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TRANSCRIPT
CONTENTS
1. DESCRİPTİON OF THE ORGANİZATİON
1.1.Name of the Organization..………………………………………………….……..3
1.2.Location of the Organization..………………………………………………….….3
1.3.Number of Tecnical Staff………………………………………….……………….3
1.4.Brief history of the organization..………………………………………………….4
2.INTRODUCTİON……….…………………………………………………...………4
3.METROLOGY AND CALIBRATION…………………………………………….5
3 .1 De f in i t i on s o f s tand ard s o f meas ur emen t …………………………5
3.2 Base units……………………………………………………………………… 6
4 MEASUREMENT OF LENGTH………………………………………………......7
4.1 Gageblock
4.2 Calipers
4.3 Micrometer Calibration…………………………………………………………..9
4.4 Dimensional
5. MASS AND WEİGHT CALİBRATİON………………………………………….10
5.1 Certified Calibration Weights
6 Volume Measurements………………………………………………………….… 12
7 Pressure Measurements…………………………………………………….…… 13
8 Temperature Measurement……………………………………………….……….14
9 Electrical Metrology (DCLF) …………………………………………….………..16
10 TURKISH ACCREDITATION AGENCY………………………………………20
10.1 What is Accreditation?
10.2Purpose of Establishment
10.3Calibration Laboratories Certification
1
11. UME…………………………………………………………………………….22
11.2 OBJECTIVES of UME ……………………………………………………..23
12.CONCLUSION…………………………………………………………………..24
13. DEFİNİTİONS………………………………………………………………….24
14 APPENDİX……………………………………………………………………..25
1 .1 NA ME O F OR GA N IZA TI ON
Öl çme Kon t ro l S i s t em le r i Ka l ib r a s yon La bo ra tuva r C i haz l a r ı
S anay i V e T ica r e t L t d . Ş t i .
1 .2 LOC ATI ON OF OR GA NI ZA TIO N
Ga z ia n t ep Te ms i l c i l i ğ i
Ye d i t e pe M ah . 82 . S ok . E l i f Ap t . A l t ı N o : 14 / A
Ş ah inbey / Ga z i an t ep
Te l /F aks : + 90 342 360 80 91
2
Cep : + 90 531 368 04 31
gaz i an t ep@ ka l ib r a s yon .ne t
1 .3 NU MBER OF TECN İ CA L S TAF F
-Num ber o f pe r s ons emp l oyed :3
-Num ber o f eng i nee r s emp l oyed :1
-Ma in s phe re o f ac t i v i t y
3
1 . 4 BRI EF H IS TO RY OF THE OR GA N IZA TI ON
S ince i t s f ounda t i on in 1999 , O M EG A, ma nufac tu r e s ,
d i s t r i bu t e s , r epa i r s and c a l i b r a t e s h igh qua l i t y t e s t a nd ca l i b r a t i on
equ ipm en t fo r t he i ndus t ry and l a bo ra to r i a . S u i t ab l e fo r bo t h be nch - top
and f i e ld ca l i b r a t i on app l i c a t i ons , OM EG A 's r ange o f p r e s s u re , e l e c t r i c
and e l ec t ron i c , t e mpera l -humud i t y , d ime ns i ona l - l i nea r , m as s , p r e s s u re ,
g l a s s ma t e r i a l s – vo l ume , P H .
Om ega Ca l i b r a t i on La bo ra to ry has bee n ac c r ed i t ed by the T URK A K
Ac c red i t a t i on Counc i l ( ISO / IE C 17025) a t 2011 . I n 1998 O M EG A-
OM K A ga ined i t s ISO 9001 :2000 c e r t i f i c a t i on by A NS I A S Q N a t i ona l
Ac red i t a t i on Boa rd wi th A mer i can S ys t em Reg i s t a r , w h ic h cove r s a l l
a s pec t s o f com pany ope ra t i ons . Eac h m ember o f t he O M EG A te am i s
comm i t t ed t o t he pu r s u i t o f qua l i t y a nd cus tom er sa t i s f ac t i on fo r bo th
p roduc t s and s e rv i ce .
2 IN TR OD UC TI ON
I d id my s umm er p r ac t i ce a t Om ega -O mka Ca l ib r a t i on Com pany . I
l e a rn t ha t c a l i b r a t i on in s t rume n t and how i c a n u se t he s e i n s t rum en t s . I
a l s o l e a rn t ha t m eas u reme n t t oo l s no t a l wa ys show us exac t va lue o f t he
unknown va lues .
4
We c a l ib r a t e ou r i n s t rumen t wh i l e i t ’ s ou t f o r c a l i b r a t i on . I n
p r ac t i ce , c a l i b r a t i on inc lude s c o r r ec t i on . P u rpose o f c a l i b r a t i on i s t o
ens u re r ead i ngs f rom an in s t rum en t a r e cons i s t en t w i th o the r
i n s t rume n t s and to de t e rmine the ac cu racy o f t he i n s t rumen t i . e . t ha t i t
c an be t r u s t ed fo r i t s obs e rved / d i sp l ayed mea su re d va l ue . U s ua l l y
cus tome r s end an i n s t rumen t fo r ca l i b r a t i on , w e au tho r i z e r e pa i r t o
b r ing the i n s t rume n t back i n to ca l i b r a t i on i f i t w as “ou t o f c a l ” .W e s en t
a r epo r t show ing how f a r ou t o f c a l i b r a t i on the i n s t rumen t a nd how f a r
ou t i t i s a f t e r .
3 METR OLOG Y A N D C A LIBR A TIO N
M etro logy i s t he s c i enc e o f mea su re men t . M e t ro l ogy inc ludes a l l
t heo re t i c a l and p r a c t i ca l a s pec t s o f m eas u reme n t . T he dev ice w i th t he
known o r a s s igne d co r r ec t nes s i s c a l l e d t he s t a nda rd .
Cal ib ra t ion :The se t o f ope ra t i ons wh i ch e s t a b l i s h , unde r s pec i f i ed
cond i t i ons , t he r e l a t i onsh i p be tw een va lues i nd i ca t ed by a me as u r ing
in s t rume n t o r me as u r ing s y s t em , o r va lues r ep re s en t e d by a m a te r i a l
mea su re , and the c o r r e s pond ing know n va lues o f a m eas u rand .
3 .1 De f in i t i on s o f s tand ard s o f meas ur emen t
In ter nat i on a l s tand ard : A s t anda rd r e cogn ize d by an in t e rna t i ona l
ag ree men t t o se rve i n t e rna t i ona l l y a s t he ba s i s f o r a s s ign ing va lues t o
o the r s t a nda rds o f t he quan t i t y c once rned .
5
Nat i on a l s tan d ard : A s t anda rd r ecogn i zed by a na t i ona l dec i s i on t o
se rve , i n a coun t ry , a s t he ba s i s f o r a s s ign i ng va lues t o o the r s t anda rds
o f t he s am e quan t i t y .
Pr i mary s tan d ard : A s t anda rd t ha t i s de s igna t ed o r wi de ly
acknow le dged a s hav ing t he h ighes t m e t ro l og i ca l qua l i t i e s a nd whos e
va lue i s a cce p ted w i t hou t r e f e r e nce t o o t he r s t anda rds o f t he sa me
quan t i t y .
S econ d ary s tan d ard : A s t anda rd w hos e va lue i s a s s i gned by
compa r i s on wi th a p r i mary s t anda rd o f t he s ame quan t i t y .
Re feren ce s tan dar d : A s t anda rd , gene ra l l y hav ing the h ighes t
me t ro log i c a l qua l i t y a va i l ab l e a t a g i ven loca t ion o r i n a g ive n
o rgan iz a t i on , f r om w h ich the mea su rem en t s t a ken the r e a r e de r i ved .
Work in g s tand ard : A s t anda rd t ha t i s u s ed rou t i ne ly t o ca l i b r a t e o r
chec k ma te r i a l meas u re s , me as u r ing in s t rum en t s o r r e f e r e nce ma te r i a l s .
Th e fo l low in g u n i t s sh ou ld b e u se d for meteoro l og ica l
ob ser va t ion s :
( a ) A tmos phe r i c p r e s su re , p , i n hec topas ca l s ( hP a )
(b ) Tem pera t u r e , t , i n de g rees Ce l s iu s ( °C) o r T i n ke lv i n (K) ;
( c ) Wind spe ed , i n bo th s u r f ace and uppe r - a i r obs e rva t i ons , i n
me t r e s pe r s econd (m/ s ) ;
( d ) W ind d i r ec t i on i n deg re es c l ockw is e f rom no r t h o r on the s ca l e
0–36 , whe re 36 i s t he wi nd f rom the no r t h and 09 the wi nd f rom the ea s t
( ° ) ;
6
( e ) Re l a t i ve humid i ty , U , i n pe r c en t (%) ;
( f ) P r ec ip i t a t i on ( t o t a l am oun t ) i n m i l l ime t r e s (mm ) o r k i l og ra ms
pe r m^ 2(kg /m^ 2) ;
(g ) P rec ip i t a t i on in t ens i t y , R i , i n mi l l i me t r e s pe r hou r (mm/ h ) o r
k i l og ra ms pe r m–2 pe r sec ond (kg /m^ 2 . s ) ;
( h ) S now w a te r equ iva l en t i n k i l og ra ms pe r m–2 ( kg m –2) ;
( i ) Eva po ra t i on in mi l l i me t r e s (m m) ;
( j ) V i s ib i l i t y i n me t r e s (m) ;
( k ) I r r a d i ance i n w a t t s pe r m ^2 and r a d i an t expos u re i n j ou l e s pe r
m^2(W /m^ 2 , J / m^2) ;
( l ) D ura t i on o f suns h ine i n hou r s (h ) ;
(m) C loud he igh t i n me t r e s (m) ;
( n ) C loud am oun t i n ok t a s ;
( o ) Ge opo ten t i a l , u sed i n uppe r - a i r obse rva t ions , i n s t a nda rd
geopo te n t i a l me t r e s (m’ ) .
