfittedsinglepolesolidstatealarmoutputs.Eachoutputisgalvanicallyisolatedandhasbeencertifiedasaseparateintrinsicallysafe circuit which, complies with the requirements forsimple apparatus.

This allowseachalarmoutput to switchany intrinsicallysafecircuitwithoutputparametersnotexceeding:

Uo ≤ 30Vdc Io ≤ 200mA Po ≤ 0.84W

TheATEXandIECExcertificatesspecifythatthemaximumequivalent capacitance and inductance between theterminalsofeachalarmoutputis:

BA300E BA300G Ci = 24nF 0 Li = 0.01mH 0.01mH

Todeterminethemaximumpermissiblecableparametersthese figures, plus Ci and Li for other apparatus in thecircuit, should be subtracted from the specified Co andLo of the Zener barrier, galvanic isolator or associatedapparatuspoweringthecircuit.

9

5. DESCRIPTION OF ATEX & IECEX DUST CERTIFICATIONAllBA300G&EintrinsicallysafeindicatorscanbesuppliedwithATEXandIECExdustcertification.BA300GfieldandtheBA300Epanelmountingmodelshavedustcertificationasstandard,butitmustberequestedforBA300Eseriesfieldmountingmodels.

5.1 CertificationlabelAllBA300G&EseriesindicatorsarefittedwithanexternallabelshowingtheATEXandIECExcertificationinformationand numbers. The dust certification information on aBA304EcertificationlabelishighlightedinFig3.

BA304E 4 Digit Indicator

associatesYear of manufacture shown within terminal compartment

0359

Hitchin England www.beka.co.uk

II 1 G, Ex ia IIC T5 Ga, -40°C Ta +70°C

II 1 D, Ex ia IIIC T80°C Da IP66, -40°C Ta +70°C

ITS11ATEX27253X IECEx ITS11.0014X

Explosion protection mark

Notified body identification (Intertek Testing & Certification)

CE Conformity mark

Equipment group

Category

Type of explosive atmosphere Dust

Intrinsically safe

Dust group

Max surface temperature

Equipment Protection Level

Ingress protection

Certification temp. range

Fig3BA304Edustcertificationlabel

5.2 Zones, dust groups and surface temperatureAlloftheBA300G&Eseriesindicatorshavethefollowingdustcode:

Group IICategory1DEx ia IIICT80ºCDa IP66 -40ºC≤Ta≤70ºC

Whenconnectedtoasuitablesystemtheindicatorsmaybeinstalledin:

Zone20 explosiveatmosphereintheform ofacloudofcombustibledustin air is continuously present, or for longperiodsorfrequently.

Zone21 explosiveatmosphereintheform ofacloudofcombustibledustin airislikelytooccuroccasionally in normal operation.

Zone22 explosiveatmosphereintheform ofacloudofcombustibledustin airisnotlikelytooccurinnormal operation,butifitdoesoccur,will onlypersistforashortperiod.

Beusedwithdustinsubdivisions:

IIIA combustibleflyings IIIB non-conductivedust IIIC conductivedust.See note

HavingaMinimumIgnitionTemperatureof:

Dustcloud 120°C

Dustlayeronindicator 155°C upto5mmthick

Dustlayeronindicator Referto over5mmthick. IEC60079-14

Atanambienttemperaturebetween-40and+70°C.

Note: BA300E series panel mounting indicators haveIP20rearprotectionandaresubjecttothefollowingspecialconditionsforsafeuseindicatedbyan‘X’suffixontheATEXandIECExcertificationnumbers.

‘When installed in a IIIC conductive dust atmosphere, the indicator shall be mounted such that the instrument terminals have at least IP6X protection.’

ThesespecialconditionsdonotaffectinstallationsinIIIA,IIIBdustorgasatmospheres.

IP6Xindicatesthattherearofthepanelmountingindicatorshouldbetotallyprotectedfromdust,byfor example mounting the indicator in a sealedIP6Xpanelenclosureorcubiclesothatconductivedustcannotaccumulateontheindicatorterminals.For96x48mmandruggedindicators,thiscanbeachievedwithaBA495rearcoversealingkit.

10

Beusedwithdustsingroups:

Group E Metal GroupF Carbonaceous GroupG Non-carbonaceous

Atanambienttemperaturebetween-40ºCand+70ºC

Note: AEx ia IIC T5 Zone coding allows installation in atmospheres similar to those specified for IECEx andATEXcertificationinsection4.

6.2 FMcertificationofBA307E,BA308E,BA327E &BA328EThe BA307E, BA308E, BA327E and the BA328E panelmounting indicators have the following FM and cFMintrinsicsafetycodes:

ClassI Division1 GroupsA,B,C&DT5 Class I Zone 0 AEx ia IIC T5 -40ºC≤Ta≤+70ºC

When connected to a suitable system these panelmountingindicatorsmaybeinstalledin:

Division1 Explosivegasairmixturelikelyto occur in normal operation

Division2 Explosivegasairmixturenotlikelyto occur and if it does will only exist for a shorttime.


Group A Acetylene Group B Hydrogen GroupC Ethylene GroupD Propane

Ingassesthatmaysafelybeusedwithequipmenthavingatemperatureclassificationof:



Note: AEx ia IIC T5 Zone coding allows installation in atmospheres similar to those specified for IECEx andATEXcertificationinsection4.

FM & cFM certification of the rugged BA307E-SS &BA327E-SSisdescribedinsection9.1.7

6. DESCRIPTION OF NORTH AMERICAN CERTIFICATIONBEKA loop powered indicators have been certifiedintrinsically safe foruse in theUSAandCanadaby twoNationally Recognised Testing Laboratories, FM GlobalandETL.Class/DivisionandZoneapprovalisincludedfor all models.

AllinstallationsintheUSAshouldcomplywiththeassociatedBEKA Control Drawing Installation of Intrinsically Safe Systems for Hazardous (Classified) Locations ANSI/ISA RP12.6 and theNational Electrical Code ANSI/NFPA70. AnylocalcodeofPracticeshouldalsobeconsulted.

