Riken Keiki GD-F3A-1 User manual

PT2E- 1493
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RequestfortheCustomers
•Readandunderstandthisoperating manual before usi ng 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
mus t  be  pe r fo r me d. 
•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- F3A- 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 al arm i nst rument  i s a safet y i nst rument ,  not  an anal yz er normeasuringinstrumenttomake
quant i tat i ve and qual i t at i ve anal ysi s or measurement .  
Pleaseunderstandfollowingpointsandusethisdetectorhead correctly.
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1.  The i ndi cat i on on t hi s detect or has some changes agai nst fl uctuation of atmospheric
pressure.  Especi al l y,  t ake care about al arm act i on at t he t i me of depression caused by
typhoon.
Itmayalsofluctuateagainsttheenvironmental(temperature,humi di ty, etc.) change around
det ect or head. 
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2.  Al arm l evel  for gas al arm i nst rument shal l  be set  wi t hi n t heperformanceoftheinstrument.
Ourstandardalarmlevelis18%byvolumeforthepreventionofoxygendeficiency. 
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3.  Thi s i s not  control  equi pment ,  but  a safety i nst rument. 
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indemnificationforanyaccidentordamagecaused by other control
purpose t han t he above. 
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4.  To mai ntai n the performance of thi s gas detect or,  the regul armaintenanceserviceincluding
theregularpartsreplacementandadjustmentdescribedinthismanual  s hal l  be  re qui r e d. 
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．P R O D U C T  O UT L I NE 
１−１． Preface ……………………………………………………………………… 3
１− ２． A ppl i c a t i o n  f o r  u s e  … … … … … … … … … … … … … … … … … … … … … …  3
１−３． Identificationofeachsignalword ………………………………………… 3
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２．I MP O R T A NT  I NS T R UC T I O N S  F O R  T H E  S A F E T Y 
２−１． Dangeritems………………………………………………………………… 4
２− ２． Wa r n i n g i t e ms … … … … … … … … … … … … … … … … … … … … … … … … …  4
２−３． Cautionitems………………………………………………………………… 4
２− ４． C a u t i o n s  f o r  t h e  e x pl o s i o n proof (I n case of i ntri nsical lysafedesign)…… 4
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３．P R O D U C T  F U N C T I O N 
３−１． Externaldrawing……………………………………………………………… 5 
３− ２． N a me  o f  e a c h  pa r t  a ndfunctions……………………………………………      6
３− ３． S y s t e m c o mpo s i t i o n  … … … … … … … … … … … … … … … … … … … … … …  6
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４．HO W T O  US E 
４−１． Beforeoperation……………………………………………………………… 9
４−２． Installationplace …………………………………………………………… 9
４− ３． Ma i n t e n a n c e  s pa c e  … … … … … … … … … … … … … … … … … … … … … …  9
４− ４． I n s t a l l a t i o n  wo r k s  … … … … … … … … … … … … … … … … … … … … … … …  9
４− ５． C a u t i o n  a t  wi r i n gconstruction  …………………………………………… 10
４− ６． A ppl i c a bl e  c a bl e  … … … … … … … … … … … … … … … … … … … … … … …  10
４− ７． E x a mpl e  o f  c a bl e  c o nn e c t i o n  … … … … … … … … … … … … … … … … … …  10
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５．O P E R A T I O N ME T H O D 
５− １． P r e pa r a t i o n  be f o r e  s t a r t  up  … … … … … … … … … … … … … … … … … …  12
５−２． Startup……………………………………………………………………… 12
５− ３． S t o ppi ng t h e  o pe r a t i o n  … … … … … … … … … … … … … … … … … … … …   12
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６．MA I N T E N A N C E  A N D  I N S P E C T I O N 
６− １． I n s pe c t i o n  f r e q u e ncyanditems …………………………………………… 13
６− ２． C a l i br a t i on 
６− ２− １． R e qu i r e d ki t  a n d t o o l s  f o r  c a l i br a t i o n… … … … … … … … … … …  14
６− ２− ２． P e r f o r mi n g a  z e r o  a dj u s t me n t  … … … … … … … … … … … … … …  14
６− ２− ３． P e r f o r mi n g a  s pa n  a dj u s t me n t … … … … … … … … … … … … … …  14
６− ３． R e p l a c i n g t h e  s e n s o r  
６− ３− １． R e pl a c e me n t  f r e qu e n cyofthesensor…… ………… … ………… 15
６− ３− ２． R e pl a c i n g t h e  s e n s o r  … … … … … … … … … … … … … … … … …  15
６−４． Storageortreatmentwhennotinuseforalongperiod………………… 16
６− ５． L i s t  o f  r e c o mme n da bl e  s pa r e partsforregularreplacement ……………  16
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７．ME A S U R E S  A T  A B N O R MA L  C A S E 
７−１． Respondingtotroublealarm ………………………………………………  17
７− ２． B e f o r e  i t  i s  t h o u gh t  tobeatrouble………………………………………… 17
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８．DEFINITIONOFTERMS…………………………………………………17

