Riken Keiki GD-F4A-1 User manual

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PT2E-1512
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RequestfortheCustomers
•Readandunderstandthisoperatingmanualbeforeusingthedetectorhead.
•Usethedetectorheadinaccordancewiththeoperatingmanual.
•Regardlessofwarrantyperiod,weshallnotmakeanyindemnificationforaccidentsanddamage
causedbyusingthisproduct.
Theindemnificationshallbemadeonlyunderthewarrantypolicyofproductsorparts
replacement.
•Becausethisisasafetyunit,aregularmaintenanceforeverysixmonthsanddailymaintenance
mustbeperformed.
•Ifanyabnormalitywasfoundinthedetectorhead,notifythemtoRIKENKEIKIimmediately.
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OPERATIONANDMAINTENANCEMANUAL
FOR
RIKENOXYGENGASDETECTORHEAD
GD-F4A-1

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[CAUTIONSONOPERATION]
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Thisisafixedtypegasdetector(head)andalarminstrumenttodetectoxygengasinair.The
gasalarminstrumentisasafetyinstrument,notananalyzernormeasuringinstrumenttomake
quantitativeandqualitativeanalysisormeasurement.
Pleaseunderstandfollowingpointsandusethisdetectorheadcorrectly.
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1. The indication on this detector has some changes against fluctuation of atmospheric
pressure.Especially,takecareaboutalarmactionatthetimeofdepressioncausedby
typhoon.
Itmayalsofluctuateagainsttheenvironmental(temperature,humidity,etc.)changearound
detectorhead.
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2.Alarmlevelforgasalarminstrumentshallbesetwithintheperformanceoftheinstrument.
Ourstandardalarmlevelis18%byvolumeforthepreventionofoxygendeficiency.
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3.Thisisnotcontrolequipment,butasafetyinstrument.
Usethealarmcontactfromgasalarminstrumentonlyforexternalalarmlightorbuzzer.
Andtheanalogoutputsignalshallbeusedonlyforexternalindicatororrecorder.
Wedonotassumeliabilityforanyaccidentordamagecausedbyothercontrolpurposethan
theabove.
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4.Tomaintaintheperformanceofthisgasdetector,theregularmaintenanceserviceincluding
theregularpartsreplacementandadjustmentdescribedinthismanualshallberequired.
Alsoevery6monthsregularmaintenanceandgascalibrationarerequiredsincethisisa
safetyinstrument.
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TABLEOFCONTENTS
１．OUTLINEOFTHEPRODUCT
１−１． Preface……………………………………………………………………… 1
１−２． Purposeofuse……………………………………………………………… 1
１−３． DefinitionofDANGER,WARNING,CAUTIONandNOTE ………………… 1
２．IMPORTANTINSTRUCTIONSFORTHESAFETY
２−１． Dangercases………………………………………………………………… 2
２−２． Warningcases………………………………………………………………… 2
２−３． Cautioncases………………………………………………………………… 2
２−４． Cautionforexplosionproof(Incaseofintrinsicallysafedesign)…………… 2
３．PRODUCTCOMPONENTS
３−１． Externaldrawing……………………………………………………………… 3
３−２． Nameofeachpartandfunctions…………………………………………… 4
３−３． Systemcomposition………………………………………………………… 4
４．HOWTOUSE
４−１． Beforeusingthedetectorhead……………………………………………… 7
４−２． Precautionsforinstallationpoints…………………………………………… 7
４−３． Maintenancespace………………………………………………………… 7
４−４． Howtoinstall………………………………………………………………… 8
４−５． Cautionatwiringconstruction……………………………………………… 8
４−６． Applicablecable…………………………………………………………… 8
４−７． Exampleofcableconnection……………………………………………… 8
４−８． Cautionatpipingworks……………………………………………………… 10
４−９． Exampleofpipingconnection……………………………………………… 10
５．HOWTOOPERATE
５−１． Preparationforstartup…………………………………………………… 12
５−２． Howtostartthedetectorhead…………………………………………… 12
５−３． Howtoexit…………………………………………………………………… 12
６．MAINTENANCE
６−１． Maintenanceintervalsanditems…………………………………………… 13
６−２． Calibration
６−２−１． Requiredkitandtoolsforcalibration…………………………… 14
６−２−２． Performingazeroadjustment…………………………………… 14
６−２−３． Performingaspanadjustment…………………………………… 14
６−３． Replacingthesensor
６−３−１． Replacementintervalsofthesensor…………………………… 15
６−３−２． Howtoreplacethesensor……………………………………… 15
６−４． Storageortreatmentwhennotinuseforalongperiod………………… 16
６−５． Listofrecommendablesparepartsforregularreplacement…………… 16
７．MEASURESATABNORMALCASE
７−１． Respondingtotroublealarm……………………………………………… 17
７−２． Beforeitisthoughttobeatrouble………………………………………… 17
８．DEFINITIONOFTERMS…………………………………………………17
９．PRODUCTSPECIFICATIONS
９−１． Standardspecifications…………………………………………………18
９−２． Standardaccessories……………………………………………………18
９−３． Optionalaccessories……………………………………………………18
１０．DETECTIONPRINCIPLE……………………………………………… 19