3 . 2 Base Un i t s
1 Mete r
1983 Oc tobe r 21 – T he 17 th CG P M de f ines t he m e t r e a s e qua l t o t he
l eng t h o f t he pa th t r ave l l e d by l i gh t i n vacuum du r i ng a t i me in t e rva l o f
1 ⁄ 299 ,792 ,458 o f a s econd . [13 ]
1 S econ d
7
S ince 1967 t he s ec ond has been de f ined a s t he du ra t i on o f
9 ,192 ,631 ,770 pe r iods o f t he r ad i a t i on co r r e s pond ing to t he t r ans i t i on
be tw ee n the tw o hype r f ine l e ve l s o f t he g round s t a t e o f t he c ae s ium 133
a tom .
1 Amp er
t he cons t an t cu r r e n t t ha t w i l l p roduce an a t t r ac t i ve fo r ce o f 2 × 10–
7 ne wt on pe r me t r e o f l e ng th be tw een tw o s t r a i gh t , pa r a l l e l conduc t o r s
o f i n f in i t e l eng th a nd neg l ig i b l e c i r cu l a r c ro s s s ec t i on p l aced one me t r e
apa r t i n a vac uum.
1 Ki l ogram
T he k i log ram o r k i l og ra mme ( s ymbo l : kg ) i s t he ba s e un i t o f mas s
i n t he In t e rna t iona l S ys t em o f Un i t s . The k i log ram i s de f ined a s be i ng
equa l t o t he mas s o f t he In t e r na t i ona l Pr o to t ype K i logr am (F ig3 )
The K e l v in s ca l e i s an abs o lu t e , t he rm odynami c t em pera t u r e s ca l e
u s i ng a s i t s nu l l po in t a b so l u t e ze ro , t he t empera tu r e a t w h ich a l l
t he rm a l m o t ion c eas e s i n t he c l a s s i ca l de s c r ip t i on o f t he rmodynam ics .
The ke lv in i s de f ined a s t he f r ac t i on 1 ⁄ 273 .16 o f t he t he rmodyna mic
t em pera t u r e o f t he t r i p l e po in t o f w a t e r ( 273 .16 K (0 .01 °C ; 32 .02 °F ) ) .
1 Kan d e la
The cande l a i s t he l uminous i n t ens i t y , i n a g iven d i r ec t i on , o f a
sou rc e t ha t emi t s monoch rom a t i c r ad i a t i on o f f r e quency 540× 10^12
he r t z and tha t ha s a r ad i an t i n t ens i t y i n t ha t d i r ec t i on o f 1 ⁄ 683 w a t t pe r
s t e r ad i an .
1 Mol
De f ined a s an a moun t o f a subs t a nce t ha t con t a in s a s many
e l e men t a ry e n t i t i e s ( e . g . , a t oms , mo l ecu l e s , i ons , e l ec t rons ) a s t he r e a r e
a tom s in 12 g r am s o f pu re ca rbon -12 T hus , by de f i n i t i on , one mo l e o f
pu re 12C has a m ass o f exa c t l y 12 g .
8
4 MEA SU R EMEN T OF LEN GTH AN D DI MEN S IO N
We o f t en exp re s s d i s t anc e i n un i t s onc e de r i ved f rom the
d ime ns i ons o f hum an body pa r t s . T he inch i s r ough l y t he w id t h o f a
t humb; t he foo t un i t i s ba s ed on the s i ze o f a r e a l f oo t .The t r oub l e wi th
a l l o f t he s e i s t ha t humans c ome in a va r i e ty o f s hape s and s i ze s .Thus
t he i n t roduc t ion o f s t anda rd l eng th un i t s c am e the ru ler , t h e tap e
meas ur e , t h e su rve yor ’ s ch a in , a nd a who l e hos t o f s i mp le me asu r i ng
dev ic e s wi th mi l l i me te r p r ec i s i on .
4 .1 Gageb loc k
The un i t o f l eng th i n many indus t r i e s i s m a in t a ine d and
d i s se mina t ed by gauge b l ocks . The h ighe s t a c cu racy ca l i b r a t i ons o f
gauge b l ocks a r e done by l a s e r i n t e r e rome t ry w h ich a l l ow s t he t r a ns f e r
o f t he un i t o f l e ng th t o a gauge p i e ce . P r i mary s t anda rds l abo ra t o r i e s
ma i n t a i n ma s t e r s e t s o f E ng l i s h gauge b locks a nd me t r i c gauge b loc ks
wh i ch a r e ca l i b r a t e d i n t h i s m anne r . A typ i c a l c a l i b r a t i on i nvo lves a s e t
o f 81 gauge b l ocks wh i ch a r e c ompared one -by -one w i th m as t e r gauge s
o f t he s am e nom ina l s i ze . Ea ch ga uge b l ock cons i s t s o f a b l ock o f me t a l
o r c e r a mic w i t h tw o oppos i ng f ace s g round p rec i s e ly f l a t and pa ra l l e l , a
p r ec i se d i s t ance apa r t . S t anda rd g r ade b locks a r e m ade o f a ha rdened
s t ee l a l l oy , wh i l e ca l i b r a t i on g r ade b locks a r e o f t en ma de o f t ungs t en
ca rb i de o r ch romi um ca rb ide bec aus e i t i s ha rde r and we a r s l e s s . Gauge
b locks a r e ca l i b r a t e d t o be accu ra t e a t 68 °F (20 °C) and s hou ld be kep t
a t t h i s t em pera tu r e whe n t ak i ng meas u rem en t s and s hou ld be ke p t a t t h i s
t em pera t u r e whe n t ak i ng meas u rem en t s .
The un i t o f l eng th i n many indus t r i e s i s m a in t a ine d and
d i s se mina t ed by gau ge b lock s . F ig1 . The h i ghes t a c cu racy c a l i b r a t i ons
o f ga uge b l ocks a r e done by l a s e r i n t e r e rom e t ry w h ich a l l ows t he
t r ans f e r o f t he un i t o f l e ng th t o a gauge p i e ce .G age b locks a r e u sed to
9
ca l ib r a t e o the r , l e s s ba s i c mea su r i ng in s t rume n t s , i nc lud i ng the one tha t
c an be found in v i r t ua l ly e ve ry eng i nee r ’ s t oo lbox : th e ca l i pe r (F ig2 )
4 . 2 Ca l ip ers
The s u rp r i s ing p r e c i s ion o f ea r ly ca l i pe r s s t em s f rom the i nven t ion
o f a s even t een th -c en tu ry F re nch s c i en t i s t , P i e r r e V e rn i e r , w h ich
a l l owe d fo r r eadou t s w i th i n 1=256 a nd on l a t e r mode l s 1= 1000 o f an
i nch .
4 .2 .1 CA LI BRA TI ON OF V ER NI ER CA LLI PER GA UG ES
OBJEC TIV E:
The ob j ec t ive o f t h i s S O P i s t o ens u re t he Ve rn i e r Ca l ipe r g i ves
acc u ra t e a nd r ep roduc ib l e da t a .
RES P ON SI BI LITY :
Exec u t ive – Qua l i t y Con t ro l D epa r t men t sha l l be :
Res pons i b l e fo r e nsu r i ng t i me l y ca l i b r a t i on o f V e rn i e r c a l i pe r and
d i a l t h i c knes s gauge t e s t e r
PR OC EDU R E
1.Op era t i on
Take ou t V e rn i e r Ca l ipe r f rom the mou lded p l a s t i c box . .
C lea n i t w i t h t i s s ue pape r .
P re s [ O N ] key & e nsu re t he d i s p l a y show ing 0 .00 m m.
Ho l d the s am p le be t we en the tw o f inge r s .
Ad j us t Ve rn i e r w i t h i t s move b le pa r t ove r t he sam p le t o check t he
r equ i r e d pa r ame te r .
No t e dow n the r e ad ing s hown on t he d i s p l a y .
Af t e r u s e p r e s s t he [ O F F ] ke y o f t he i n s t rum en t .
C lea n the i n s t rumen t a f t e r u s e and ke ep in t he mou l ded box .
10
2 . Ca l ib ra t ion
Take the s t anda rd gauge p l a t e s o f t h i cknes s
0 .5 ,1 .01 ,1 .49 ,5 .0 ,50 ,100 mm a nd mea su re t he t h i cknes s o f each p l a t e by
u s i ng ve rn i e r c a l i pe r and c on f i rm the t h i c knes s d i s p l aye d i s ma t ched
wi th s t anda rd .
3 . Ca l ib ra t ion F req u en cy : Mont h ly .
4 .3 Mic rometer Ca l ib ra t ion
4 .3 .1 .S cop e
The c a l i b r a t i on p roc edu re i s app l i ca b l e t o ca l i b r a t i on o f ex t e rna l
mic rome t e r 0 -25 mm , 25 -50 mm, 50 -75 m m and 75 -100 mm .