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2
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９．P R O D UC T  S P E C I F I C A T I O N S 
９− １． S t a n da r d s pe c i f i c a t i o n s   … … … … … … … … … … … … … … … … … … …18
９− ２． S t a n da r d a c c e s s o r i e s  … … … … … … … … … … … … … … … … … … … … 18
９− ３． O pt i o n a l  a c c e s s o r i e s  … … … … … … … … … … … … … … … … … … … …  18
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１０．DETECTIONPRINCIPLE……………………………………………… 19

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3
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１．P R O D U C T  O UT L I N E 
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１−１． Preface 
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ThankyouforpurchasingourfixedtypeOxygenDetectorHeadGD-F3A-1.
First of all, verify that the model number of this product is ident i cal  wi t h speci fi cat i ons
descri bed i n thi s manual .  Thi s manual  i s a gui de t o operati on oftheGD- F3A- 1.  Allparsons
who use uni t  for the fi rst ti me and who has ever used thi s uni t arerequestedtoreadthrough
themanualtounderstandthecontentbeforeuse.
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１−２． Appl icati on for use
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Thisisadiffusion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
instruction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 i ncombinationwithzenerbarrier (option)to
be abl e to i nst al l  i n haz ardous area.     
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１− ３． I d e n t i f i c a t i o n  o f  e a c h  s i gn a l  wo r d 
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Thismanualcontainsthefollowingheadingstoensurethesafeandeffectiveoperation.
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Indicatesanimminentlyhazardoussituationwhich,if notavoided,
wi ll  resul t i n death or seri ous i njury or seri ous damage t o the
product. 
Thissignalwordistobelimitedtothemostextremesituation.
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Indicatesapotentiallyhazardoussituation which, if not avoided,
couldresultseriousinjurytothehumanbodyorobject.
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Indicatesapotentiallyhazardoussituationwhich,ifnotavoided,may 
resultinminorormoderateinjuryorsomedamagetothehumanbody
or objects. I t may al so be used to al ert against unsafe practices. 
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Thismeans“ADVICE”regardingoperation.

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DANGER
WARNING
CAUTION
*NOTE