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1
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１．OUTLINEOFTHEPRODUCT 
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１−１．Preface
ThankyouforpurchasingourfixedtypeOxygenDetectorHeadGD-F4A-1.
First of all, verify that the model number of this product is identical with specifications
describedinthismanual.ThismanualisaguidetooperationoftheGD-F4A-1. Allparsons
whousethisdetectorforthefirsttimeandwhohaseverusedthisdetectorarerequestedto
readthroughthemanualtounderstandthecontentbeforeuse.
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１−２．Purposeofuse
Thisisasuction(flow-through)typeoxygendetectorheadapplyingthegalvaniccelltype
oxygensensorandisusedincombinationwithindicator/alarmunittoshowoxygencontent.
Readtheoperatingmanualforindicator/alarmunitaswellasthismanual.
Thisunitisdesignedasdrip-proofconstructionforoutdoorinstallation.
Also,itcanbeusedasintrinsicallysafesystemincombinationwithzenerbarrier(option)tobe
abletoinstallinhazardousarea.
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１−３．DefinitionofDANGER,WARNING,CAUTIONandNOTE 
Thismanualcontainsthefollowingheadingstoensurethesafeandeffectiveoperation.
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This message indicates that improper handling may cause serious
damageonlife,healthorassets.
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Thismessageindicatesthatimproperhandlingmaycauseserious
damageonhealthorassets.
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Thismessageindicatesthatimproperhandlingmaycauseminordamage
onhealthorassets.
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Thismessageindicatesadviceonhandling.
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DANGER
WARNING
CAUTION
*NOTE

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2
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２.IMPORTANTINSTRUCTIONSFORTHESAFETY 
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２−１．Dangercases
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２−２．Warningcases
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２−３．Cautioncases 
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２−４．Cautionforexplosionproof (Incaseofintrinsicallysafedesign)
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Incaseofnon-explosionpoofsystem,donotusethisunitattheplacewherecombustiblegas
mayexist.
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・Donotcutthewireforprotectivegroundbothinsideandoutsideofinstrument.Or,donot 
disconnecttheconnectionofthegroundterminals.
・Beforestartingtheoperation,checkifanydefectisnotfoundontheprotectivegrounding.
・Ifthereisanydefectontheprotectivefunctionssuchasprotectivegrounding,donotstartthe
operation.
・Itisverydangerousiftheinstrumentgivesoxygendeficiencyalarm.
Takeappropriatemeasuresbasedonyourjudgmentatthattime.
・Performgascalibrationatproperinterval.
・Donotchangeorremodelthecircuit/structureofthisunit.
・Donotdisassemblethesensorsincethereisaelectrolyteinside.
Ifyourfingertouchestheelectrolyte,washyourfingerawaywithwaterimmediately.
WARNING
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・Donotuseawalky-talkyaroundtheinstrument.
Theindicationmightbeaffectedbytheelectromagneticwavegeneratedbythewalky-talkyifitis
usedneartheinstrument.Whenthewalky-talkyisused,beawayenoughfromtheinstrument
nottoaffect.
・Donotcontrolotherequipmentbyusingoutputsofthisdetector.
Thisisnotcontrolequipment. Itisprohibitedtocontrolotherequipmentbyusingoutputsof
thisdetector.
CAUTION
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・Donotusethisdetectorheadexpectforthemeasurementofoxygencontentinamixtureofair
andcombustiblegasorvapors,oramixtureofairandtoxicgases.
・Whencleaningthisunit,donotusedryclothbutusethewetclothnottochangethestatic
electricityonplasticpart.
CAUTION
DANGER