InstallationsinCanadashouldcomplywiththeassociatedBEKA Control Drawing, the Canadian Electrical CodeC22.1,plusanyrelevantlocalcodeofpractice.

6.1 FMcertificationofBA304E&BA324EThe BA304E and the BA324E field mounting indicatorsincorporatingaseparate terminalcompartmenthave thefollowingFMandcFMintrinsicsafetycodes:

ClassI Division1 GroupsA,B,C&DT5 ClassII Division1 GroupsE,F&GT5 Class III T5 Class I Zone 0 AEx ia IIC T5 -40ºC≤Ta≤+70ºC

Whenconnected toasuitablesystem the BA304EandBA324Efieldmountingindicatorsmaybeinstalledin:





Ingasesthatmaysafelybeusedwithequipmenthavingatemperatureclassificationof:


11

6.3 ETLandcETLcertificationofBA304G&BA324GTheBA304Gand theBA324G fieldmounting indicatorshavethefollowingETLandcETLintrinsicsafetycode:

ClassI Div1 GpA,B,C,DT5(USA&Canada) Class I Zone 0 AEx ia IIC T5 Ga (USA) -40ºC≤Ta≤70ºC

ClassII Div1 Gp E, F, G Class III, Div 1 (USA & Canada) Class II Zone 20 ExiaIIICT80ºCDa(USA) -40ºC≤Ta≤60ºC

ExiaT5Ga -40ºC≤Ta≤70ºC] ExiaIIICDa -40ºC≤Ta≤60ºC (Canada)

Whenconnected toasuitablesystemthe BA304GandBA324Gfieldmountingindicatorsmaybeinstalledin:





Ingassesthatmaysafelybeusedwithequipmenthavingatemperatureclassificationof:



Beusedindustsingroups:

Group E Metal GroupF Carbonaceous GroupG Non-carbonaceous


Note: AEx ia IIC T5 Ga andAEx ia IIIC T80ºC Zonecodingsallowinstallationinatmospheressimilartothosespecified for IECEx andATEX certification in sections 4and 5.

12

7. HAZARDOUS AREAS APPLICATIONSBA300G and E series ATEX, IECEx, US and Canadian certificationsspecifycommonindicatorsafetyparameters.The circuits shown in this sectionmay be usedwith allindicatorsandwithanyoftheintrinsicsafetycertificationsprovidingthattheinstallationcomplieswiththelocalcodeof practice.

ThefourruggedstainlesssteelpanelmountingindicatorshavethesameIECExandATEXgasanddustcertificationas the other models, although only the BA307E-SS &BA327E-SS have US certification. Whilst they maybe used in any of the examples shown in this section,theircertificationalsopermits themtobemounted inanapertureinacertifiedExe,ExporExtpanelenclosurewithout invalidating the panel enclosure’s certificationwhich further extends their applications. The use oftheseruggedinstrumentsincertifiedpanelenclosuresisexplainedinsection9ofthisguide.

7.1 4/20mA loop designA BA300G or E series indicator may be connected inseries with almost any intrinsically safe 4/20mA currentloop and calibrated to display themeasured variable orcontrolsignalinengineeringunits.Therearefourdesignsteps:

1. From tables 1 or 2 select the model with therequireddisplay,mountingandaccessories.

4 digit models can display -9999to9999

5 digit models can display -99999to99999withabargraph

2. The output safety parameters of the 4/20mAloop, which are usually defined by the Zenerbarrier,galvanic isolatororassociatedapparatuspoweringtheloop,mustbeequaltoorlessthanthe maximum input safety parameters of theindicator,whichare:

Uo ≤ 30Vdc Io ≤ 200mA Po ≤ 0.84W

3. TheequivalentinternalcapacitanceCiandinternalinductanceLioftheindicatorwithorwithoutalooppoweredbacklightis:


WhenaddedtotheCiandLiofotherinstrumentsin the loop, the totals should not exceed thespecifiedCoandLooftheZenerbarrier,galvanicisolator or associated apparatus powering theloop.

4. The loop must be able to supply the additional1.2V required to operate the indicator. If theoptionalbacklight is looppoweredthe loopmustbeabletosupplyanadditional5V.

ABA300GorEseriesindicatormaybeconnectedinserieswith a 2-wire intrinsically safe transmitter to display thecurrentandhencetheprocessvariableinengineeringunits.Fig4Aillustratestheuseofa2-channelZenerbarrier,ortwoseparatebarriersastheintrinsicallysafeinterface.Zenerbarriersareusually lessexpensivethangalvanic isolatorsbutdonotprovideisolationandrequireahighintegrityearthwhichifnotavailablemaybeexpensivetoinstall.

TAG NUMBER SCALE

2-wireTx

2 channel Zener barrier28V; 93mA; 300Ωdiode return

4/20mA

4/20mA

4/20mA Load250Ω

Instrumentpowersupply

+

0

3 4 2 16 5

Safe AreaHazardous Area

BA300G or E indicator

Fig4ATransmitterlooppoweredviaZenerbarriers

ConsideringthevoltagedroparoundtheloopinFig4A.

2-wiretransmitter 8.0V

Maximumvoltagedropcaused 1.2V byBA300GorEseriesindicator.

Maxvoltagedropcausedby 6.8V 28V93mAbarrier. (340Ωend-to-endresistancex20mA)

Maxvoltagedropcausedby 1.4V diodereturnbarrier (21Ωx20mA+0.9V)

Maxvoltagedropcausedby 5.0V 250Ωload.(250Ωx20mA)

Maxvoltagedropcausedby 0.2V cables.(10Ωx20mA) ______ Totalvoltagedroparoundloop 22.6V

The instrument power supply must therefore have anoutputabove22.6Vbutbelow25.5Vwhichisthemaximumworkingvoltageofthe28V93mAZenerbarrier.