The P roce du re i s app l i cab l e t o m ic rome te r s ba s ed on s c r ew gauge
p r inc i p l e fo r m eas u reme n t o f ex t e rna l d i mens ions o f l e a s t coun t .
4 .3 .2 .Pu rp os e
To ens u re t ha t t he mic rome t e r p roduces cons i s t e n t ly r epe a t e d spec i f i c
mea su re men t r e su l t s and a s s oc i a t ed me asu re men t unce r t a in ty .
4 .3 .3 Ca l ib ra t ion P roced u re
1 . Pr i nc ip l e
Ac curacy i s de t e rm ined by com par i s on w i th c a l i b r a t ed s l i p gauges and
wi r e s . F l a tne ss and pa ra l l e l i s m o f a nv i l s i s de t e rmine d by ca l i b r a t e d
op t i c a l f l a t s ( f l a t ne s s l / 10 ) .
2 .Fo l l owi n g t e s t s are recomme nd ed to b e p er for med
1. Visual inspection
11
2 . Ratc he t f unc t ion ing
3 . Zero e r ro r
4 . Repea tab i l i t y
5 . F la tne ss and pa ra l l e l i s m o f a nv i l s 6 . Ac curacy o f s ca l e
Af t e r v i s ua l i n s pec t i on the m ic rom e te r unde r ca l i b r a t i on i s c l a mped i n
mic rome t e r c l a mp ing s t a nd to p r even t t em pera t u r e change s on ac coun t
o f hand l i ng o f mic rome t e r du r ing ca l i b r a t i on .
The m ic rom e te r a nv i l , s l i p gauges (mi ke -chec k se t ) , s t anda rd w i r e s and
op t i c a l f l a t a r e deg reas ed , c l eane d wi th benz ene and l i n t f r e e c lo t h and
l e f t on t he s u r f ace p l a t e f o r abou t t wo hou r s s o t ha t t he t empera tu r e o f
a l l t he s e i s nea r ly t he sa me .
3 .S up p or t Eq u ip men t
The support equipments required for calibration are given in table 2.
S up p or t eq u ip men t S pe c i f i c a t ion
Mi crome te r
c l a mp ing s t a nd
The rm omet e r 10 -30 °C Lea s t coun t
0 .1 °C o r be t t e r
Gra n i t e su r f a ce
p l a t e (G rade -1 )
Approp r i a t e s i ze
C lea n ing M a te r i a l s L in t f r ee c lo th , w h i t e
pe t ro l / ac e tone
12
4 .En v iron men ta l C on di t ion s
The l abo ra t o ry has a con t ro l l ed / uncon t ro l l ed env i ronmen t g iven be l ow:
Tem pera t u r e ( con t ro l l ed ) : 20 ± 2 °C
Re la t i ve Hum id i t y (uncon t ro l l ed ) : 50 ± 10%
5 . MA SS A N D WEİ GH T CA Lİ BRA Tİ ON
The un i t o f l eng th i n many indus t r i e s i s m a in t a ine d and
d i s se mina t ed by gauge b l ocks . The h ighe s t a c cu racy ca l i b r a t i ons o f
gauge b l ocks a r e done by l a s e r i n t e r e rome t ry w h ich a l l ow s t he t r a ns f e r
o f t he un i t o f l e ng th t o a gauge p i e ce . P r i mary s t anda rds l abo ra t o r i e s
ma i n t a i n ma s t e r s e t s o f E ng l i s h gauge b locks a nd me t r i c gauge b loc ks
wh i ch a r e ca l i b r a t e d i n t h i s m anne r . A typ i c a l c a l i b r a t i on i nvo lves a s e t
o f 81 gauge b l ocks wh i ch a r e c ompared one -by -one w i th m as t e r gauge s
o f t he s am e nom ina l s i ze . Eac h gauge b loc k cons i s t s o f a b lock o f m e ta l
o r c e r a mic w i t h tw o oppos i ng f ace s g round p rec i s e ly f l a t and pa ra l l e l , a
p r ec i se d i s t ance apa r t . S t anda rd g r ade b locks a r e m ade o f a ha rdened
s t ee l a l l oy , wh i l e ca l i b r a t i on g r ade b locks a r e o f t en ma de o f t ungs t en
ca rb i de o r ch romi um ca rb ide bec aus e i t i s ha rde r and w ea r s l e s s . Ga uge
b locks a r e ca l i b r a t e d t o be accu ra t e a t 68 °F (20 °C) and s hou ld be kep t
a t t h i s t em pera tu r e w hen t ak i ng me as u remen t s and shou l d be kep t a t
t h i s t e mpera tu r e w hen t a k ing me asu re men t s .
Ne a r - acc u ra t e ma ss m eas u rem en t s r e qu i r e a s eque nce o f de s igns
t ha t r e l a t e t he mas s e s o f i nd iv i dua l w e igh t s t o a r e f e r e nce k i log ram(s )
s t anda rd ( J aege r & D av i s ) . W e igh t s gene ra l l y come in s e t s , a nd an
13
en t i r e s e t m ay r equ i r e se ve ra l s e r i e s t o ca l i b r a t e a l l t he w e i gh t s i n t he
se t .
F o r Exa mple , A 5 ,3 ,2 ,1 w e i gh t se t w ou ld have the fo l l owi ng
we igh t s :
1000 g 500g , 300g , 200g , 100g 50g , 30g 20g , 10g 5g , 3g , 2g , 1g
0 .5g , 0 . 3g , 0 . 2g , 0 . 1g
5 . 1 Ce r t i f i ed Ca l ib ra t ion Wei ght s
Mas s M eas ur emen ts
The un i t o f ma ss i s t he k i l og ram wh i ch i s de f i ned a s t he m as s o f t he
In t e rna t iona l P ro to t ype Ki log ram ma in t a i ned a t t he In t e rna t iona l Bu re au
o f We i gh t s and M eas u re s (B IPM ) in F ranc e . A copy o f t he P ro to t ype ,
no . 75 , be ing o f t he s am e fo rm a nd ma te r i a l , i s be i ng kep t by th i s
Labo ra to ry a s t he r e f e r ence mea su rem en t s t a nda rd o f mas s fo r Hong
Kong a nd fo r t he d i s s em ina t i on o f t he un i t o f ma ss .
The Labo ra to ry can p rov ide ca l i b r a t i on s e rv i c e s fo r s t anda rd
we igh t s o f a c cu racy c l a s s E 2 a nd low er i n t he r ange f rom 1 mg to 10 kg ,
and s t anda rd we i gh t s o f a cc u racy c l a s s F 1 and l ower f rom 20 kg to 50
kg . T he c l a s s i f i c a t i on o f w e i gh t s depe nds on t he i r max i mum pe rmi ss ib l e
mea su re men t e r ro r s ( r e f e r t o t he fo l l ow ing t ab l e ) , sha pe , ma t e r i a l ,
cons t ruc t ion a nd s u r f ace f i n i sh , a s de sc r ibed in t he In t e rna t iona l
Recom menda t ion R111 - (We igh t s o f a ccu rac y c l a s se s E1 , E2 , F 1 , F2 ,
M1 , M 2 , M 3 ) o f t he In t e rna t iona l O rgan i za t ion o f Lega l M e t ro l ogy
(OIM L) .
The s ubmi t t e d we igh t s s hou ld be i n a c l e an cond i t i on and hous ed i n
a s u i t a b l e con t a ine r o r con ta i ne r s .
14
Dur i ng c a l i b r a t i on t e s t w e igh t s a r e compa red w i t h app rop r i a t e
mea su re men t s t a nda rds . As w e igh t s o f h i ghe r acc u racy c l a s s r equ i r e u s e
o f mea su re men t s t a nda rds o f h ighe r ac cu racy a nd more e l abo ra t e
ca l i b r a t i on p rocedu re s , c a l i b r a t i on c ha rge w i l l be h ighe r . The cus tom er s
a r e t he r e fo re u rge d to app l y fo r ca l i b r a t i on ac cu racy app rop r i a t e t o
t he i r u s ages ( see fo l l ow ing pa rag raph fo r r e f e r ence ) and spe c i f i c a t i ons
o f t he i r we igh t s . F o r exam ple , owi ng to t he i r b r i t t l e p rope r ty and
in f e r i o r r e s i s t ance t o w ea r and c o r ro s i on , c a s t i r on we i gh t s wi l l on l y be
u se d a s we igh t s o f a cc u racy c l a s s M 1 and l ower .
F o r ca l i b r a t i on o f we igh ing m ach ine s , no rm a l l y t he me as u remen t
unce r t a in t i e s o f t he w e i gh t s u se d wi l l be l e s s t han the r e so l u t ion o f t he
mac h ine t o be ca l i b r a t ed .
The Labo ra to ry has deve l oped a ve ry s imp l e a nd conc i s e gu i de l i ne
fo r ba l ance u s e r s t o s e l e c t a s u i t ab l e c l a s s o f w e igh t s f o r ba l anc e
ca l i b r a t i on :
Ca l c u l a t e n = c apac i ty / r e so l u t ion
When n = 10 000 o r s ma l l e r , u s e c l a s s M 1 w e igh t s (F ig 4 )
When n > 10 000 to 30 000 , u s e c l a s s F 2 w e igh t s
When n > 30 000 to 100 000 , u s e c l a s s F 1 w e igh t s
When n > 100 000 to 300 000 , u s e c l a s s E 2 we igh t s
When n > 300 000 o r above , u s e c l a s s E1 w e igh t s
A pa pe r de s c r ib i ng the w ay o f e s t ab l i s h ing t h i s gu ide l ine ha s bee n
pub l i s hed i n t he O IM L Bu l l e t i n , I s s ue J u ly 2009 .