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3
３．PRODUCTCOMPONENTS 
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３−１．Externaldrawing
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Cableinlet
Cableinlet Sensor Gasinlet
Protective
ground Gasoutlet
(For U-bolt)
Cableinlet Sensor Gasinlet
Protective
g
round Gasoutlet
(
ForUbolt
)
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３−２．Nameofeachpartandfunctions
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①Oxygensensor : Galvanictypesensortodetectoxygencontent.
②Sensorretainer : Thisisaretainertoholdtheoxygensensor
(equippedwithfilterinside).
③Sensorlead : Leadwiresforoxygensignaloutputs.
④Terminalstrip : Relayedterminalforsensorleadandexternalcable.
⑤Cablegland : Entrancetoleadthecable(φ8〜φ11mm)fromoutside.
⑥Hinge : Hingeforfrontdoor.
⑦Lock : Lockforfrontdoor.
⑧Mountinghole : Mountingholetofixthisunitonthewallsurface.
⑨Protectiveearthbolt : Boltforprotectivegrounding.
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３−３．Systemcomposition
(1)Intrinsicallysafesystem
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Detector
head
Zenerbarrier
Indicator
/alarm
unit
Hazardousarea Non-hazardousarea
CVVS-2C1.25mm2orequivalent(max600m)cable
⑥
⑨ ⑤
③
⑦
①
②
④⑧

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5
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１．Theoxygendetectorshallbeusedasfollowingcomposition.
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２．Thesafetyretainertobeconnectedwithoxygendetectorshallhavelinearcharacteristicsand
bepassedthetypeapprovalasitis.
Alsoitshallsatisfythefollowingconditions.
(1) Ratingofsafetyretainer
Maxvoltageofintrinsic-safetycircuit:Below28V
Maxcurrentofintrinsic-safetycircuit:Below600mA
Maxpowerofintrinsic-safetycircuit:Below0.75W
(2) Performancedivisionandgroup
Performancedivision:ia
Group:ⅡC
(3) Relationsbetweenallowableinductance(Lo)andallowablecapacitance(Co)
ofintrinsic-safetycircuit,andexternalwiringinductance(Lw)andcapacitance(Cw)
ofintrinsic-safetycircuit.
Lo≧Li+Lw
Co≧C+Cw
(4) Whenmakingwiringconnectionforintrinsic-safetycircuit,takecarenottoinduce
anelectriccurrentandvoltagewhichwillspoiltheperformanceofintrinsicallysafe
bytheelectromagneticinductionorelectrostaticinductiontotheintrinsic-safety
circuit.


WARNING
！
Hazardous
area Non-hazardous
area
Safetyretainer
Oxygendetector
Ｌｉ≒0
Ｃｉ≒0
≒0showsanegligiblevalue
Ｌｉ
Ｃｉ Ｌｏ Ｃｏ
Ｌｗ
Ｃｗ



6

(2)Non-explosionproofsystem













(3)Componentinsidedetectorhead




Drip-proofhousing
Sensorlead
Terminalstrip
Cablegland
Shieldedcable
Oxygen
sensor
Gasinlet
Gas outlet
Detector
head
Indicator/alarm unit
Non-hazardousarea Non-hazardousarea
CVVS-2C1.25mm2
orequivalent(MAX600m)



7

４．HOWTOUSE

４−１．Beforeusingthedetectorhead
Allpersonswhousethisdetectorforthefirsttimeandwhohasevenusedthedetectorare
requestedtofollowalltheinstructionsforusecarefully. Ifnot,theinstrumentmaybedefective
andcorrectgasdetectionmaynotbeperformed. 


４−２．Precautionsforinstallationpoints
Wheninstallingthisdetector,notethefollowingpoints.


Donotinstallthedetectorheadandcableatthefollowingpoints.
・Placetogetdirectraysofthesun.
・Placesclosedtohightemperatureand/oremissionofelectromagneticwave.
・Placewithvibrationorshocks.
・Placewherethemountingpartisweakanditiseasytocomeout.
・Placewhereitisdifficulttomakemaintenanceandinspection.
・Placeunabletosecuregrounding.
・Placeswherethetemperatureisdrasticallychanged.
・Placesexceedingoperatingtemperatureandhumidity.