Fig4Billustratesthesameloopusingagalvanicisolatorastheintrinsicallysafeinterface.Galvanicisolatorsalthoughmoreexpensive thanZenerbarriersallowanon-floatingpowersupply tobeused,donot requireahigh integrityearth connection and in general are easier to apply. Itis usually only necessary to read the manufacturersspecification todetermine thevoltageavailable topowerthehazardousarealoop.

13

TAG NUMBER SCALE

2-wireTx

4/20mA4/20mA

3 4 2 16 5 28V; 93mAgalvanic isolator

4/20mA

PowerSupply

+

0



Fig4BTransmitterlooppoweredviagalvanicisolator

7.2 Remote indicationBA300G&Eseries indicatorsmayalsobedrivenviaanintrinsically safe interface from a 4/20mA safe area signal to providearemoteindicationwithinahazardousarea.Thetypeof interface isnot critical, aZenerbarrier, galvanicisolatororassociatedapparatusmaybeused,butagainoutput parameters of the interface must not exceed theindicator’smaximuminputparameters.Zenerbarriersaretheleastexpensiveinterfaceparticularlyifahighintegrityearthisalreadyavailable.Ifonesideofthe4/20mAcurrentloop may be earthed, a single channel Zener barrierprovidesthelowestcostprotection.Ifthe4/20mAsignalisnotisolated,twoZenerbarriers,atwochannelZenerbarrieroragalvanicisolatormustbeused.Againitisnecessarytoensurethatthevoltagecapabilityofthe4/20mAsignalis sufficient to drive the indicator plus the voltage dropintroducedby the intrinsicallysafe interface.Fig5showsthethreealternativecircuitswhichmaybeused.

7.3 DisplaybacklightAll BA300G & E series indicators can be supplied withanoptional factoryfitteddisplaybacklight thathas threeterminalsallowingittobelooporseparatelypowered.

7.3.1LooppoweringthebacklightWhen loop powered, the backlight produces greenbackground illumination enabling the indicator displaytobereadatnightandinpoorlightingconditions.Looppowering does not require an additional power supply,intrinsicallysafeinterfaceorfieldwiring,butthemaximumindicatorvoltagedropinthe4/20mAloopisincreasedfrom1.2to5.0V.Backlightbrillianceisconstantbetween6and20mAbutslightlydiminishesbelow6mA.

Theindicatorsbacklightterminals12(+)and13(-)shouldbeconnected inserieswith the indicator’s4/20mA inputterminalsasshowninFig6.

Anyofthecircuitsshowninsections7.1and7.2maybeusedprovidingthat5Visavailabletopowertheindicatorandthebacklight.


Instrumentwith non-isolated4/20mAoutput

Two channelZener barrier

4/20mA

3 1

4/20mA

Instrumentwith

isolated4/20mAoutput

Single channelZener barrier

4/20mA

3 1

Instrumentwith non-isolated4/20mAoutput

Galvanicisolator

4/20mA

3 1

4/20mA

4/20mA

+

0

+

0

+

0




TAG NUMBER SCALE

EP

TAG NUMBER SCALE

EP

TAG NUMBER SCALE

EP

Fig5Alternativecircuitsforremoteindicationina hazardousareas

14

Belowtheminimumsupplyvoltagethebacklightcontinuestofunctionbutthebrillianceisdiminished.Forapplicationswhere operator’s night vision has to be preserved,adjustingthebacklightsupplyvoltageisasimplemethodofdimmingthedisplaybacklight.

Thebacklight is segregated fromallothercircuitswithintheindicatorandisseparatelypoweredviaterminals12(+)and14(-)whichmaybeconnectedtoanyintrinsicallysafeinterfacesuchasacertifiedZenerbarrier,galvanicisolatororassociatedapparatushavingoutputparametersequaltoorlessthan:

Uo ≤ 30Vdc Io ≤ 200mA Po ≤ 0.84W

The maximum equivalent capacitance and inductancebetweenthebacklightterminalsis:


To determine the maximum permissible backlight cableparameters these figures should be subtracted from thespecifiedCoandLooftheZenerbarrier,galvanicisolatoror associated apparatus powering the backlight. Fig 7showsanexampleofaZenerbarrierseparatelypoweringthebacklight.

TAG NUMBER SCALE

EP

4/20mAindicatorcircuit

Zener barriers orgalvanic isolators

14 12 3 1

Backlightsupply

+24V

0

+

04/20mA

See table 3for current

1.2VSeetable 3for minvoltage



Fig7BA300GorEseriesindicatorwithseparately poweredbacklight

Two separately powered BA307E or BA327E indicatorbacklights may be connected in parallel to a singlechannel28V,93mAZenerbarrierorgalvanicisolatorwithnonoticeablereductioninbrillianceona24Vdcsupply.

TAG NUMBER SCALE

TAG NUMBER SCALE

EP

4/20mA

Zener barrier orgalvanic isolator

4/20mA

3 1 13 12

5V+

0

5V


2-wireTx

4/20mA4/20mA

3 12 13 15 6

28V; 93mAgalvanic isolator

4/20mA

PowerSupply

+

0



Fig6AlternativecircuitsforBA300GorEseriesindicator withlooppoweredbacklight

7.3.2SeparatelypoweringthebacklightSeparatelypoweringthebacklightproducesbrightergreenbackgroundilluminationthanlooppowering.Itenhancesdaylightviewingoftheindicatordisplaybutanadditionalintrinsicallysafeinterfaceandfieldwiringarerequired,themaximumvoltagedropoftheindicatorinthe4/20mAloopremainsat1.2V.

Theseparatelypoweredbacklightisacurrentsinkdrawinga constant current when the supply between terminals12(+)and14(-)isabovetheminimumsupplyvoltage.

Model CurrentMinimum supply

voltageterminals 12 & 14

BA304E BA304G BA304G-SS BA304G-SS-PM BA324E BA324G BA324G-SS BA324G-SS-PM BA308E BA328E

35mA 11V

BA307E BA327E BA307E-SS BA327E-SS

23mA 9V

Table3Separatelypoweredbacklightvoltage&current foreachmodel

15

7.4 Optional AlarmsAll BA300G or E series indicators can be suppliedwithtwo factory fitted single pole solid state alarm outputs.Eachoutputisgalvanicallyisolatedandhasbeencertifiedasaseparate intrinsicallysafecircuitcomplyingwith therequirementsforsimple apparatusmakingiteasiertousein intrinsically safe circuits.