The m eas u red va l ue fo r t he t e s t w e igh t wi l l be t he m ass o f a
hypo the t i ca l w e i gh t o f dens i t y 8000 kg /m3 wh i ch , a t 20 °C and i n a i r o f
dens i ty 1 .2 kg / m3 , w ou ld ba l ance t he t e s t we i gh t . The bas i s i s t aken by
conven t ion a nd ac co rds w i th O IML ( In t e rna t i ona l Orga n iza t ion o f Le ga l
Me t ro logy ) In t e rna t iona l D ocum en t D 28 .
15
The mea su re men t unce r t a in t y quo t ed w i l l no rma l l y r e l a t e t o t he
acc u racy c l a s s o f t he subm i t t ed we i gh t , suc h tha t t he meas u rem en t
unce r t a in t i e s wi l l be l e s s t han o r equa l t o 1 / 3 o f t he p r e sc r i bed
max i mum pe rmis s ib l e meas u rem en t e r ro r s .
6 . Vo l u me Meas u remen ts
The L abo ra t o ry de t e rm ines t he con ta i ned vo lum e ( capa c i t y ) o r t he
de l i ve r ed vo l ume o f a ve ss e l ( Fig5 ) . The c on ta i ned vo lume i s t he vo l ume
o f wa te r r e qu i r ed t o f i l l t he ve s s e l a t 20 °C , wh i l s t t he de l i ve r ed vo lum e
i s t he vo l ume o f w a t e r w h ic h ma y be pou red f rom t he vess e l a t 20 °C
unde r spec i f i e d cond i t i ons ( e . g . w i t h a f i xed d r a i nage t im e o f 30
se conds a f t e r c e s sa t i on o f m a in f l ow ) . The de l i ve r ed vo lum e i s a l wa ys
l e s s t han t he con ta ined vo l ume , due t o t he f i lm o f l i qu id l e f t on t he
wa l l s o f t he ve s se l a f t e r de l i ve ry . The d i f f e r ence be tw een t he con t a ined
and de l ive r ed vo l ume fo r g l a s sw are m ay be o f t he o rde r o f 0 .1% o f t he
capa c i ty fo r a 1 L f l a sk i nc r ea s ing t o 0 .25% fo r a 50 mL f l a s k , w hen
u s i ng wa te r .
The re a r e tw o me t hods emp l oyed by th i s Labo ra to ry fo r vo lum e t r i c
de t e rmina t ion . The g r av im e t r i c m e thod de t e rmine s t he mas s o f wa te r
e i t he r c on ta i ned o r de l i ve r ed f rom a t e s t m eas u re . F rom t he m eas u red
mas s , t he vo l ume ca n be de t e rmine d wi th a know le dge o f wa te r de ns i ty
and co r r e c t ions fo r a i r buoyancy and t he rma l expans ion o f t he ve s s e l .
The vo l ume t r i c m e thod r equ i r e s a mea su re men t s t anda rd ( ca l i b r a t ed )
vo lume t r i c meas u re . T he vo lum e o f t he t e s t vo lum e t r i c ve s se l i s
de t e rmine d f rom the num ber o f "dumps " o f t he meas u rem en t s t a nda rd
mea su re r equ i r ed t o f i l l t he t e s t mea su re . Norm a l l y g r av ime t r i c me t hod
wi l l be u se d fo r vo lume t r i c de t e rmina t ion a t t he ca pac i t y o f 20 L o r
be low , w h i l s t vo l ume t r i c m e thod w i l l be u s ed fo r me asu re men t s a bove
20 L .
The s ubmi t t e d ves se l s s hou ld be i n a c l ean c ond i t i on .
16
7 . Pre ss u re Me asu re men ts
The L abo ra t o ry i s equ ipped w i t h p r e s su re ba l anc es , p r e s s u re
con t ro l l e r s and p r ec i s ion qua r t z Bourdon p re s su re gauges t o p rov i de
p r e s su re ca l i b r a t i on se rv i ce s .
The Labo ra to ry can p rov ide o i l p r e s su re ca l i b r a t i on se rv i ce s i n t he
gauge m ode f rom 0 .5 M P a (5 ba r ) t o 140 M P a (1 ,400 ba r ) f o r p r e s s u re
gauges , t r ans duce r s a nd p r e s s u re t r ans mi t t e r s . T he Labo ra t o ry ca n a l so
p rov ide gas p r e ss u re ca l i b r a t i on s e rv i c e s i n bo th abs o lu t e and gauge
modes f rom 1 kP a (0 .01 ba r ) t o 7 M Pa (70 ba r ) . ( Fig 6 )
The s ubmi t t e d i n s t rume n t s hou ld be i n a c l e an cond i t i on .
F o r ga s p r e ss u re c a l i b r a t i on , t he p r e s s u re med i um w i l l be n i t r ogen .
Ca l i b r a t i on i s gene ra l l y pe r fo rmed by a pp ly ing p r e s su re s o f know n
va lue s t o t he un i t unde r t e s t i n s u f f i c i en t num ber o f s t eps (no rma l ly
abou t 7 ) d i s t r i bu t e d th roughou t i t s u s ab l e r ange , f r om low er t e s t va lue s
t o max i mum ca l ib r a t i on va lue , and t hen de c rea s ed backw ards t o i n i t i a l
t e s t va lue .
E le c t ron i c ba rome te r c an a l s o be c a l i b r a t ed by t h i s Labo ra t o ry ,
p rov ided tha t t he e l ec t ron i c ba rome te r ha s a connec t ion fo r i npu t
17
pre s su re . Ca l ib r a t i on i s pe r fo rm ed a t f i ve po i n t s f rom 800 hPa to 1100
hP a unde r bo th r i s i ng p r e s su re and f a l l i ng p r e s s u re cond i t i ons .
S phygmomanom ete r f o r b lood p r e s s su re m eas u rem en t ca n a l s o be
ca l i b r a t ed . Ca l i b r a t i on wi l l be pe r fo rmed by a pp ly ing know n p re s s u re s
t o t he sphygm omanom ete r unde r t e s t , and the r eby the
sphygm omanom ete r i s r equ i r ed t o have a p r e ss u re i n l e t f o r p r e s s u re
i npu t .
The p r e ss u re conne c t i ons o f t he s ubmi t t ed i n s t rum en t s s hou ld be a s
f o l l ow s :
8 . TEMPER A TUR E MEA S UR EMEN T
The S I un i t o f t he funda men t a l phys i ca l quan t i t y " t empera tu r e " , o r
more p r ec i se ly " t he rmodyna mic t e mpera t u r e " , i s t he ke l v in , de f ined a s
t he f r a c t i on 1 /273 .16 o f t he t he rmodyna mic t empe ra tu r e o f t he t r i p l e
po in t o f w a t e r .
N.
P .T .
B .
S .P .
A
.P . I .
Metr i
c
1 /
8 i n
1 /
8 i n
1 /
8 i n
M12
x 1 .5
1 /
4 i n
1 /
4 i n
1 /
4 i n
M20
x 1 .5
3 /
8 i n
3 /
8 i n
3 /
8 i n
1 /
2 i n
1 /
2 i n
1 /
2 i n
18
Beca use o f t he w ay ea r l i e r t empe ra tu r e s ca l e s we re de f i ned , i t
r ema ins com mon p rac t i ce t o exp re s s a t em pera tu r e i n t e rms o f i t s
d i f f e r e nce f rom 273 .15 K , t he i c e po in t . A the rm odynami c t e mpera t u r e ,
T , exp re s se d i n t h i s w ay i s known a s Ce l s iu s t e mpera tu r e , sym bo l t ,
d e f ine d by :
t ( i n °C) = T ( i n K) - 273 .15
The p r e c i s e me as u remen t o f t he rm odynami c t em pera t u r e s , f o r
exam ple wi th a ga s t he rm omet e r , i s ve ry d i f f i cu l t . P r a c t i ca l t em pera t u r e
sc a l e s we re t he r e fo re i n t roduced to m ake u se o f i n s t rume n t s s uch a s
p l a t i num r e s i s t ance t he rmom ete r s w h ich a r e much e a s i e r t o u se a nd g ive
much h i ghe r p r ec i s i on mea su re men t s .
The f i r s t I n t e rna t iona l T empera tu r e S ca l e w as adop t ed in 1927 ,
r ev i s ed in 1948 a s IPT S-48 , r ev i s ed aga i n i n 1968 a s IP TS -68 , a nd
aga i n more r ec en t l y i n 1990 a s ITS -90 . O f f i c i a l l y S CL adop t ed t he IT S -
90 f rom 1 J anua ry 1990 .
The L abo ra t o ry r ea l i se s t he ITS -90 by ma in t a i n ing the fo l l ow ing f i xed
po in t s t a nda rds a t :
T r ip l e po in t o f a rgon ( -189 .3442 °C) .
T r ip l e po in t o f merc u ry ( -38 .8344 °C) .
T r ip l e po in t o f wa te r ( 0 .0100 °C) .
Me l t i ng po in t o f ga l l i um (29 .7646 °C) .
F r eez i ng po in t o f i nd ium (156 .5985 °C) .