４−３．Maintenancespace
Acertainmaintenancespacemustbesecuredaroundthedetectorhead,sothatthemaintenance
staffcanperformthesafeandcorrectmaintenancework.Paydueattentiontosecurethisspace
duringworkplanandexecution.
WARNING



8



４−４．Howtoinstall 
(1) Mountingtothewallsurface
Mountthedetectorheadtoaflatsurface(wall
surface,etc)witheitherM6boltsorM10bolts
throughmountingholes.Referto「3-1.External
drawing」formountingpitch.
(2) Mountingtothepole
Theunitcanbemountedtothepole(2Bpipe)
byusingtheoptionalU-boltsshowninright
figure.
(3) Installationtotheoutdoors
Foroutdoorinstallation,optionaldrip-proofcover
isrequiredtokeepreliabledetectionalthoughthis
isadrip-proofdesign.ContactRIKENKEIKICo.,
Ltd.


４−５．Cautionatwiringconstruction 










４−６．Applicablecable
Signaltransmission :CVVS1.25mm2,2Corequivalent
Transmissiondistance :Within600matfulllengths
CableO.D.  :φ8-φ11mm

４−７．Exampleofcableconnection

(1)Incaseofnon-explosionproofsystem
①Leadtheapplicablecablethroughcableinlet
andconnecttotheterminalstrip.
②Connecttheothersideofthecabletothe
indicator/alarmunitside.
③Connecttheshieldʼsdraingroundonthe
indicator/alarmunitside.




・Whenmakewiringconstruction,takecarenottodamagetheinternalelectronicscircuit.
・Whenhandlethedetectorunit,putitathorizontalposition. Ifputitvertically,ittends
tofallanddamagethedetector.
・Powercableandsignalcableshallnotbelaiddowntogetherwithmotivepowercable
suchasmotor,etc.
・Whenusetwistedcable,takecarenottocontactapartofcorecablewithothercore
cable.
CAUTION
！

ケーブルの接続
ケーブル
−＋
端子台
センサ
リード線
Sensor lead
wire
Terminal
stri
p
Cableconnection
Mountingtothepole
2B pipe
（O.D. 60.5mm）
U-bolt
（Nominal
diameter 50B）
Cable



9
(2)Incaseofintrinsicallysafesystem
Youcanbuildtheintrinsicallysafesystembyadding
optionalzenerbarrierbetweendetectorheadandindicator/alarmunit.
①Leadtheapplicablecablethroughcableinletandconnecttotheterminalstrip.
②Connecttheoptionalzenerbarrierbetweenthisunitandindicator/alarmunitat
non-hazardousarea.(Seebelowfig.)
③Connecttheothersideofthecabletotheindicator/alarmunitside.
④Connecttheshield’sdrainwiretogroundontheindicator/alarmunit.














































・Donotalter,noｒremodeltheparts,etc.
・Usethecircuitbreakerasforthepowerofindicator/alarmunit.Alsoitshallbemounted
nearbyindicator/alarmunitandbespecifiedthatitisforpowerinterruptionof
indicator/alarmunit.

・GroundthezenerbarrierseparatelycorrespondingtotheA-classgroundingwithground
resistanceof10Ωorless.
・Usethespecifiedcable.
・Forsysteminstallation,operationandmaintenance,takecarenottodamagetheintrinsically
safedesign.
・Thepoweroftheindicator/alarmunitshallbeturnedonaftercompletionofallwirings.If
eachwiringiscarriedoutinthepoweroncondition,short-circuitbetweenterminalsoran
electricalshockmaybeoccurred.
*NOTE
・Whenwiring,readtheoperatingmanualfortheconnectedindicator/alarmunit.
WARNING
CAUTION
！
Exampleofintrinsicallysafesystem
D
e
t
e
c
t
o
r

h
e
a
d

Hazardousarea Non-hazardousarea
１
３
２４
I
n
d
i
c
a
t
o
r
/
a
l
a
r
m

u
n
i
t

Zener
barrier（MTL761Pac）
max.600m
Connectioncable Connection
cable



10

４−８．Cautionsatpipingworks


























４−9．Exampleofpipingconnection
Gasinlet/outletfittingofthisunitisRc1/8femalescrewandprovidedwithbrasscoupling.
Applicablepipingisφ8(O.D.)-1tcopperpipe.Securethepipingconnectionsnottoleak.
Thepipingmaterialwillbechangeddependingoncorrosivegascontainedinasampledgas.In
suchcase,contactRIKENKEIKICo.,Ltd.