Eachoutputmaybe individuallyconfiguredasahighora low alarm with a normally open or a normally closed‘contact’. Fig 8 illustrates the conditions available andshowswhichare‘failsafe’.i.e.outputisinalarmcondition(‘contact’open)whenthe4/20mAinputcurrentiszero.

Normally closed output 'nc'in the non-alarm condition

FAIL SAFE

Normally open output 'no'in the non-alarm condition

NOT FAIL SAFE

4/20mA Input 4/20mA Input

4/20mA Input4/20mA Input

AlarmSetpoint

AlarmSetpoint

AlarmSetpoint

AlarmSetpoint

HIGHALARM

LOWALARM

Outputclosed

Outputclosed

Outputclosed

Outputclosed

OutputOpen

OutputOpen

OutputOpen

OutputOpen

Fig8Alarmoutputs

These alarm outputs are not suitable for use in criticalsafetyapplicationssuchasashutdownsystem.

The equivalent electrical circuit of each alarm output isshown inFig9.Bothoutputsarepolarisedandwillonlypass current in one direction.

(8, 10)

(9, 11)

(8, 10)

(9, 11)

5Ω 0.7V

1M 24nF BA300E 0 BA300G

0.01mH +

==

Fig9Equivalentcircuitofeachalarmoutput

Each alarm output is segregated and is a separateintrinsicallysafecircuit.Itmayswitchanyintrinsicallysafecircuitwithoutputparametersequaltoorlessthan:

Uo ≤ 30Vdc Io ≤ 200mA Po ≤ 0.84W

The maximum equivalent capacitance and inductancebetweentheterminalsofeachalarmoutputis:

BA300E BA300G Ci = 24nF 0 Li = 0.01mH 0.01mH

To determine the maximum permitted circuit cableparameters,theseCiandLiparameters,plusthoseofanyotherdeviceinthecircuit,shouldbesubtractedfromtheCoandLoofthecertifiedZenerbarrier,galvanicisolatororassociatedapparatuspoweringthealarmcircuit.

Thealarmoutputsmaybeusedtoswitchintrinsicallysafeloadswithinthehazardousareaortoswitchsafearea loads viaaZenerbarrieroragalvanicisolator.Fig10 illustrates how one alarm output of a BA300 series indicator canswitchacertifiedintrinsicallysafesolenoidvalvelocatedinthehazardousareaandtheotheralarmoutputcancontrola pump in the safe area via a switch transfer galvanicisolator.

TAG NUMBER SCALE

2-wireTx

4/20mA

Alarm 1

4/20mA

24V supply

4/20mA

3 4 2 1

4/20mAsupply

10 11 8

+ +

9

Solenoiddriver

Switchtransfer

Alarm 2

CertifiedGalvanic isolators

Pump

+0

0+

0+



Intrinsically safesolenoid valve

Fig 10 Typical alarm application

When an indicator alarm output is used to activate anannunciatorsuchasaflashingbeaconorasounderoneoftheindicatorpushbuttonsmaybeconfiguredtooperateasanalarm‘accept’button.Thisallowstheoperatortosilencethealarmforaconfigurabletimeupto3,600secondsin1secondincrements.Ifthealarmconditionisnotcorrectedduringthesilencetime,thealarmwillbereactivated.

16

8. SPECIAL FUNCTIONSAll BA300G & E series indicators include special functions thatextendtheirapplications.

8.1 Square root extractorAll the BA300G & E series indicators contain a squareroot extractor that allows the output from non-lineariseddifferentialflowtransmitterstobedisplayedinlinearunits.Therootextractorisselectablefromwithintheindicator’sconfigurationmenuusingtheinstrument’spushbuttons.


TAG NUMBER SCALE

levelTx

4/20mA

4/20mAoutput

4/20mA

Horizontal cylindrical tank

3 4 2 1

4/20mAsupply

+0

4 8 12

Input current

Indi

cato

r di

spla

yTa

nk c

onte

nt in

vol

umet

ric u

nits

16 20

161514

13

12

11

10

9

8

7

6

5

43

21


Fig11 Lineariserenablestankcontentstobedisplayed inlinearunitsofvolume

8.2 LineariserTheintegrallineariserenablesBA300G&Eseriesindicatorstodisplaynon-linearvariablesinlinearengineeringunits.The function provides a sixteen point fully adjustablestraight line lineariserwhichmay be conditioned on-sitetocompensate formostnon-linearities.Fig11showsanexample inwhich aBA300 series indicator displays thecontentsofahorizontalcylindricaltankinlinearvolumetricunits fromthe4/20mAoutputofa level transmitter. Theinternalindicatorlineariserconvertsthetanklevel4/20mAsignal intoa lineardisplayof thevolumebeingstored inthetank.

Thelinearisercanbeadjustedon-siteviatheinstrumentspush buttons, or if the curve parameters are specifiedwhentheindicatorisordered,itcanbesuppliedcalibrated.

8.3 TarePrimarilyintendedforusewithweighingsystems,thetarefunctionreplacesthepercentagefunctionontheindicator.Whenthetarepushbuttonisoperatedformorethanthreeseconds the indicatordisplay isset tozeroand the tareannunciatoractivated,thussubtractingthecurrentdisplayfrom subsequent displays. When used with a weighingsystem, this function subtracts the displayed weight ofanemptycontainerfromtheweightofthecontainerpluscontents,sothatthenetweightofthecontentsisdisplayed.Subsequentoperationofthetarepushbuttonforlessthan3secondswillreturntheindicatortothegrossdisplayanddeactivatethetareannunciator.