F r eez i ng po in t o f t i n (231 .928 °C) .
F r eez i ng po in t o f z inc (419 .527 °C) .
F r eez i ng po in t o f a lumi n ium (660 .323 °C) .
F r eez i ng po in t o f s i l ve r ( 961 .78 °C) .
In add i t i on to t he above f i xed po in t p r ima ry t em pera tu r e s t anda rds ,
t he Labo ra to ry poss e s se s s t anda rd p l a t i num r e s i s t anc e t he rmom ete r s and
s t anda rd t ype R the rm ocoup le s w h ic h a r e ca l i b r a t ed d i r e c t l y i n ITS -90 .
19
Apa r t f r om t he a bove f i xed po in t s , c a l i b r a t i on s e rv i ce cove r s t he
fu l l r ange f rom -80 °C to 1200 °C , and c a t e r s f o r a l mos t a l l p r ac t i ca l
t he rm omet e r s s uch a s l i qu id - in -g l a s s t he rm omete r s , d ig i t a l
t he rm omet e r s , t he rmoc oup le o r r e s i s t ance t he rmom ete r s , e t c .
8 .1 Th ermomete r Ca l ib ra t ion Me thod s
1 . Ic e Po i nt M eth od
F i l l an i n s u l a t ed con t a ine r , s uch a s a w ide mou th “ the rm os” bo t t l e
wi th a m ix tu r e o f po t ab l e c ru s hed i c e and w a te r .
• The con ta ine r mus t have c ru s hed i ce t h roughou t t o p rov ide an
env i ronm en t o f 32°F , s o you may ha ve to pac k more i c e i n t o t he
con ta ine r du r i ng the p roce ss .
• When t he mi x tu r e o f t he wa te r ha s s t ab i l i z ed a f t e r f ou r o r f i ve
minu t e s , i n se r t t he t he rmom ete r t o be ca l i b r a t e d t o t he app rop r i a t e
imm ers ion dep t h . ( no t e : f r om t i p o f t he rmom ete r t o t he d imp l e on s t em
i s t he s ens ing po r t i on )
• Be su re t o ho ld t he s t em o f t he i n s t rumen t aw ay f rom the bo t tom
and s i de s o f t he con ta i ne r ( p r e f e r ab l y one inch ) t o avo id e r ro r . Wa i t
un t i l t he t he rmom ete r s t a b i l i z e s be fo re a d ju s t i ng t he t he rm omet e r .
20
• I f you r t he rm omet e r i s no t a ccu ra t e wi th in + / - 2 °F o f 32°F . ,
ad ju s t t he t he rmomet e r ac co rd ing ly . T he i c e po in t me thod pe rmi t s
c a l i b r a t i on to w i t h in 0 .1 °F .
2 .Bo i l i n g Po in t Meth od
• Af t e r t he wa te r i n t he con ta i ne r ha s r eac hed a com ple t e “ ro l l i ng”
bo i l , i n s e r t t he i n s t rum en t t o t he app rop r i a t e imm ers ion de p th . The
bo i l i ng po in t i n Ind i ana i s 212°F .
• Be s u re t he r e i s a t l e a s t a t wo- i nch c l ea r ance be tw ee n the s t em
o r se ns i ng e l e men t a nd the bo t tom a nd s i de s o f t he con t a ine r .
• I f you r t he rm omet e r i s no t a c cu ra t e wi th in + / - 2 °F o f 212°F . ,
ad ju s t t he rmom ete r a cco rd i ng ly . The bo i l i ng po i n t me thod pe rm i t s
c a l i b r a t i on to w i t h in 1 .0 °F .
3 .Doc ume nt i n g Ca l ib ra t ion
Eac h t i me the rm omet e r s a r e ca l i b r a t ed , t he p roces s s hou ld be
docume n ted . T he food sa f e ty p rog ra m s hou ld i nc l ude a fo rm fo r
docume n t ing t he ca l i b r a t i on p roces s o f eac h the rmom ete r .
9 .E lec t r i ca l Metr o logy (D CLF )
An e l ec t r i c a l me t ro logy i s u s ua l ly t he f i r s t t o be s e t up i n a
coun t ry . I t i s r e l a t i ve ly s i mp le t o e s t a b l i s h , a nd in gene ra l t he demand
f rom indus t ry i s r e l a t i ve l y h igh . I n add i t i on , s eve ra l o the r m e t ro l ogy
d i s c ip l i ne s r equ i r e t he ba ck ing o f t he e l e c t r i c a l s t a nda rds t o de r ive
t he i r t r a cea b i l i t y , e spe c i a l l y t hos e o rga n i s a t i ons t ha t w i l l be s end ing
the i r s t anda rds fo r ca l i b r a t i on to t he na t i ona l l abo ra t o ry ·
21
Thi s se c t i on has be en l imi t ed t o wha t i s comm on ly known a s D CLF ,
wh i ch s t ands fo r dc t o l ow f r equency (≤ = 1M H z) e l ec t r i c a l m e t ro l ogy
and exc ludes t he m ore s pec i a l i s t a nd compl i ca t ed s ec t i ons t ha t u s e
h ighe r f r e quenc i e s ·
L ike s eve ra l o t he r d i s c ip l i ne s i n me t ro logy , t he p innac l e o f t he dc
t r ac eab i l i t y cha i n i s ba s ed on a phys i ca l phenom enon know n a s t he
Jo s ephs on Ef f e c t , w h ich i n t u rn i s t r a ceab l e t o f r e quency . The re a r e
on ly a f e w J os ephs on junc t i on sy s t e ms ope ra t i ona l i n t he w or ld , a nd
they a r e ve ry cos t l y t o pu rchas e a nd eve n m ore c os t l y t o run . The
Jo s ephs on junc t i on a ppa ra tu s i s t yp i ca l ly on l y ac t i va t ed , by t he f e w
na t i ona l r e s ea r ch in s t i t u t e s t ha t have the m, a f e w t im es a yea r t o
t r ans f e r 10 V dc ( t he cha ra c t e r i s t i c vo l t a ge fo r mos t sy s t e ms ) , t o ve ry
s t ab l e , z ene r -ba se d , r e f e r enc e sou rc es .
In t u rn , t he u se r s t hen ma i n t a i n a g roup o f zene r r e f e r enc es and , by
pe r iod i c i n t e r - compa r i s on o f t hem , ma i n t a in t he i r l abo ra t o ry s t anda rd
fo r dc vo l t age . S ome l abo ra t o r i e s p r e f e r t o u se t he a bso l u t e va l ue o f one
o f t he z ene r s , wh i l e m os t u se t he m ean va l ue o f t he g roup o f z ene r s . I f a
l abo ra to ry w an t s t o improve i t s dc capab i l i t y , i t s im p ly i nc r ea se s t he
number o f z ene r r e f e r ences i n t he g roup ·
To pu t t h i s i n pe r s pec t ive , t he J o se phson j unc t i on appa ra t u s c an
de l i ve r app rox i ma te ly 0 .1 ppm, w h i l e a g roup o f abou t 8 zene r
r e f e r e nces wi l l be ab l e t o ma i n t a i n 0 .3 ppm, and a g roup o f on l y 4 abou t
0 .8 ppm pe r ye a r . I n con t r a s t , i t i s r e l a t i ve ly e a s y to ma in t a i n t he
g roups o f z ene r r e f e r ences , w h i l e e s t ab l i s h ing the t r ans f e r va l ue o f t he
Jo s ephs on junc t i on i s ve ry d i f f i cu l t and r e qu i r e s a g r ea t de a l o f
equ ipm en t a nd expe r i e nce ·
In p r ac t i ce , ve ry f ew na t i ona l l a bo ra to r i e s ac tua l ly ne ed to have a
Jo s ephs on junc t ion s y s t em , and a g roup o f ze ne r r e f e r e nces i s u sua l ly
su f f i c i e n t . F rom th i s g roup , one zene r r e f e r ence i s se n t once a yea r t o a
22
l abo ra to ry t ha t ha s a J o se phson sys t e m to i mpor t t r a c eab i l i t y t o t he
g roup ·
How eve r t he ze ne r r e f e r ence s on ly have an ou t pu t vo l t a ge f i xed a t a
nomina l 10 V dc , a nd t hey ne ed t o be t r ea t ed we l l and no t l oaded wi th
l ow i mpedanc e m eas u r ing dev ic e s . Th i s mea ns t ha t , i n mos t c a s e s , t he
zene r r e f e r enc es a r e u s ed to t r ans f e r t he 10 V dc s t anda rd i n to a more
robus t e l e c t r i c a l m u l t i f unc t i on ca l i b r a to r w h ic h wi l l t hen s ou rce any
vo l t a ge ( a c o r dc ) f rom ze ro up to app rox im a te ly 1100 V . The se
ca l i b r a t o r s have a one -yea r spe c i f i ca t i on o f 3 .5 ppm on the i r ba s i c V dc
func t i on ·
The t r ac eab i l i t y o f Vac i s done by com par ing a V ac s igna l t o t he
equ iva l en t V dc by u s ing t he rma l t r ans f e r s t a nda rds . S ome t ime s t he s e
a r e i n s i de t he m u l t i f unc t i on ca l i b r a to r s and s ome t im es t hey a r e ex t e rna l
dev i c e s . They a r e r e l a t i ve l y s i mp le t o u s e bu t r equ i r e l o t s o f p r a c t i ce
and pa t i ence t o ge t cons i s t en t r e su l t s .