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２− １．D a n ge r  i t e ms 
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２− ２．Wa r n i n g i t e ms 
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２− ３．C a u t i o n  i t e ms 
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２− ４．C a u t i o n f o r  e x pl o s i o n  pr o o f  
(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  e x i s t . 
２.  I MP O R T A N T  I NS T R U C T I O N S  F O R  T H E  S A F E T Y 
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・D o  n o t  c u t  t h e  w i r e  f o r  p r o t e c t i v e  g r o u n d  b o t h  i n s i d e  a n d  o u t s ide of instrument. Or, do not 
di sconnect  the connecti on of the ground termi nals.
・B e f o r e  s t a r t i n g  t h e  o p e r a t i o n ,  checkifanydefectisnotfound on t he protect i ve groundi ng. 
Ifthereisanydefectontheprotectivefunctionssuchasprotectivegrounding,donot startthe
operation.
・I t  i s  v e r y  d a n g e r o u s  i f  t h e  i n s t r u m e n t  g i v e s  o x y g e n  d e f i c i e n c y alarm. 
Takeappropriatemeasuresbasedonyourjudgmentatthattime.
・P e r f o r m  g a s  c a l i b r a t i on at proper interval .
・D o  n o t  c h a n g e  o r  r e m o d e l  t h e  c ircuit/structureofthisunit.
・D o  n o t  d i s a s s e m b l e  t h e  s e n s o r  s i n c e  t h e r e  i s  a  e l e c t r o l y t e  i n s ide.
Ifyourfingertouchestheelectrolyte, washyourfingerwaywithwaterimmediately.
WA R N I N G 
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・D o  n o t  u s e  a  w a l k y - t a l k y  a r o u n d  t h e  i n s t r u m e n t . 
Theindicationmightbeaffectedbytheelectromagneticwavegenerated by the
wal ky- t al ky i f i t is used near theinstrument.  Whenthewalky- talkyisused,beaway 
enoughfromtheinstrume nt  not  t o affe c t . 
・D o  n o t  c o n t r o l  o t h e r  e q u i p m e n t  b y  u s i n g  o u t p u t s  o f  t h i s  d e t e c t or.
Thisisnotacontrolequipment.Itisprohibitedtocontrolotherequipmentbyusing
outputsofthisdetector.
CAUTION
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・D o  n o t  u s e  t h i s  d e t e c t o r  h e a d  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.
・W h e n  c l e a n i n g  t h i s  u n i t ,  d o  n o t  u s e  d r y  c l o t h  b u t  u s e  t h e  w e t  cloth not to change the static 
electricityonplasticpart. 
CAUTION
DANGER

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5
３．P R O D U C T  F U N C T I O N 
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３−１． Externaldrawing 
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Pr ot ect i ve ground
Ca b l e  i nl e t 
(forUbolt)
Se ns or

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6
３−２． Name of each part and functions
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① Oxygensensor :Galvanictypesensortodetectoxygencontent.
② Sensorholder :Thisisaretainertoholdtheoxygensensor
(equipped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.

３−３．
Systemcomposition

(1)Intrinsicallysafesystem
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①
⑦
②
③
④
⑤
⑥
⑧
Detector
head
Zener  bar r i er 
Indicator
/alarm
unit
Ha z a r do u s  a r e a  No n - h a z a r do u s  a r e a 
CVVS1.25sq・2C or
equivalent (MAX600m)
⑨

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7
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
1. Theoxygendetectorshallbeused as fol l owi ng composi t i on. 
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2. Thesafetyretainertobeconnected with oxygen detector shal l 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 al lowable 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) Wh e n  ma k i n g wi r i n g c o n n e c t i o n  f o r  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.
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WA R N I N G 
！
Ha z a r do u s  
ar ea
No n - h a z a r d o u s 
ar ea
Saf et y r et ai ner 
Ox y g e n  d e t e c t o r 
Ｌｉ≒ 0
Ｃｉ≒ 0
≒ 0 shows a negl i gi bl e val ue
Ｌｉ
Ｃｉ
Ｌｏ
Ｃｏ
Ｌｗ
Ｃｗ

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8
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(2)Non- explosionproofsystem
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(3)Componentinsidedetectorhead
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①
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Detector
head
Indicator/alarm unit
No n - h a z a r do u s  a r e a  No n - h a z a r do u s  a r e a 
CVVS1.25sq・2C 
or equivalent (MAX600m)
Sensor  hol der 
Ox y g e n 
At mo s phe r e 
Ca bl e  gl a nd
Shi el ded cabl e
Housing
Sensor  l ead
Terminal
strip
Oxygen
sensor

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9
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4．HOW TO USE

４− １．B e f o r e  o pe r a t i o n

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
defecti ve and correct  gas det ect i on may not  be performed.  

４− ２．I n s t a l l a t i o n  pl a c e 

Thisdetectorheadisinstalledattheplaceofoxygendetectiondirectlysincethisisadiffusion
det ect or head.  
Note the following points.  