17

9. RUGGED PANEL INDICATOR APPLICATIONSThese rugged panel mounting indicators have the sameIECExandATEXcertificationastheothermodelsandmaybeusedinanyoftheapplicationsshowninsection7ofthisguide.TheyhaveimpactandIP66ingressresistantfrontpanelsandareidealforuseinharshenvironmentsorwherethefrontoftheinstrumentislikelytobeimpacted.

Inadditiontheseruggedindicatorsmaybeinstalledintoanaperture inacertifiedExe,ExporEx tpanelenclosurelocatedinZone1,2,21or22withoutinvalidatingthepanelenclosure’scertification.Thisenablesaruggedindicatorto display a process variable in a hazardous area panelproviding protection for equipment such as Ex e motorcontrols for a compressor.

Thesmall rugged indicatorsBA307E-SSandBA327E-SSand the larger BA304G-SS-PM and BA324G-SS-PMhave different certifications and installation requirements.Thereforeeachtypeisdescribedseparately.

9.1 BA307E-SSandBA327E-SSBothinstrumentsarehousedinruggedcast316stainlesssteel caseswith a 10mm thick toughened glasswindow.The joint between the instrument case and the panelenclosure inwhich it ismounted is sealedwitha captivesilicone gasket. After high and low temperature thermalendurance ageing, followed by impact testing at low andhigh temperatures, notified body Intertek Testing andCertificationissuedthestainlesssteelcasewithcomponentcertificates IECEx ITS14.0007U and ITS14ATEX17967UconfirmingthatthefrontofthecaseprovidesIP66ingressprotectionandcomplieswithExe,ExpandExtimpactandingressrequirements.TheseATEXandIECExcomponentcertificatessupplementtheExiaintrinsicsafetycertificatesITS14ATEX28077X and IECEx ITS14.0048X for theBA307E-SS and BA327E-SS indicators which specifyspecialconditions forsafeusewhen installed inanExe,Ex p or Ex t panel enclosure.

9.1.1 Installation in an Ex e panel enclosureInstallation of a BA307E-SS or BA327E-SS indicator inanExeIICGbincreasedsafetypanelenclosuredoesnotinvalidate the Ex e panel’s certification, but the indicatorremains Group II Category 1G Ex ia IIC T5 Ga intrinsically safeapparatus, therefore itmustbepoweredviaaZenerbarrierorgalvanicisolatorasdescribedinsection7ofthisguide.

The Zener barrier or galvanic isolator is usually installedin thesafeareabutsome intrinsicallysafe interfacesarecertifiedformountingwithinaprotectiveenclosurelocatedinZone2whichmaypermitthemtobemountedinthesameExeenclosureastheruggedindicator.WheretheZenerbarrierorgalvanicisolatormaybelocatedisdefinedbyitsATEXEU-TypeExaminationcertificateorIECExCertificateofConformity.Zenerbarriersandgalvanicisolatorsarenotpermitted in Ex e enclosures located in Zone 1.

For personnel safety and prevention of an electrostaticcharge,ruggedindicatorsshouldbeelectricallyconnectedtothepanelenclosureinwhichtheyaremounted,ortoalocalbondingpointifthepanelenclosureisnon-conductive.Theindicatorterminals,thewiringtotheindicatorandtheintrinsicallysafeinterface,ifmountedwithintheenclosure,should be segregated fromall other non-intrinsically safewiringandequipmentwithinthepanelenclosure.

Required segregation distances are defined in standardsEN60079-11Equipment protected by intrinsic safety and EN60079-14Electrical installations design, selection and erection. Terminals for intrinsically safe circuits shouldbe segregated by at least 50mm from terminals for non-intrinsicallysafecircuitsandfrombareelectricalconductors.

The intrinsically safe terminals and wiring should beidentified and, if live maintenance is to be performed,any bare live non-intrinsically safe parts within the panelenclosureshouldbecoveredandlabelled‘Non-intrinsicallysafecircuit’topreventaccidentalcontact.

Zenerbarrier

4/20mA

Ex e cableglands

BA307E-SS or

BA327E-SSindicator

+4/20mAindicatorcircuit

Zone 1 or 2 hazardous area

Safe area

Ex e panel

enclosure

BA3X7E-SS

Fig 12 Typical installation in an Ex e panel enclosure

18

Fig12showsaBA307E-SSorBA327E-SSruggedindicatorinstalled in an Ex e panel enclosure located in Zone 1 or 2. The 4/20mA cable should be sealedwith anEx ecertifiedglandwhereitenterstheExepanelenclosureandthecablescreenshouldbeearthedtoacommonpoint inthesafeareasuchas theplant’sequipotentialconductor,ortotheZenerbarrierbusbarwhenbarriersareused.Toprevent fault currents from other equipment installed intheExeenclosureflowingtoearthviathiscablescreen,itshouldbeinsulatedinthehazardousareaandshouldnotbeconnectedtotheExeenclosure.

Thepowerdissipationwithinanindicatorfittedwithalarmsand a backlight which is separately powered is normallyabout 350mW, in the very unlikely event that all fourcircuits fail to theworst caseconditionat the same time,thetotalpowerdissipationrisesto3.4Wwhichcouldraisetheinternaltemperatureofasmallthermallywellinsulatedpanel enclosure.

9.1.2 Installation in an Ex p panel enclosureInstallationofaBA307E-SSorBA327E-SSruggedindicatorin anEx p panel enclosure does not invalidate theEx ppanelenclosure’singressorimpactprotectionasthefrontoftheruggedindicatorscomplywiththeExpingressandimpactrequirements.

Because the BA307E-SS and BA327E-SS front panelpushbuttoncontactsareoutsideofthepressurisedpanelenclosure, these two indicators remainGroup IICategory1G Ex ia IIC T5 Ga intrinsically safe apparatus and may onlybeconnectedtoanappropriateintrinsicallysafecircuit,evenwhenmountedinanExpxborExpzcpanelenclosurewhich reduce theequipmentprotection level (EPL) insidetheenclosurefromGb(Zone1)tonon-hazardous.