(1)Incaseofpumpsuction











・Thisunitisdesignedtosamplethegasinanatmosphericpressure.Donotgiveanexcessive
pressuretogasinletandoutletofthisunit.
・Connecttheexhaustpipetothegasoutletlocatedatthebottomofthisunitandexhaust
thesampledgastoanareaknowntobenon-hazardous.
WARNING


・UseΦ8(O.D)-1tcopperpipeandsoonforpiping.
・Carryoutpipingworksasstraightaspossible.
Excessivelyhighloadmaycauseburdenonthesuctionpump,shorteningtheeffectivelifeof
thepump.
Whenbendsthepipe,secureR(radiusofcurvature)enoughtoavoidloadingtothepiping.
・Determinethesuctionsidepipinglengthwhileconsideringtheresponsetime.Whenthe
gasissampledfromthepipingend(gasdetectionpoint),theresponsetimeofthegas
detectionsensoritself+delaytimecausedbythepipinglengthbecomesequivalenttothe
detectorresponsetime.
・Besuretoattachthegassuctionportattheendofgasdetectionpoint.
・Besuretoputdustfilterinfrontofgasdetector.Ifsampledgascontainswaterand
corrosivegases,removaldeviceisrequiredseparately.
CAUTION
！
Detection
p
oint
GD-F4A-1
Gas OUT
1.0±0.3L/min
Dustfilter Pump Flowcontrol
valve
P
Flowmeter



11

(2)Incaseofpressurizedsamplegas










(3)Incaseofaspiratorsuction















•It is also possible to apply air aspirator unit to sample the gas by utilizing
instrumentationair.Inthismethod,pressuretothesensormustbekeptas
smallaspossibleandmakeitto-26hPaatamaximum.
Astheloadtooxygensensorishighonthismethod,aspiratorsuctionmethod
shallbeusedonlywhenthepumpcannotbeused.
•Ifthesamplegaspressurewouldfluctuate,usetheconstantflowratecontrol
valvetokeeptheconstantflowrate.
•Exhaustthesampledgastoopenairinprinciple. Whenmakepipingtoexhaust
sidenecessarily,choosethepipingdiametertokeepthepressurelossduetothe
lengthofpipingwithin13hPa.
Dustfilter
Detection
p
oint
GD-F4A-1
Gas OUT
1.0±0.3 L/min
Flowcontrolvalve
Flowmeter
CAUTION
！
Detection
p
oint
GD-F4A-1 Instrumentation air
Air consumption：1〜3NL/min
Pressure：0.1〜0.34MPa
Dustfilter Flow control
valve
Aspirator
Flowmeter



12

５．HOWTOOPERATE

５−１．Preparationforstartup
Beforemakingpoweron,takecareofthefollowing. Ifdonotkeepthis,thereisthedangerof
electricalshockanddamageofinstrument.









５−２．Howtostartthedetectorhead
①Thisdetectorheaddoesnotequipapowerswitch. Analogoutputsofoxygensensorare
transmittedtotheindicator/alarmunitdirectlythroughtheconnectedcable.Asfaras
thecablehasbeenconnectedcorrectly,thissystemstartsoperationbyputtingonthe
powerswitchinindicator/alarmunit.
②Letthegasflowtobesampledtothisunitbyturningonthepumpswitchetc.
③Adjusttheflow-ratetoleadsampledgasto1.0L±0.3mL/min.
④Besuretoperformgascalibrationatthetimeofnewinstallation. Correctreadingmay
notbeobtainedbeforegascalibration.
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５−３．Howtoexit
①Stopthesamplegassupplytothisunitbyturningoffthepumpswitch,etc.
②Thissystemstopsoperationbyputtingoffthepowerinindicator/alarmunit,sincethis
unithasnopowerswitch.


・Makeprotectivegrounding.
・Checkthatthewiringwithouterunitismadecorrectly.
・Checkthatthesupplyvoltageiswithintherating.
・Checkthattheratedfuseisused.
WARNING


・Atthenewinstallation,adjustthereadinginindicator/alarmunitaccordingto「6-2.
Calibration」.Adjustmentisdonebyindicator/alarmunitsincethedetectorheadhas
no function for adjustment.  Refer to operating instructions for the connected
indicator/alarmunit.
CAUTION
！ 

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13
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６．MAINTENANCE

Gasdetectionandalarminstrumentiskeptincontinuousoperationoveralongtimeandmust
performavitalroleasasafetydevice.Forthispurpose,periodicalinspectionmustbemade.
TheHigh-pressureGasSafetyActinJapansetsforththeobligationofperiodicalinspectionof
thegasdetectionandalarminstrument.
-MaintenanceContract‒
Besuretoperformtheregularmaintenancesincethisisaninstrumentforsecurityand
safety.Ifthisdetectorheadfoundsdefective,contactRIKENKEIKIimmediately.