Res i s t anc e c apab i l i t y , a t t h i s l eve l , i s ma in t a i ned by hav i ng a s e r i e s
o f s t anda rd r e s i s t o r s . I n s ome ve ry h igh -ac cu racy c a se s , s pec i a l
s t anda rd r e s i s to r s a r e p l aced in a s t i r r ed o i l ba th , bu t t he more mode rn
" a i r r e s i s t o r s" a r e qu i t e s t ab l e enough a t < 3 ppm pe r yea r . O ne o r tw o
o f t he s e t ( 1 , 10 , 100 , 1k , 10k , 100k , 1M & 10M Ω ) a r e t he n s en t t o a
h igh - l e ve l l abo ra to ry onc e a yea r t o im por t t r a ce ab i l i t y , and t he
impor t ed va lue i s c ompared aga i n s t t he r e s t o f t he se t i n t he l abo ra t o ry ,
by i n t e r - com par i s on . Once aga in , t he s t anda rd r e s i s to r s a r e o f a f i xed
va lue and the i r va lue i s a l so t r ans f e r r e d i n t o a mu l t i f unc t ion ca l i b r a t o r
t o a l l ow gene ra l h igh - l e ve l c a l i b r a t i on ove r a w ide r ange ·
The c a l i b r a t i on o f a mu l t i f unc t ion ca l i b r a t o r i s done u s ing a
p rocedu re known a s a r t i f ac t c a l i b r a t i on . U s i ng on ly one ca l i b r a t ed 10
Vdc ze ne r r e f e r ence , a 1Ωand a 10kΩ s t a nda rd r e s i s t o r a s i t ' s s ou rce
t r ac eab i l i t y , t he ca l i b r a t o r i s ab l e t o de l ive r a ve ry wi de r ange o f V o l t s
( ac a nd dc ) , r e s i s t anc e , and cu r r e n t ( ac a nd dc ) , a l l o f wh i ch a r e
23
t r a c eab le t o i n t e rna t iona l s t anda rds . Mu l t i f unc t ion ca l i b r a to r s , t oge t he r
wi th a nu l l de t ec to r o r a good l ong s ca l e d i g i t a l m u l t i me t e r (D M M) , can
then be u se d to ca l i b r a t e mos t 8½ d i g i t m u l t i me te r s a nd o the r i ndus t r i a l
l eve l c a l i b r a t o r s ·
F o l low ing down the ca l i b r a t i on cha in , t he r e i s ano the r s t ep be fo re
t he ge ne ra l pu rpos e t e s t equ i pmen t l eve l i s r eache d . Fo r e xampl e , a
s i mp le 3½ d ig i t m u l t i me te r u s ed by the t housands i n i ndus t ry i s
d i f f i c u l t ( a lm os t i mpos s i b l e ) t o ca l i b r a t e u s ing on ly a mu l t i f unc t ion
ca l i b r a t o r bec ause t he m u l t i f unc t i on ca l i b r a t o r i s no t de s igned to do
th i s l eve l o f work . Eve n though the mu l t i f unc t ion ca l i b r a to r i s ve ry
acc u ra t e , i t l a cks t he r ange and add i t i ona l f unc t i ons r e qu i r ed by the
t yp i c a l m u l t i me t e r , suc h a s 20 amps , t he rm ocoup le s i mu la t i on ,
c apa c i t a nce , f r eque ncy e t c . To ca l ib r a t e a l l o f t he se func t ions on a
DM M , a mu l t i - p roduc t c a l i b r a t o r i s u se d ·
The mu l t i - p roduc t c a l i b r a to r ha s a Vdc s pec i f i ca t i on o f abou t 12
ppm pe r ye a r and i s t hus s u i t a b l e fo r c a l i b r a t i ng m os t DM M s up t o 6½
d ig i t s , a s w e l l a s many o f t he o the r l ow er l eve l c a l i b r a t o r s , D M Ms ,
pane l me t e r s e t c . t yp i ca l ly s een i n i ndus t ry ·
The re a r e ma ny coun t r i e s t ha t s imp l y u s e a m u l t i - p roduc t c a l i b r a to r
wi th a f e w a cces s o r i e s a s t he i r na t i ona l s t anda rd and , i nva r i ab ly , e ven
the h i ghes t - l e ve l l a bo ra to ry r e qu i r e s t he l owe r l eve l equ ipm en t t o be
ab l e t o pe r fo rm the i r t a s ks a dequa te ly . S o the de c i s ion abou t wha t t o
i n s t a l l i s u s ua l l y ba s ed f rom the bo t tom up , s t a r t i ng wi th a m u l t i -
p roduc t c a l i b r a t o r and then , i f t he marke t r equ i r e s t he l abo ra t o ry t o
ca l i b r a t e o the r l abo ra t o ry ' s mu l t i - p roduc t c a l i b r a to r s , i n s t a l l i ng a
mu l t i f unc t ion ca l i b r a to r wi th a f e w acc ess o r i e s . I n l im i t ed ca s e s , t he
na t i ona l l abo ra to ry w i l l need to go to f i xed va lue s s uch a s zene r
r e f e r e nces and s t anda rd r e s i s t o r s a nd , ve ry r a r e l y , a J o se phson j unc t ion
sy s t e m· The t ab l e s be low show how t r ac eab i l i t y i s de r ived and t he
t yp i c a l equ ipm en t and work l oad a s s oc i a t ed wi th each l eve l o f
l abo ra to ry . D o no t be m i s l ed by the t e rmino l ogy u s ed tha t a na t i ona l
24
l abo ra to ry has t o be a p r ima ry l eve l l abo ra to ry . The mos t im por t an t
i s sue i s t ha t t he na t iona l l abo ra to ry i s c apa b le o f p roduc i ng t r ac eab le
ca l i b r a t i on a t t he l eve l r equ i r ed by i t s marke t , w i th c ompe t ence and
e f f i c i ency ·
Labo ra to ry Le ve l Typ ic a l W ork load
Na t iona l r e s ea r c h in s t i t u t e (V dc± 0 .1ppm/ yea r )
Jos ephs on J unc t i on Sys t e m,
Qua n tum H a l l dev i ce s Zene r r e f e r enc es
F ixed r e s i s to r s e t c .
P r imary l eve l . abo ra to r i e s (Vdc ± 0 .5ppm /yea r )
Zene r r e f e r enc e g roup / s
F ixed s t anda rd r e s i s to r s , c apac i to r s e t c
The rm a l t r ans f e r s t anda rds
Refe r e nce d iv i de r s
Nu l l de t ec t o r / 8½ D MM Mul t i f unc t ion c a l i b r a to r s
Re fe r e nce D MM s
S econda ry l eve l l abo ra t o ry (Vdc ± 3 .5ppm /yea r )
Mul t i f unc t ion c a l i b r a to r
6½ to 8½ D ig i t mu l t ime te r Mul t i - p roduc t c a l i b r a t o r s
Labo ra to ry D MM s
Ter t i a ry l eve l l abo ra t o ry (Vdc ± 12ppm /yea r )
Mul t i - p roduc t c a l i b r a t o r
6½ Di g i t m u l t i me t e r
50 Tu rn co i l Bench & handhe ld D M Ms
P ane l m e te r s , t he rmome te r s
C lam p me t e r s , p roces s t oo l s
Os c i l l o s cope s
The e qu ipme n t t ha t wou l d no rma l ly be i n a t yp i ca l h i gh - l eve l
l abo ra to ry (m ix tu r e o f l abo ra to ry l eve l s ) wh i ch c ou ld ca t e r f o r mos t
i ndus t r i a l and l abo ra to ry w ork loa ds w ou ld i nc lude the fo l l owi ng : -
Lab s t a nda rds
25
2 x Re fe r e nce s t anda rds (8 ze ne r r e f e r e nce ce l l s )
1 x Ex te rna l ba t t e ry a nd cha rge r ( r e qu i r ed fo r i n t e r - com par i s on
jou rneys )
1 x T rans i t c a se ( t o ho ld one zene r and one e x t ba t t e ry fo r i n t e r -
compa r i s on )
1 x S e t s t anda rd r e s i s to r s ( 1 , 10 , 100 , 1k , 10k , 100k , 1M & 10MΩ )
1 x T rans i t c a s e ( t o ho l d tw o / th r e e s t anda rd r e s i s t o r s f o r i n t e r -
compa r i s on )
Hi gh - l eve l s t a t i on
1 x Re fe r e nce D MM (8½) w i th Ra t io func t ion
1 x Mul t i f unc t ion c a l i b r a to r
Ge ne ra l work s t a t i on
1 x Mul t i - p roduc t c a l i b r a t o r wi th s cope c a l op t . ( 600M H z)
1 x 6½ Di g i t D M M
1 x 50 Tu rn co i l
2 x S e t l ow the rma l l e ads
1 x S e t t he rmocoup l e t e s t l e ads
1 x Ha nd he ld D M M
Ot he r u s e fu l i t em s
26
1 x Dua l benc h power s upp ly (0 -30V > 2 amps )
1 x De cade r e s i s t ance box (1Ω to 10M Ω )
1 x De cade i nduc t a nce box (100µH to 11H )
1 x Hi gh vo l t a ge p robe (40kV )
1 x LCR M ete r
1 x 25Ω Res i s t anc e s t anda rd ( fo r t empe ra tu r e c a l i b r a t i on work )
1 x Ha nd he ld t he rmom ete r w i t h se l ec t i on o f p robes
1 x P C , P r i n t e r & me t / ca l so f t wa re e t c .