Bothindicatorshavefourrearpanelventstoensurethatapotentiallyexplosivegasisnottrappedwithintheinstrumentcase,wheninstalledinanExppanelenclosurethesevents,whichareshowninFig13,shouldnotbeobstructed.

Do not obstruct 4 rear vents wheninstalled in an Ex p enclosure

Fig13PositionofventsinBA307E-SS&BA327E-SS

For personnel safety and prevention of an electrostaticcharge, BA307E-SS & BA327E-SS rugged indicatorsshould be electrically connected to the panel enclosureinwhich the indicator ismounted, or to a local bondingpoint if the panel enclosure is non-conductive. Theindicator terminals, the wiring to the indicator and theintrinsicallysafeinterface,ifmountedwithintheenclosure,should be segregated from all other non-intrinsicallysafe wiring and equipment within the panel enclosure.RequiredsegregationdistancesaredefinedinstandardsEN60079-11Equipment protected by intrinsic safety and EN 60079-14 Electrical installations design, selection and erection. Terminals for intrinsically safe circuits should be segregated by at least 50mm from terminalsfor non-intrinsically safe circuits and frombareelectricalconductors.

Safe areaZone 1 or 2 hazardous area

4/20mA3 1

BA307E-SS orBA327E-SS indicator

Protectivegas inlet

Ex p panelenclosure

Gland maintainsenclosure integrity

2 channel Zener barrier28V; 93mA; 300Ωdiode return

Load

Instrumentpowersupply

+

0

Scalecard

BA3X7E-SS

P E

Fig 14 Typical installation in Ex p panel enclosure

BA307E-SS and BA327E-SS rugged indicators may beinstalledinallthreetypesofpressurisedpanelenclosure,Ex pxb, Ex pyb and Ex pzc as shown in Fig 14. The4/20mAcableshouldbesealedbyaglandwhichmaintainsenclosureintegritywhereitenterstheExpenclosureandthecablescreenshouldbeearthedinthesafeareatoacommonpointsuchastheplant’sequipotentialconductor,ortotheZenerbarrierbusbarwhenbarriersareused.

To prevent fault currents from other equipment installedwithin theExpenclosure flowing toearth via this cablescreen,itshouldbeinsulatedinthehazardousareaandshouldnotbeconnectedtotheExpenclosure.

19

20

TheZenerbarrier,galvanicisolatororassociatedapparatusisusuallyinstalledinthesafearea.Alternatively,asuitablycertifiedintrinsicallysafeinterfacesuchasaZenerbarrier,galvanicisolatororassociatedapparatusmaybemountedwithintheExtenclosure.Wherethecertifiedintrinsicallysafeinterfacemaybeinstalledisdefinedbyit’sEU-TypeExaminationCertificateorIECExCertificateofConformity.

The4/20mAcableshouldbesealedbyaglandwhere itenters the Ex t enclosure and the cable screen shouldbeearthed in thesafearea toacommonpoint suchastheplantsequipotentialconductor,ortotheZenerbarrierbusbarwhenbarriersareused.Topreventfaultcurrentsfromotherequipment installedwithin theEx tenclosureflowing toearthvia thiscablescreen, thescreenshouldbe insulated in the hazardous area and should not beconnectedtotheExtenclosure.

Bothindicatorshaveanearthstudadjacenttotheterminalson the rearpanel. Forpersonnel safetyandpreventionof an electrostatic charge this should be electricallyconnectedtothepanelenclosureinwhichtheindicatorismounted,ortoalocalbondingpointifthepanelenclosureisnon-conductive.

Theindicatorterminals,thewiringtotheindicatorandtheintrinsicallysafeinterface,ifmountedwithintheenclosure,should be segregated from all other non-intrinsicallysafe wiring and equipment within the panel enclosure.Requiredsegregationdistancesaredefined instandardsIEC60079-11Equipment protected by intrinsic safety and IEC60079-14Electrical installations design, selection and erection. Terminals for intrinsically safe circuits shouldbesegregatedbyat least50mm from terminals fornon-intrinsicallysafecircuitsandfrombareelectricalconductors.

The intrinsically safe terminals and wiring should beidentified and if live maintenance is to be performedanybare livenon-intrinsicallysafepartswithin thepanelenclosureshouldbecoveredandlabelled‘Non-intrinsicallysafecircuit’topreventaccidentalcontact.

The power dissipation within an indicator fitted withoperational alarms and a backlight which is separatelypowered is normally about 350mW, in the very unlikelyeventthatallfourcircuitsfailtotheworstcaseconditionatthesametime,thetotalpowerdissipationrisesto3.4Wwhich could raise the internal temperature of a smallthermallywellinsulatedpanelenclosure.

9.1.3ExpxbpanelenclosureWhen pressurised an Ex pxb enclosure reduces theequipment protection level (EPL) inside the enclosurefromGb (Zone1) to non-hazardous. When theExpxbpanel enclosure is located in Zone 1, a BA307E-SS orBA327E-SS rugged indicator installed in the enclosuremayonlybeconnected toanEx iaorEx ib intrinsicallysafe circuit which will usually have it’s intrinsically safeinterfacelocatedinthesafearea.Alternatively,asuitablycertifiedintrinsicallysafeinterfacesuchasaZenerbarrier,galvanicisolatororassociatedapparatusmaybemountedwithin the Ex pxb enclosurewith the indicator. Wherethecertifiedintrinsicallysafeinterfacemaybeinstalledisdefinedbyit’sEU-TypeExaminationCertificateorIECExCertificateofConformity.

9.1.4 Ex pzc panel enclosureWhen pressurised an Ex pzc enclosure reduces theequipment protection level (EPL) inside the enclosurefromGc (Zone 2) to non-hazardous. When theEx pzcpanel enclosure is located in Zone 2 a BA307E-SS orBA327E-SSruggedindicatorinstalledintheenclosuremayonlybeconnectedtoanExia,ExiborExicintrinsicallysafe circuit which will usually have it’s intrinsically safeinterfacelocatedinthesafearea.Alternatively,asuitablycertifiedintrinsicallysafeinterfacesuchasaZenerbarrier,galvanicisolatororassociatedapparatusmaybemountedwithin the Ex pzc enclosure with the indicator. Wherethecertifiedintrinsicallysafeinterfacemaybeinstalledisdefinedbyit’sEU-TypeExaminationCertificateorIECExCertificateofConformity.