Do not install the detector head and cable at the followi ng poi nts.
・P l a c e  t o  g e t  d i r e c t  r a y s  o f  t h e  s u n . 
・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．Mai nt enance  spac e

A certain maintenance space must be secured around the detectorhead,sothatthe
mai nt e nanc e  s t a ff  c a n pe r fo r m t h e  s afe  a nd c o r re c t  ma i nt e nanc e  work.   Pay due attenti on to
securethisspaceduringworkplanandexecution.  

４− ４．I n s t a l l a t i o n  wo r k 

(1) Mount i ng t o t he wal l  surfac e
Mount  t he det ect or head t o a fl at  surfac e ( wal l  surface, 
etc) with either M6 bolts or M10 bolts through
moun t i ng ho l e s .   R e fe r  t o ”3- 1.  Ext ernal  drawi ng”for
mount i ng pi t c h. 
(2) Mount i ng t o t he pol e
Theunitcanbemountedtothepole(2Bpipe) 
byusingtheoptionalU-boltsasshowrightfigure.
(3) Installationtotheoutdoors
For outdoor installation, optional drip- proof cover is
required to keep reliable detection although this is a
dri p- proof desi gn.   Contact  authori z ed di stri but ors, 
deal ers or representat ive appoi nt ed by Ri ken Kei ki  Co. , 
Ltd.
WA R N I N G
2B pipe
（O.D. 60.5mm）
U-bolt
（Nominal
diameter 50B）
Mount i ng t o t he pol e

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10
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４− ５．C a u t i o n  a t  w i r i n g c o n s t r u c t i o n  
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４− ６．Appl i c a bl e  c a bl e 
Signaltransmission   :CVVS1.25mm
2
,2Corequivalent
Transmissiondistance  :Within600mattotal 
CableO.D.   : φ 8- φ11mm

４− ７．E x a mp l e  o f  c a bl e  c o n n e c t i o n 

(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shieldingwiretochassisground.

(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.
① Lead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 bel ow fig.)
③ Connecttheshieldingwiretochassisground.

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Exampl e of  i nt r i nsi cal l y saf e syst em


・W h e n  m a k e  w i r i n g  c o n s t r u c t i o n ,  t a k e  c a r e  n o t  t o  d a m a g e  t h e  i n t ernalelectronicscircuit.
・W h e n  h a n d l e  t h e  d e t e c t o r  u n i t ,  p ut i t at horizontal posi ti on. Ifputitvertically,ittends
tofallanddamagethedetector.
・P o w e r  c a b l e  a n d  s i g n a l  c a b l e  s h a l l  n o t  b e  l a i d  d o w n  t o g e t h e r  w ithmotivepowercable
suchasmotor,etc.
・W h e n  u s e  t w i s t e d  c a b l e ,  t a k e  c a r e  n o t  t o  c o n t a c t  a  p a r t  o f  c o r e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
wi re
Terminal
stri
p
Cableconnection
1
3
24
De t e c t o r  he a d
Indicator/alarm
uni t 
Zener barrier
（MTL761Pac）
Max. 600m
Ha z a r do u s  a r e a 
No n - h a z a r do u s  a r e a
Connectioncable Conne c t i o n
cabl e
Cable

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11
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・Donotalter,noｒ remodel theparts, etc.
・Use the ci rcuit breaker as for the power of indicator/ al arm uni t.  Alsoitshallbemounted
nearby indi cator/ alarm unit and be speci fied 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 speci fied 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instructionsfortheconnected i ndi cat or/ al arm uni t . 
WA R N I N G 
CAUTION
！

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12



５.OPERATIONMETHOD

５− １．P r e pa r a t i o n be f o r e  s t a r t  u p 

Beforemakingpoweron,takecareofthefollowing.  Ifdonotkeepthis, there is the danger
of el ectrical  shock and damage of instrument.







５− ２．S t a r t  u p

①Thisdetectorhead doesnotequipapowerswitch.  Analogoutputsofoxygensensor
are transmitted to the indicator/ alarm unit directory through the connected cable
wi thout  si gnal  conversi on. 
Asfarasthecablehasbeenconnectedcorrectly,thissystemstartsoperationby
puttingonthepowerswitchinindicator/alarmunit.