1 x Ca l Book (P h i l o sophy o f Ca l ib r a t i on i n P ra c t i ce )
I f r equ i r e d t o ca l i b r a t e i n s u l a t i on and i n s t a l l a t i on t e s t e r s
1 x Mul t i f unc t ion e l ec t r i c a l t e s t e r c a l i b r a t o r o r 1 x Se t h igh vo l t age
r e s i s to r s
1 x S e t l ow Ω , h i gh cu r r en t r e s i s t o r s
10 . TUR KI S H A C CR ED ITA TI ON AG ENC Y
10 .1 Wh at i s Acc red i ta t i on?
27
Ac cred i t a t i on i s a qua l i t y i n f r a s t ruc tu r e t oo l w h ic h suppo r t s t he
c r ed i b i l i t y a nd va l ue o f t he w ork c a r r i ed ou t by con fo rm i ty a s s e ss me n t
bod ie s and t hus o f t he c o r r e s pond ing a t t e s t a t i ons i s sue d by them ( t e s t
and in s pec t ion r epo r t s , c a l i b r a t i on ce r t i f i c a t e s , c e r t i f i c a t i ons o f
mana gemen t sy s t e ms , p roduc t s and pe r s onne l and o the r a t t e s t a t i ons ) .
Ac c red i t a t i on o f con fo rmi ty a s s e s s men t bod ie s i s c a r r i ed ou t aga i n s t
g loba l ly acce p ted r equ i r em en t s se t ou t i n i n t e rna t i ona l s t anda rds
de f in i ng compe tence c r i t e r i a f o r t he ca t ego ry o f con fo rm i ty a s s e s sm en t
body , aga i n s t supp l emen t a ry s ec t o r spec i f i c r equ i r em en t s and a ga in s t
gu idanc e docume n t s f rom in t e rna t iona l a nd r eg iona l coope ra t i on
o rgan i s a t i ons o f acc r e d i t a t i on bod i e s .
A p roduc t o r se rv i ce acc ompan ie d by a c on fo rmi t y a t t e s t a t i on de l i ve r ed
by an ac c r ed i t ed con fo rm i ty a s s e s sm en t body i n sp i r e s t r u s t a s t o t he
compl i anc e w i t h app l i ca b l e spe c i f i e d r equ i r eme n t s . The reby
acc r ed i t a t i on f a vou r s t he e l i mina t ion o f t e chn i ca l ba r r i e r s t o t r ade .
A g loba l a ccep t ance o f t he se rv i ce s p rov i ded wi th a n ac c r ed i t a t i on i s
a l s o sub j ec t t o som e que s t ions , a s t o e s t ab l i sh a con f idenc e fo r t he
qua l i t y o f t he ac c r ed i t a t i on s e rv i c e i t s e l f . The t r u s t i ng me chan i sm
be tw ee n acc r e d i t a t i on bod ie s i s c ons t ruc t ed on t he mu l t i l i t e r a l
ag r ee men t s a t t he i n t e rna t i ona l and r e g iona l a c c r ed i t a t i on body
o rgan i s a t i ons , l i ke IAF ( I n t e rna t iona l A cc red i t a t i on F o rum) , ILA C
( In t e rna t iona l L abo ra t o ry A cc red i t a t i on Coope ra t i on ) , E A (Europen
Coope ra t ion fo r A cc red i t a t i on ) , e t c .
TU RKA K , s t a r t ed t o p rov i de acc r e d i a t i on s e rv i ce s i n 2001 and be came a
s i gna to ry o f M LA wi th E A fo r a l l t he ava i l ab l e a cc r ed i t a t i on s che mes a t
2008 . Cur r en t l y TU RKA K i s a f u l l mem ber o f EA , IAF and ILA C.
10 .2 Pu rp os e o f Es tab l i s hme nt
Tu rk i s h Ac c red i t a t i on A gency (TÜ RKA K ) i s e s t ab l i s hed , r e l a t ed
wi th t he P r i me M in i s t ry , sub j ec t t o p r iva t e l aw p rov i s i ons , w i th i t s
headqua r t e r s i n A nka ra , a s a l e ga l en t i t y ha v ing a dmin i s t r a t i ve a nd
28
f i nanc i a l au t onomy , t o a cc r ed i t t he l oca l and in t e rna t i ona l bod ie s
r ende r i ng l abo ra t o ry , c e r t i f i c a t i on a nd in s pec t ion s e rv i ce s , e n su re t hem
to ope ra t e i n acco rda nce w i th e s t ab l i shed na t iona l and i n t e rna t iona l
s t anda rds , and t he r eby ens u r ing i n t e rna t iona l r ecogn i t i on o f p roduc t /
s e rv i ce , sy s t em , pe r s onne l a nd l abo ra t o ry ce r t i f i c a t e s .
10 .3 Ca l ib ra t ion Lab ora tor i e s Ce r t i f i ca t ion
Ma ny coun t r i e s a round the w or ld de t e rm ine the t e c hn ica l
compe tence o f t he i r l a bo ra to r i e s by the he lp o f t he i r a cc r e d i t a t i on
sy s t e ms .
O ne bod ie s m ay be r e spons ib l e f o r t he a cc r ed i t a t i on o f
l abo ra to r i e s i n any c oun t ry . T he du t y o f l abo ra to ry a cc r ed i t a t i on in ou r
coun t ry ha s be en g iven t o t he T u rk i s h Ac c red i t a t i on Age ncy (TÜ RKA K )
unde r l a w no 4457 .
A s o f t oday , ISO / IE C 17025 and ISO 15189 s t anda rd i s t aken a s
t he ba s i s f o r l abo ra to ry a cc r ed i t a t i on pu rpos es . Th i s S t anda rd i s
r ecogn i zed w or ldw ide . T he r equ i r emen t s o f t h i s s t anda rd p rov i de fo r t he
gene ra l r e qu i r em en t s on a l abo ra t o ry ' s qua l i t y m anagem en t sy s t e m a nd
t ec hn ica l compe tence .
Labo ra to r i e s ac c r ed i t ed ac co rd ing t o ISO / IE C 17025 and IS O
15189 a r e r e - eva lua t ed pe r i od i ca l ly e va lua t ed by the acc r e d i t a t i on body
and dec i s ion i s made fo r t he m a in t enance o f acc r e d i t a t i on bas ed on
r e s u l t s ob t a ined .
Labo ra to r i e s i n t end ing t o ma i n t a i n acc r e d i t a t i on a r e r equ i r e d t o
pa r t i c ipa t e i n t e r - l a bo ra to ry com par i s on and p ro f i c i enc y t e s t i ng
p rog rams on the i r s cope o f ac c r ed i t a t i on and ach i eve s ucce ss fu l r e su l t s .
29
11 UM E(ULU S AL M ETRO LOJİ ENS Tİ TÜS Ü )
One o f t he mos t s i gn i f i c an t f ac to r s i n p roduc t ion and qua l i t y
con t ro l i s t he r e l i ab i l i t y o f m eas u reme n t s . Th i s r e l i ab i l i t y can on ly be
ach i eved by ca l i b r a t i ng t he mea su r i ng dev ice , e . g de t e rmin i ng the
magn i tude o f i t s me as u remen t e r ro r w i th a be t t e r , m ore a ccu ra t e ,
i n s t rume n t . How eve r , t h i s more acc u ra t e i n s t rum en t a l s o ne eds t o be
ca l i b r a t ed , a nd in t h i s wa y a cha i n i s e s t ab l i s hed . V ia t h i s cha i n , a l l
mea su re men t s a r e connec t ed to t he 7 ba s e S I Un i t s ; t he Me te r ,
K i log ram , Se cond , K e lv i n , Cande la , Am pere and M ol , a s de f ined by
BIP M, t he i n t e rna t i ona l c e n t e r f o r m e t ro l ogy .
Al mos t a l l deve loped and de ve lop i ng coun t r i e s ha ve a na t iona l
c en t e r , hav ing r e l a t i ons wi th BIP M. T he ma in ob j ec t ive s o f t he s e
cen t e r s a r e t o bu i l d and ma i n t a i n na t iona l s t anda rds fo r a l l
mea su re men t s ca r r i e d ou t w i th i n t ha t coun t ry , and t o c a l i b r a t e t he
mea su re men t s t a nda rds and dev ic e s o f l ow er l eve l l a bo ra to r i e s . T h i s
cha i n ex t ends t o p roduc t ion , qua l i t y con t ro l and to a l l s c i e n t i f i c ,
comm erc i a l and m i l i t a ry de v ice s w h ich a r e u se d fo r mea su rem en t s . I n
t h i s wa y , a l l m eas u rem en t s a r e t hen t r acea b le t o t he na t i ona l s t anda rds .
Na t iona l s t a nda rds a r e l i nked to t he s t a nda rds i n o the r coun t r i e s o r
t hos e o f B IP M by a p roce ss o f i n t e rna t iona l com par i s ons . Th i s i s c a l l e d
t r ac eab i l i t y .
Na t iona l c en t e r s , w i th t he se conda ry l e ve l a c c r ed i t ed l a bo ra to r i e s ,
f o rm the na t i ona l mea su rem en t s y s t em and c oo rd ina t e t he i r a c t i v i t i e s .