６−１．Maintenanceintervalsanditems
Themaintenanceincludesadailymaintenancewhichapersoninchargeofcontrolandoperationof
thegasdetection instrument performs maintenancebeforework onceaday,anda monthly
maintenancecarriedoutonceamonth,andperiodicalmaintenanceconductedbytheservice
personnel designated by manufacturer.  The maintenance items are confirmation of lights,
concentrationindicationandalarmfunctionontheindicator/alarmunitside.Itisalsonecessaryto
carryoutgascalibrationatleastevery6months.ThelawinJapansetsforththattheunitmust
issueanalarmduringthecircuitmaintenancerelatedtoalarmwhileprovidingnormaloperation,at
least,onceamonth.
Tomaintainthesafetyoperationofthegasdetectioninstrument,itisrecommendedtokeepthe
maintenancecontractwithourauthorizeddistributorforregularmaintenance,adjustmentand
overhauletc.includingthegassensitivityadjustment(gascalibration).
Forthedetailofmaintenancecontract,contactRIKENKEIKI..
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
WARNING
！
*NOTE
・Besuretoinformsectionsconcernedbeforehandwhenperformingalarmtestor
gascalibration.Fortheequipmentconnectedwithoutputsignalfrom
indicator/alarmunit,performthemafterdisconnectingtheoutputsignal.
・Specialtrainedengineerforgasdetectioninstrumentcanperformmaintenance
workaccuratelyandefficiently.
・Then,itisrecommendedtocontactRIKENKEIKIformaintenance.

・Thisisasafetyinstrumentandthemaintenanceevery6monthsormoreis
mandatorytoensurethesafety.Iftheunitisusedbycontinuouslywithout
maintenance,thesensorsensitivitymaychange,resultinginfailureofcorrect
detection.

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14
６−２．Calibration 
Performgascalibrationatnewinstallation,6monthsmaintenanceandsensorreplacement.

６−２−１．Requiredkitandtoolsforcalibration
 Preparefollowingjigsandtoolstoperformzeroandspanadjustments.
•Calibrationgas(standardgasforzeroandspan)
•Gassamplingbagforcalibrationgas.
•Gassamplingbagforexhaustgas.
•Suctionpumptoleadcalibrationgas
•Flowmeterwithflowcontrolvalve(enabletocontrol1.0L/min).

６−２−２．Performingazeroadjustment 
①Packthezerogas(Nitrogenmorethan99.9vol%)intogassamplingbag.
②Disconnectpipingforbothgasinletandgasoutletofthisunit.
③Connectflowmeter（withflowcontrolvalve）andsuctionpumptothedetectorhead.
Turnonthepumpandadjustthereadingofflowmeterto1.0±0.3L/min.
④ConnectgassamplingbagforcalibrationtotheINsideofthepumpandgassamplingbag
forexhaustgastotheoutletofthisunitrespectively.
⑤After reading by indicator/alarm unit gets stable, adjust the reading to zero with
respectivepotentiometerofindicator/alarmunit.
⑥Stopthesupplyofzerogas,disconnectgassamplingbagforcalibrationandconfirmthat
theoxygenreadingreturnsto20.9vol%.
⑦Returndisconnectedpipingtowheretheywere(completionofzeroadjustment).