②Besuretoperformgascalibrationatthetimeofnewinstallation. 
Correctreadingmaynotbeobtainedbeforegascalibration.









５− ３．S t o ppi n g t h e  o pe r a t i o n 

Thissystemstopsoperationbyputtingoffthepowerinindicator/ alarmunit,sincethisunithas
no power switch.   











・M a k e  g r o u n d i n g . 
・C h e c k  t h a t  t h e  w i r i n g  w i t h  o u t e r  u n i t  i s  m a d e  c o r r e c t l y . 
・C h e c k  t h a t  t h e  s u p p l y  v o l t a g e  i s  w i t h i n  t h e  r a t i n g . 
WA R N I N G 


・A t  t h e  n e w  i n s t a l l a t i o n ,  a d j u s t  t h e  r e a d i n g  i n  i n d i c a t o r / a l a r m unitaccordingto“6- 2. 
Calibration”.  Adjustmentisdonebyindicator/alarmunitsincethedetectorheadhas
nofunctionsforadjustment.Refertooperatinginstructionsfor the connected
indicator/alarmunit. 
CAUTION
！

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
13

 ６．MA I N T E N A N C E  A N D  I N S P E C T I O N 

Gasdetectionandalarminstrument is kept i n continuous operationoveralongtimeandmust  
perform a vi tal  rol e as a safet y devi ce.   For t hi s 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 inspection since this is an instrument for
security and safety.  If this detector head founds defective, contact our nearest agent or
RikenKeikisoon.  


６− １．I n s pe c t i o n  f r e qu e n c y  a n d  i t e ms 
Theinspectionincludesadailyinspection which a person in charge ofcontrol andoperationof
the gas detection instrument performs inspection before work once a day, and a monthly
inspection carried out once a month, and periodical inspectionsconductedbytheservice
personnel  desi gnated by manufacturer.  The i nspect i on i tems 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 J apan sets forth that the unit
must  i s s ue  a n a l a rm dur i ng t he  c i r c ui t  i ns pe c t i on r e l a t e d t o al arm 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 regul ar mai nt enance,  adj ust ment 
andoverhaul etc includingthegassensitivityadjustment (gas calibration). 
Forthedetailofmaintenancecontract,contactournearestagent or Riken Keiki.  


・T h i s  i s  a  s a f e t y  i n s t r u m e n t  a n d  t h e  i n s p e c t i o n  e v e r y  6  m o n t h s  ormoreis
mandat ory  t o e nsure  t he s afet y .   I f t he  uni t  i s  use d by c ont i nuously
wi thout  i nspecti on,  the sensor sensi t i vi t y may change, resul t i ng i n fai l ure
of correct detection.












WA R N I N G 
！
*NOTE
・B e  s u r e  t o  i n f o r m  s e c t i o n s  c o ncerned beforehand when performi ng 
alarmtestorgascalibration.Fortheequipmentconnectedwithoutput 
signalfromindicator/alarmunit,performthemafterdisconnectingthe 
output si gnal.
・S p e c i a l  t r a i n e d  e n g i n e e r  f o r  g a s  d e t e c t i o n  i n s t r u m e n t  c a n  p e r f orm
mai nt e nanc e  wo r k a nd i ns pe c t i o n accurately and effici ently. Then, it is
recommendedtocontactourauthorizedagentformaintenance and
inspection.



14
６− ２．C a l i br a t i o n 

Performgascalibrationatnewinstallation,6monthsinspectionandsensorreplacement.    

６−２−１．Requiredkitandtoolsforcalibration

 Preparefollowingjigsandtoolstoperformzeroandspanadjustments.
・Calibrationadapter
・Calibrationgas(standardgasforzeroandspan)
・Gassamplingbagforcalibrationgas
・Suctionpumptoleadcalibrationgas
・Flowmeter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.
②Connectcalibrationadopter,flowmeter （withflowcontrolvalve） a n d  s u c t i o n  p u m p  t o 
thedetectorhead.Turnonthepumpandadjustthereadingofflowmeterto
1.0± 0. 3L/ mi n.  
③ConnectgassamplingbagforcalibrationtotheINsideofthepump. 
④After reading by indicator/ alarm unit gets stable, adjust the reading to zero with
respectivepotentiometerofindicator/alarmunit.
⑤Stop the supply of zero gas, disconnect calibration adapter andconfirmthatthe
oxygen reading returns to 20.9vol %.  