The na t i ona l c en t e r p rove s i t s p ro f i c i ency v i a compa r i s ons wi th o the r
30
na t i ona l c en t e r s w i th i n t e rna t i ona l compa r i s ons wh i ch a r e f r equen t l y
be ing obs e rved by BIP M w i th t he i n fo rm a t ion r e l ayed to o t he r na t iona l
c en t e r s t h rough va r ious pub l i ca t i ons .
The s tud i e s r e l a t ed t o i n t e rna t iona l m eas u reme n t s y s t em s t a r t ed on
25 Ma y 1875 whe n Mi ra l ay H us nu Bey had s igne d the M e te r Conven t i on
on be ha l f o f t he O t t oman Empi r e . T hough t he O t t oman Empi r e w as one
o f t he 20 s t a t e s w ho w ere t he founde r s o f t he Me te r Conven t i on , t he r e
we re no s ign i f i can t de ve lopm en t i n t h i s f i e l d un t i l t he l aw o f We igh t s
and M eas u re s ( l aw no 1781 ) ha s been pu t i n ac t on 26 M arch 1931 .
Af t e r t he se cond w or ld wa r , nee d fo r an i n t eg ra t ed sy s t e m o f
me t ro logy w as f e l t s t r ong ly i n T u rkey . On t he o the r hand , t he vo l ume o f
t he marke t f o r c a l i b r a t i ons w as no t l a rge enough t o j u s t i f y a ma jo r
i nves tm en t i n me t ro logy un t i l 1980 .
The P r ime M in i s t ry o f T u rkey ha s a s ked TÜ BİTA K (Sc i en t i f i c and
Tec hn ica l Re sea rch Counc i l o f T u rkey ) t o e s t ab l i s h t he na t i ona l
mea su re men t s y s t em in t he ea r ly e i gh t i e s . I n i t i a l s t ud i e s be gan i n 1982 ,
t he f e a s ib i l i t y s tudy w as acc ep ted by a l l t he r e l e van t pa r t i e s i n T u rkey ,
and the Na t iona l M e t ro logy In s t i t u t e (U ME ) w as founde d in 1992 , a s
pa r t o f T ÜBİT AK .
UM E m oved to ne w bu i ld ings i n J anua ry 1994 a nd the o f f i c i a l
open ing w as unde r t aken by the De pu ty P r ime Mi n i s t e r on M ay 4 th ,
1994 . T he re a r e tw o bu i l d ings , na med B lock A and B lock B . I n B lock A ,
t he r e a r e 21 l abo ra t o r i e s , a c ompu te r cen t e r , an e l ec t ron i c works hop ,
con fe r e nce and s em ina r rooms , and o f f i ce s . Eac h l abo ra to ry has
env i ronm en ta l c on t ro l and a l l t he pa r a me te r s s uch a s t em pera tu r e ,
humid i ty and a i r p r e s s u re a r e mea su re d and r eco rde d by a fu l l y
au tom a te d com pu te r i zed env i ronme n ta l con t ro l c en t e r . The m os t
se ns i t i ve l abo ra t o r i e s a r e unde rg round and s pec i a l p r ec au t i ons a r e t ake n
in o rde r t o min i miz e v ib r a t i ons . I n B lock B , t he r e a r e admi n i s t r a t i ve
o f f i ce s , l i b r a ry , c a f e t e r i a , ma ch ine shops and s uppo r t g roup rooms .
31
In a dd i t i on to t he ma ins pow er s upp ly , t he r e i s a back -up gene ra t o r
and a l l t he e l ec t ron i c s and con t ro l c i r cu i t s a r e f ed by t wo pa ra l l e l
un in t e r rup t ab l e pow er supp l i e s . I n add i t i on , som e equ ipme n t have the i r
own ba t t e ry back -up s ys t ems .
UM E p roduc es l i qu i d n i t r oge n and l i qu i d he l i um fo r i t s ow n us e and
a lm os t se l f s u f f i c i en t i n t e rms o f e l ec t ron i c s and ma ch ine s hops .
11 .1 OBJEC TIV ES o f U ME :
* T o e s t a b l i s h a nd m a in t a in na t iona l meas u rem en t s s t a nda rds i n
acc o rdance w i t h t he S I U n i t s .
* To ens u re t he t r ac eab i l i t y o f na t iona l me as u remen t s t anda rds
t o i n t e rna t iona l s t anda rds .
* To e s t a b l i s h a na t iona l mea su rem en t s y s t em and p rov ide
se rv i ce s t o t he l a bo ra to r i e s wi th in t h i s sy s t em in t e rms o f ca l i b r a t i on ,
t r a i n ing , cons u l t ancy and o t he r me chan i s ms .
* To ens u re t he s u i t ab i l i t y o f t he l abo ra t o r i e s t ha t app ly t o j o in
t he T u rk i s h Ca l i b r a t i on Se rv i ce (T KS ) and t o o rgan iz e t he i r
a cc r ed i t a t i on .
* To con t r ibu t e t o r e s ea r c h and deve l opmen t i n t he a r ea s o f
mea su re men t t e chn i ques , c a l i b r a t i on and bas i c m e t ro l ogy a t
i n t e rna t i ona l l eve l .
* T o deve lop h i gh t echno logy p roduc t s and t o d i s s em ina t e t hem
v i a i t s deve l oped in f r a s t ruc tu r e .
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* T o inc r ea s e t he qua l i t y o f p roduc t s p roduced in Tu rkey by
p rov id ing t he me as u remen t i n f r a s t ruc tu r e t h rough t he na t iona l
mea su re men t s y s t em .
* T o r ep re se n t T u rkey a t an i n t e rna t iona l l eve l i n t he f i e l d o f
me t ro logy .
13 . DEF İN İ TİO NS
Tes t : A t echn i ca l ope ra t i on tha t cons i s t s o f t he de t e rmina t ion o f
one o r more
cha ra c t e r i s t i c s o r pe r fo rm ance o f a g iven p roduc t , ma t e r i a l ,
equ ipm en t , o rga n i s m, phys i ca l
Ca l i b r a t i on me thod : D e f ined t ec hn ica l p roc edu re fo r pe r fo rm ing a
ca l i b r a t i on .phenome non , p roce ss o r s e rv i c e a cco rd ing to a s pec i f i e d
p rocedu re .
Tes t m e thod : De f ined t e chn ic a l p roce du re fo r pe r fo rmi ng a t e s t .
Ve r i f i c a t i on : Conf i rma t ion by exam ina t ion and p rov i s i on o f
ev ide nce t ha t s pec i f i ed r equ i r eme n t s have bee n me t .
Re fe r e nce s t anda rd : A s t anda rd , gene ra l l y o f t he h ighe s t
me t ro log i c a l qua l i t y a va i l ab l e a t a g i ven loca t ion , f r om wh i ch
mea su re men t s ma de a t t ha t l oca t ion a r e de r ived .
Re fe r e nce ma te r i a l : A ma te r i a l o r s ubs t ance one o r more p rope r t i e s
o f w h ic h a r e s u f f i c i en t l y w e l l e s t a b l i s hed to be u s ed fo r t he c a l i b r a t i on
o f an appa ra tu s , t he a s s e s s men t o f a mea su rem en t m e thod , o r f o r
a s s i gn ing va l ues t o ma t e r i a l s .
Ce r t i f i ed r e f e r ence ma te r i a l (CRM) : A r e f e r ence ma te r i a l one o r
more o f w hos e p rope r ty va lues a r e ce r t i f i ed by a t e chn ica l ly va l i d
p rocedu re , a ccom pan ied by o r t r ace ab le t o a ce r t i f i c a t e o r o the r
docume n ta t i on w h ich i s i s s ued by a c e r t i f y i ng body .
Trac eab i l i t y : The p rope r ty o f a r e s u l t o f a me as u remen t whe reby i t
c an be r e l a t ed t o a pp rop r i a t e s t anda rds , gene ra l l y i n t e rna t iona l o r
na t i ona l s t a nda rds , t h rough an unb roken c ha in o f com par i s ons .
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Ac curacy : how c lo s e a m eas u reme n t r ead i ng i s t o t he ' t r ue ' va lue
o f t he pa r ame t e r be i ng meas u red
P rec i s ion : how r e pea t a b l e o r c lo s e ly -g rouped t he me asu re men t
r ead i ngs a r e
Res o lu t i on ; t he l eve l o f d i s c r im ina t ion tha t t he m eas u r ing
equ ipm en t c an show ; t he s ma l l e s t un i t change tha t i t c a n d i s ce rn o r
de t e c t .
S ens i t i v i t y : t he s ma l l e s t cha nge in t he i npu t ( s t imu l us ) t ha t c a use s
a d i s ce rn ib l e c hange i n t he ou tpu t
S tab i l i t y : t he t ende ncy o f a mea su r i ng equ i pmen t no t t o ' d r i f t ' o r
deg rade ove r t im e and u s age
14 CO NC LU S IO N
I d i d my s umme r p r ac t i ce a t Ö lç me Kon t ro l S i s t emle r i Ka l ib r a s yon
Labo ra tuva r C ihaz l a r ı S anay i V e T ica r e t L td . Ş t i . I l e a rn s ome
de f in i t i ons abou t t he me t ro logy a nd ca l ib r a t i on . I l e a rned c a l i b r a t i on
t e rm s , c a l i b r a t i on p roc edu re s . I s t ud i ed l abo ra t o ry and ca l ib r a t e
ca l i ppe r , m ic rome te r . I t h ink th i s s umm er p r ac t i ce ve ry u se fu l f o rm m e .
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