６−２−３．Performingaspanadjustment 
①Pack the span gas (fresh air for oxygen deficiency alarm instrument and their
concentrationisaroundpresetalarmlevelforotherpurpose)intogassamplingbag. 
For simple calibration, you may be possible to use an ambient air as span gas 
containing20.9vol%O2providingthattheambientpressureis1atm(1000±50hPa) 
andcontaminationinairisnegligibleagainstspangasconcentration.
②Disconnectpipingforbothgasinletandgasoutletofthisunit.
③Connectflowmeter（withflowcontrolvalve）andsuctionpumptothedetectorhead.
Turnonthepumpandadjustthereadingofflowmeterto1.0±0.3L/min.
④ConnectgassamplingbagforcalibrationtotheINsideofthepumpandgassamplingbag
forexhaustgastotheoutletofthisunitrespectively.
⑤Afterreadingbyindicator/alarmunitgetsstable,adjustthereadingtothespangas
concentrationwithrespectivepotentiometerofindicator/alarmunit.
⑥Stopthesupplyofspangas,disconnectgassamplingbagforcalibrationandconfirmthat
theoxygenreadingis20.9vol%.
⑦Returndisconnectedpipingtowheretheywere(Completionofspanadjustment).
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15
６−３．Replacingthesensor 
６−３−１．Replacementintervalsofthesensor
Tomaintainthereliabilityofthemeasurement,itisrecommendabletoreplacethesensor
periodically.  Our oxygen sensor has an enough life span.  However, the actual life is
depending on the operating conditions.  Then, replace the sensor once a year as the
tentativedeadlineforthereplacementcycle.
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６−３−２．Howtoreplacethesensor
①  Verify that the indicator/alarm unit is off. If the sensor is disconnected, the
indicator/alarmunitissuesanalarm.
② Turnalockofdetectorheadandopenthefrontdoor.
③ Loosentwoscrewsatthetopofterminalstripanddisconnecttwolead(blackandwhite)
wires.
④ Loosenthescrewforsensorstopperandtakeoffthesensorstopper.
Pulloutthesensorupwardfromtheholder
⑤ Insertnewsensorintotheholderandpushthesensoruntilitcomestotheend.
 Mountthesensorstopperandfixitwithscrew.
⑥ Connectblackandwhitesensorleadwirestotheterminalstrip.Connectwhitewireto
positive(+)terminalandblackwiretonegative(-)terminalrespectively.
⑦ Closethefrontdoorofthedetectorheadandfastenalock.
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

・Besuretocarryoutgascalibrationaftersensorreplacement.Ifnot,correctgasdetection
maynotbeperformed.
CAUTION
！
Lead-wire(black)
Negativesidecablecore
Lead-wire(white)
Sensor
Sensorstopper
Sensorholder
PositivesidecablecoreCable

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16
６−４．Storageortreatmentwhennotinuseforalongperiod

Oxygensensorisakindofcellandwillcontinuetoconsumeitslifeeventhoughitisnot
used.Whendetectorheadisnotusedforalongperiod,takeoutthesensorfromdetector
headandstoreitatfollowingenvironmenttomakelowertheconsumptionofsensor.

・Environmentoflowtemperature(5〜10℃)
・Environmentoflowoxygencontent
(Putasensorintothecontainerandsealoffthecontainer.)
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６−５．Listofrecommendablesparepartsfor
regularreplacement

No. Nameofparts Inspectionfrequency Replacementinterval Qʼty/unit
1 O-ring
(sensorsideintheholder) 1year 3-6years 1
2 O-ring
(Housingsideintheholder) 1year 3-6years 1
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*NOTE
・Thereplacementintervalwillchangedependingonoperatingconditionanditdoesnot
meanthewarrantyperiod.
Replacementintervalchangesaccordingtotheresultofregularmaintenance.

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17

７．MEASURESATABNORMALCASE
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
７−１．Respondingtotroublealarm
Ifthisdetectorfoundsdefective,contactRIKENKEIKI.


７−２．Beforeitisthoughttobeatrouble


・Checkthewiringsaroundtherelatedinstrumentsaswellasthisdetectorhead.
Itmaybecausedbyimproperoperation.
・Re-checkthedetectionsystemandcontactRIKENKEIKI.
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

８．DEFINITIONOFTERMS
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 Galvaniccell
Galvaniccelltypeoxygensensorthatproducesacurrentproportionaltotheoxygencontent
permeatedthroughthemembrane. Referto「10.DETECTIONPRINCIPLE」fordetails.

 Zenerbarrier
Safetyretainerfor explosionprotection by limiting the energy of electriccurrent within a
non-ignitionlevel.

 CVVS
Thisisakindofconnectingcablebetweenindicator/alarmunitandoxygendetectorhead.
CVVSmeansa“Polyethyleneinsulatedandvinylsheathedcontrolcablewithshield”.

 Calibration
Byusingstandard(calibration)gas,adjustgasreadinginindicator/alarmunittomatchthe
calibrationgasconcentration.

Itmaybecausedbycabledisconnection,shortcircuit,etc. 