６−２−３．Performingaspanadjustment

①Pack the span gas (fresh air for oxygen deficiency alarm instrume nt  and t h e i r 
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. 
②Connectcalibrationadopter,flowmeter （withflowcontrolvalve） a n d  s u c t i o n  p u m p  t o 
thedetectorhead.Turnonthepumpandadjustthereadingofflowmeterto 
1.0± 0. 3L/ mi n.  
③ConnectgassamplingbagforcalibrationtotheINsideofthepump. 
④After reading by indicator/ alarm unit gets stable, adjust the reading to the span gas
concentrationwithrespectivepotentiometerofindicator/alarmunit.
⑤Stop the supply of span gas, disconnect calibration adapter andconfirmthatthe
oxygen reading i s 20.9vol  % (compl etion of span calibration). 

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15
６− ３． R e pl a c i n g t h e  s e n s o r  

６− ３− １． R e pl a c e me n t  f r e q u e n c y  o f  t h e  s e n s o r 

Tomaintainthereliabilityofthemeasurement,itisrecommendabletoreplacethesensor
peri odi cal l y.   Our oxygen sensor has an enough l i fe span.   However, the actual life is
dependi ng on t he operat i ng condi ti ons.   Then,  repl ace the sensor once a year as the
tentativedeadlineforthereplacementcycle.

６− ３− ２． R e pl a c i n g t h e  s e n s o r 

①Verify that the indicator/ alarm unit is off. If the sensor is disconnected,theindicator/alarmunit
issuesanalarm.
②Turnalockofdetectorhead and open the front  door. 
③Loosentwoscrewsatthetopofterminalstripanddisconnectedtwolead(blackandwhite)wires.
④Pushthesensorupwordfromthebottomofsensorandpulloutitfromtheholder.
⑤Insertnewsensorintotheholderandpushthesensoruntilitcomestotheend. 
⑥Connectblackandwhitesensorleadwirestotheterminalstrip.  Connectwhitewiretopositive
(+)terminalandblackwiretonegative(- )terminalrespectively.
⑦Closethefrontdoorofthedetectorheadandfastenalock.   






６− ３． R e pl a c i n g t h e  s e n s o r  … … … … … … … … … … … … … … … … … … … … … 
６− ３− １． R e qu i r e d ki t  a n d t o o l s  f o r  c a l i br a t i o n… … … … … … … … … … …  32
６− ３− ２． P e r f o r mi n g a  z e r o  a dj u s t me n t  … … … … … … … … … … … … … …  34
６−４． Storageortreatmentwhennotinuseforalongperiod…………………
６− ５． L i s t  o f  r e c o mme n da bl e  s pa r e partsforregularreplacement …………… 

６− ３− ２． P e r f o r mi n g a  z e r o  a dj u s t me n t  … … … … … … … … … … … … … …  34
６−４． Storageortreatmentwhennotinuseforalongperiod…………………
６− ５． L i s t  o f  r e c o mme n da bl e  s pa r e partsforregularreplacement …………… 

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
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




Blackleadwire Wh i t e  l e a d wi r e 
Terminalstrip
Cable
Sensor
Sensorholder


・ B e  s u r e  t o  c a r r y  o u t  g a s  c a l i b r a t i o n  a f t e r  s e n s o r  r e p l a c e m e n t .  If not, correct gas
det ecti on may not  be performed.   
CAUTION
！
Negati ve si de cable core
Positivesidecablecore



16
６− ４． S t o r a ge  o r  t r e a t me n t  wh e n  n o t  i n u s e  f o r  a  l o n g pe r i o d

 (1)Sensor
 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lowertheconsumption of sensor.