9.1.5ExpybpanelenclosureWhen pressurised an Ex pyb enclosure reduces theequipment protection level (EPL) inside the enclosurefrom Gb (Zone 1) to Gc (Zone 2). When the Ex pybpanel enclosure is located in Zone 1 a BA307E-SS orBA327E-SS rugged indicator installed in the enclosuremayonlybeconnectedtoanExiaorExibintrinsicallysafecircuitwhichwillusuallyhaveit’sintrinsicallysafeinterfacelocatedinthesafearea.Alternatively,asuitablycertifiedintrinsicallysafeinterfacesuchasaZenerbarrier,galvanicisolatororassociatedapparatusmaybemountedwithinthe Ex pyb enclosure. Where the certified intrinsicallysafeinterfacemaybeinstalledisdefinedbyit’sEU-TypeExaminationCertificateorIECExCertificateofConformity.

9.1.6 Ex t panel enclosureInstallation of a BA307E-SS or BA327E-SS ruggedindicator in a certified Ex t (dust ignition protection byenclosure) panel enclosure does not invalidate theEx t panel’s impact and ingress protection as the frontof both indicators comply with Ex t impact and ingressrequirements. However, because the indicator’s frontpanelpushbuttoncontactsareoutsideof theenclosurethe rugged BA307E-SS or BA327E-SS may only beconnected to an appropriate intrinsically safe circuit, Ex ia oribforZone21installationsandExia,iboricforZone22installations.Anyofthecircuitsshowninsection7ofthisApplicationGuidemaybeused.

21

9.2 BA304G-SS-PMandBA324G-SS-PMThese rugged 4 and 5 digit indicators are similar tothe rugged BA307E-SS and BA327E-SS, but havelarger displays. They have a cast 316 stainless steelfront panel with a toughened glass window, the jointbetween the instrument case and the panel enclosurein which the indicator is mounted is sealed with asiliconegasket.Afterhighandlowtemperaturethermalenduranceageingfollowedbyimpacttestingatbelowtheminimumandabove themaximumservice temperature,notified body Certification Management Ltd issuedcomponent certificates 18ATEX3128U and 29U andIECExCML18.0071U confirming that the front of theenclosureprovidesIP66ingressprotectionandcomplieswithExe,ExpandExtimpactandingressrequirements.These ATEX and IECEx component certificatessupplement theEx ia intrinsic safety certificates for theindicatorsITS11ATEX27253XandIECExITS11.0014X.

9.2.1 Installation in an Ex e panel enclosureInstallation of a BA304G-SS-PM or BA324G-SS-PMindicatorinanExeIICGbincreasedsafetypanelenclosuredoesnot invalidate theExepanel’scertification,but theindicator remains Group II Category 1G Ex ia IIC T5 Ga intrinsicallysafeapparatus,thereforeitmustbepoweredvia a Zener barrier or galvanic isolator as described insection7ofthisguide.

TheZenerbarrier or galvanic isolator is usually installedin thesafeareabutsomeintrinsicallysafe interfacesarecertifiedformountingwithinaprotectiveenclosurelocatedinZone2whichmaypermitthemtobemountedinthesameExeenclosureastheruggedindicator.WheretheZenerbarrierofgalvanicisolatormaybelocatedisdefinedbyitsATEXEU-TypeExaminationcertificateorIECExCertificateofConformity. Zenerbarriersandgalvanic isolatorsarenot permitted in Ex e enclosures located in Zone 1.

For personnel safety and prevention of an electrostaticcharge,ruggedindicatorsshouldbeelectricallyconnectedto the panel enclosure in which they are mounted, orto a local bonding point if the panel enclosure is non-conductive. The indicator terminals, the wiring to theindicator and the intrinsically safe interface, if mountedwithintheenclosure,shouldbesegregatedfromallothernon-intrinsically safe wiring and equipment within thepanel enclosure. Required segregation distances aredefined in standards EN 60079-11Equipment protected by intrinsic safetyandEN60079-14Electrical installations design, selection and erection. Terminals for intrinsically safecircuitsshouldbesegregatedbyatleast50mmfromterminals fornon-intrinsicallysafecircuitsand frombareelectrical conductors.

The intrinsically safe terminals and wiring should beidentified and if live maintenance is to be performedanybare livenon-intrinsicallysafepartswithin thepanelenclosureshouldbecoveredandlabelled‘Non-intrinsicallysafecircuit’topreventaccidentalcontact.

9.1.7 Installation in the USA and CanadaTheBA307E-SSandBA327E-SSruggedindicatorshavethe following FM and cFM intrinsic safety certificationpermitting installation inbothDivisionsandZones in theUSA and Canada.

ClassI Division1 GroupsA,B,C&DT5 Class I Zone 0 AEx ia IIC T5

-40ºC=Ta=+70ºC

Whenconnectedtoasuitablesystemtheseruggedpanelmountingindicatorsmaybeinstalledin:

Division1 Explosivegasairmixturelikelyto occur in normal operation.

Division2 Explosivegasairmixturenot likelytooccur,andifitdoeswill onlyexistforashorttime.

Beusedwithgasesingroups: Group A Acetylene Group B Hydrogen GroupC Ethylene GroupD Propane

Ingasesthatmaysafelybeusedwithequipmenthavingatemperatureclassificationof: T1 450°C T2 300°C T3 200°C T4 135°C T5 100°C

Atanambienttemperaturebetween-40°Cand+70°C.

For installations of these rugged indicators in the USAand Canada the intrinsically safe circuits shown in thisApplication Guide may be used providing the Zenerbarriers and galvanic isolators have local approval andthe installationcomplieswith theBEKAControlDrawingCI300-72. Acopyof thisControlDrawing is included intheBA307E-SSandBA327E-SSinstructionmanualwhichmaybedownloadedfromtheBEKAwebsite.