・Environmentoftemperature(5〜 10℃ )
・Environmentoflowoxygencontent
(Putasensorintothecontainerandsealoff the container.) 

(2)Detectorhead
Storethisdetectorheadunderthefollowingenvironmentalcondition.

・Temperature：0℃〜40℃ 
・Humidity:30%RH〜 85%RH
・Environmentalcondition:Environmentwheregas,solvent,vaporandsoonarenot
existing.








６− ５． Listofrecommendablespareparts for regular replacement 

No.  Name of parts I nspecti on frequency Replacementinterval Qʼ ty/ unit
1 Sensor hol der At  sensor replacement Atsensorreplacement 1

















・B e f o r e  r e - s t a r t  o f  o p e r a t i o n  ,  b esuretoperformgascalibration. 
・C o n t a c t  o u r  a u t h o r i z e d  a g e n t  o r  R i k e n  K e i k i  f o r  r e - a d j u s t m e n t  includinggascalibration, 
replacementofparts,etc.
CAUTION
！
*NOTE
Thereplacementintervalwillchangedependingonoperatingcondi ti on and i t  does not mean
theguaranteeperiod. 
Replacementintervalchangesaccordingtotheresultofregularinspection.



17


 ７− １． R e s po n di n g t o  t r o u bl e  a l a r m 
Ifthisdetectorfoundsdefective,contactourauthorizedagent or Ri ken Keiki.

７− ２． B e f o r e  i t  i s  t h o u gh t  t o  be  a  t r o u bl e 


・Check the wirings around the rel ated i nstruments as well as thisdetectorhead.

Itmaybecausedbyimproperoperation. 
・R e - c h e c k  t h e  d e t e c t i o n  s y s t e m  a n d  c o n t a c t  o u r  a u t h o r i z e d  a g e n t orRikenKeiki.


Galvaniccell

Galvaniccelltypeoxygensensorthatproduces a current proporti onal to the oxygen
ｃontenｔpermeatedthroughthemembrane.Referto“10.DETECTIONPRINCIPLE” 
fordetails.  
.


Safetyretainerforexplosionprot ect i on by l i mi t i ng t he energyofelectriccurrentwithin
anon-ignitionlevel.

CVVS

Thisisakindofconnecti ng cable between indi cator/ alarm uni t 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 uni t to match
thecalibrationgasconcentration. 
７． ME A S U R E S  A T  A B N O R MA L  C A S E 
Itmaybecausedbycabledisconnection, short ci rcuit,  etc. 
８．D E F I N I T I O N O F  T E R MS 
Zenerbarrier



18

９− １． S t a n da r d s pe c i f i c a t i o n s  
Model  ： G D- F 3A- 1
Detectionprinciple ： Galvaniccell method
Targetgas ： Oxygeninair
Samplingmethod ： Diffusionsampling
Signaltransmission ： Sensoroutput di rect transmi ssion
Transmissiondistance ： Max600mwithCVVS1.25sq,2Ccable
(betweenindicator/alarmunitanddetectorhead)
Appl icable zener barrier ： MTL761Pac
Cableentry ： Cablegland(ApplicablecableO.D.: φ8〜φ 11mm)
Operatingtemperature ： -10〜40℃
Operatinghumidity ： Below90％RH(Non-condensing)
Structure ： Wallmounting/2B(50A)polemounting
Kind of explosion proof ： I ntrinsical ly safe (when zener barri erisused)
Explosionproofclass ： ExiaⅡCT4X(whenzenerbarrierisused)
Outerdimensionｓ ： Appｒox175(H)× 140(W)× 86(D)mm
We i gh t  ： A ppｒo x  1. 4k g
Paintingcolor ： MunselNo.2.5Y9/2halftone

９− ２． S t a n da r d a c c e s s o r i e s 

・Operatinginstructionbook

９− ３． O pt i o n a l  a c c e s s o r i e s 

・U-bolt(fornominaldiameter2B)
・Calibrationadopter
・Zenerbarrier(MTL761Pac）
９．P R O D UC T  S P E C I F I C A T I O N S 