Section 14 of the FM and cFM intrinsic safety ControlDrawing CI300-72 states that when correctly installedinanAExe,AExn,AExporAExtpanelenclosure,therugged BA307E-SS andBA327E-SS indicatorswill notinvalidatetheenclosurecertification.

InstallationrecommendationsfortheseruggedindicatorsinExe,ExpandEx tenclosuresdescribed insections9.1.1 to 9.1.6 of this guidemay therefore also be usedfor similar installations in the US and Canada, but theinstallationmustcomplywiththelocalcodeofpractice.

Note:CertifiedAExe,AExn,AExpandAExtenclosuresmayonly be installed in areaswith zoned classification,notinareaswithdivisionclassification.

22

The power dissipation within an indicator fitted withoperational alarms and a backlight which is separatelypowered is normally about 350mW, in the very unlikelyeventthatallfourcircuitsfailtotheworstcaseconditionatthesametime,thetotalpowerdissipationrisesto3.4Wwhich could raise the internal temperature of a smallthermallywellinsulatedpanelenclosure.

For personnel safety and to prevent the accumulationofanelectrostaticcharge, thestainlesssteel frontpanelshouldbeelectricallyconnectedtothepanelenclosureinwhichtheindicatorismountedbyfittingaringtagunderoneofthefourrearofpanelfixingscrews.

9.2.2 Installation in an Ex p panel enclosureInstallationofaruggedBA304G-SS-PMorBA324G-SS-PMindicator inanExppanelenclosuredoesnot invalidatethe Ex p panel enclosure’s ingress or impact protectionasthefrontoftheruggedindicatorscomplywiththeExpingressandimpactrequirements.

Unlike the smaller BA307E-SS and BA327E-SS ruggedindicators, the front panel push button contacts of theBA304G-SS-PM and BA324G-SS-PM are within therugged indicator, and hence inside of the pressurisedpanelenclosure.Therefore,wheninstalledinaExpxborExpyzpressurisedenclosurewhichreducestheequipmentprotectionlevelEPLinsidetheenclosuretonon-hazardous,aruggedBA304G-SS-PMorBA324G-SS-PMindicatordoesnotrequireprotectionbyaZenerbarrier,galvanic isolatororintrinsicallysafeoutputfromassociatedapparatus.TheinstallationshouldcomplywithrequirementsofIEC60079-2Equipment protection by pressurised enclosure.


Installation of a BA304G-SS-PM or BA324G-SS-PMrugged indicator in an Ex e panel enclosure located in Zone1or2isshowninFig15.The4/20mAcableshouldbesealedwithanExecertifiedglandwhereitenterstheEx e panel enclosure and the cable screen should beearthedtoacommonpoint in thesafeareasuchas theplant’s equipotential conductor, or to the Zener barrierbusbarwhenbarriersareused.Topreventfaultcurrentsfrom other equipment installed in the Ex e enclosureflowingtoearthviathiscablescreen,itshouldbeinsulatedinthehazardousareaandshouldnotbeconnectedtotheEx e enclosure.

Isolator orZener barrier

4/20mA

BA304G-SS-PMindicator

+4/20mAindicatorcircuit

Zone 1 or 2 Hazardous area

Safe area

Ex e, Ex p or Ex t

panel enclosure

Ex e cableglands

Fig 15 Typical installation in an Ex e, Ex p or Ex t panel enclosure

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15/10/2018issue15

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9.2.3ExpybenclosureWhen pressurised, an Ex pyb enclosure reduces theequipment protection level (EPL) inside the enclosurefromGb(Zone1)toGc(Zone2).WhencorrectlyinstalledinanExpybenclosure the indicatorshouldbepoweredbyanappropriatelyratedZenerbarrierorgalvanicisolatorlocated in a safe area

9.2.4ExpxbenclosureWhen pressurised, an Ex pxb enclosure reduces theequipmentprotectionlevel(EPL)insidetheenclosurefromGb(Zone1)tonon-hazardous.WhencorrectlyinstalledinanExpxbenclosuretheindicatormaythereforebeusedwithoutaZenerbarrierorgalvanicisolator.

9.2.5 Ex pzc enclosureWhen pressurised, an Ex pzc enclosure reduces theequipmentprotectionlevel(EPL)insidetheenclosurefromGc(Zone2)tonon-hazardous.WhencorrectlyinstalledinanExpzcenclosuretheindicatormaythereforebeusedwithoutaZenerbarrierorgalvanicisolator.

9.3 Installation in an Ex t panel enclosureInstallation of a BA304G-SS-PM or a BA324G-SS-PMruggedindicatorinacertifiedExt(dustignitionprotectionby enclosure) panel enclosure does not invalidate theEx t panel’s impact and ingress protection as the frontof both indicators comply with Ex t impact and ingressrequirements.

Unlike the BA307E-SS and BA327E-SS indicators, thefront panel pushbutton contacts of theBA304G-SS-PMandBA324G-SS-PMarewithintheruggedindicator,andhenceinsidetheExtpanelenclosure.ThereforewheninstalledinanExtenclosurearuggedBA304G-SS-PMorBA324G-SS-PM indicator does not require protectionby a Zener barrier, galvanic isolator or intrinsically safeoutputfromassociatedapparatusbutshouldcomplywithrequirements of IEC 60079-31 Equipment dust ignitionprotectionbyenclosure.

The4/20mAcableshouldbesealedbyaglandwhere itenterstheExtenclosureandthecablescreenshouldbeearthed in thesafeareatoacommonpointsuchas theplant’sequipotentialconductor.Topreventfaultcurrentsfromotherequipment installedwithin theEx tenclosureflowing to earth via this cable screen the screen shouldbe insulated in the hazardous area and should not beconnectedtotheExtenclosure.


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Application Guide AG300 Issue 15 - BEKA€¦ · Description of ATEX & IECEx dust certification 5.1...

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