5/18/2015

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CHO MNG CC BN N VI MN

HIU CHUN THIT B O LNG

KHOA IN - T NG HA

TRNG CAO NG NGH DU KH

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GII THIU

CONTROLLER

PROCESS

FINAL CONTROL ELEMENTS

MEASURING MEANS

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TM QUAN TRNG CA VIC HC/HC

HC, HC l so snh cc gi tr ca thit b ovi thit b chun bit nh gi sai s, cc c trng k thut o lng v c thchnh li

Vn hnh thnh cng mt qu trnh phthuc vo chnh xc v c tnh ca tngthit b o trong mch iu khin

HC, HC thit b gip cho qu trnh cngngh vn hnh an ton trong phm vi kthut cho php

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TM QUAN TRNG CA VIC HC/HC

HC, HC cn thit khi thay i cc thng s ca qu trnh cng ngh hay thit b.

Hiu chun, hiu chnh l t nguyn. Mt h thng o lng, iu khin m

bo tin cy khi tng phn t trong h thng phi tin cy.

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HC, HC li c thc hin trong mt s trng hp sau:

l Sau mt thi gian vn hnhl Thit b mi trc khi a vo lp

tl Thit b sau khi sa chal Khi thay i v tr lp t thit b ol

TM QUAN TRNG CA VIC HC, HC

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Mt thit b c HC, HC hon ho th ctnh ca n nm trong m t k thut canh ch to

Tng thit b o trong mch iu khinc HC, HC hon ho m bo cho hthng hot ng chnh xc v an ton

S vn hnh ca tng thit b o trongmch iu khin nh hng ti tt c ccthit b o khc trong cng h thng

S CN THIT PHI HC, HC TNG THIT B O

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PHM VI O V SPAN

Phm vi o: Tp hp cc gi tr ca i lng o m sai s ca PT c xem l nm trong gii hn quy nh

Span l s chnh lch gia gi tr gii hn trn v gi tr gii hn di ca thang o ng dng.

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PHM VI O V SPAN

V d: Mt transmitter nhn gi tr vo t 0 50 psi, tn hiu ra ca n l 4 20 mA. Ta c:

l Phm vi o tn hiu vo: 0 50 psil Phm vi o tn hiu ra: 4 20 mAl Span tn hiu vo: 50 psil Span tn hiu ra: 16 mA

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S DNG SPAN HC, HC

INPUTSPAN

GI TR INPUT %

GI TR OUTPUT

OUTPUT SPAN

50 PSI

50 PSI 100 % 20 mA

16 mA25 PSI 50 % 12 mA

0 PSI 0 % 4 mA

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CHNH XC

chnh xc ni n mc gn nhau gia gi tr o v gi tr chun

chnh xc thng c th hin bng % span ca thit b o

Nu thit b o c sai s ln hn sai s cho php th cn phi sa cha, hiu chun, hiu chnh li.

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TNH TON CHNH XC

chnh xc = ( lch/span) x 100% V d: mt transmitter c di o 0 50 psi,

ng ra 4 20 mA. p sut vo l 25 psi, ng ra lc ny l 13,6mA. chnh xc c tnh nh sau: chnh xc = [(13,6 12)/16] x 100%

= 10%

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H S KHUCH I

H s khuch i = Output span / Input span

H s khuch i nh hng n chnh xc ca thit b

H s khuch i cao cho php HC, HC chnh xc hn

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H S KHUCH I

V d: Mt transmitter nhit c thang o input 0 5000C v thang o tn hiu ra l 4 20mA. H s khuch i c tnh nh sau:l Span tn hiu vo: 5000Cl Span tn hiu ra: 16mAl H s khuch i = 16/500 = 0,032mA/0C

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CHM

chm c ngha l lp li hoc mc ti to sau cc ln o c lp ca cng mt gi tr thc

Kh nng to ra cc gi tr ra ging nhau vi cng mt gi tr vo cc ln o khc nhau

chnh xc thit b o cng cao th chm cng cao

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CHNH XC V CHM

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CHUN

xc nh chnh xc v chm ca thit b o, n phi c so snh vi chun bit.

Chun l thit b dng HC, HC cc thit b o khc m n c HC, HC v cp giy chng nhn bi cc t chc tiu chun quc gia hoc quc t:l ISA: International Standard Associationl NIST: the Nation Institute of Standard and

Technologyl ANSI: American National Standard Institute

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CHUN

Di o. Cp chnh xc. khng m bo o. n v. phn gii.

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SAI LCH ZERO

L trng hp tn hiu ng ra ca thit b o cao hn hoc thp hn gi tr mong i khi tn hiu vo t gi tr zero.

Kim tra sai lch zero thng d pht hin khi tin hnh HC/HC.

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SAI LCH ZERO

V d: Mt transmitter c range: 0-500C

Gi tr input Gi tr outputim th Input Mong mun Thc t

10% 50C 5,6mA 5,8mA30% 150C 8,8mA 9,0mA50% 250C 12,0mA 12,2mA70% 350C 15,2mA 15,4mA90% 450C 18,4mA 18,6mA

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20mA 100%

80

60

40

20

4mA 0%0% 10 20 30 40 50 60 70 80 90 100%00C 500C

L tng

Thc t

SAI LCH ZERO

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SAI LCH SPAN

Xy ra khi span ca tn hiu ra khng tng ng vi span ca tn hiu vo

V d: Mt transmitter nhit c di o t 0 n 50oC, sai lch Span xy ra khi tn hiu vo l m tn hiu ra khng l

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20mA 100%

80

60

40

20

4mA 0%0% 10 20 30 40 50 60 70 80 90 100%00C 500C

L tng

Thc t

SAI LCH SPAN

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20mA 100%

80

60

40

20

4mA 0%0% 10 20 30 40 50 60 70 80 90 100%00C 500C

L tng

Thc t

SAI LCH SPAN

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S KHNG TUYN TNH

L trng hp m th quan h vo ra khng phi l ng thng

Khc phc s khng tuyn tnh khng phi l nhng iu chnh n gin m i hi phi sa cha

C th nhn bit s khng tuyn tnh nh bng s liu hoc th quan h vo/ra

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20mA 100%

80

60

40

20

4mA 0%0% 10 20 30 40 50 60 70 80 90 100%00C 500C

L tng

Thc t

S KHNG TUYN TNH

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20mA 100%

80

60

40

20

4mA 0%0% 10 20 30 40 50 60 70 80 90 100%00C 500C

L tng

Thc t

S KHNG TUYN TNH

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20mA 100%

80

60

40

20

4mA 0%0% 10 20 30 40 50 60 70 80 90 100%00C 500C

L tng

Thc t

S KHNG TUYN TNH

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S KHNG TUYN TNH

Kh nhn dng Thng khng iu chnh c, i khi

vic iu chnh dn ti sa cha thit b

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Gi tr input Gi tr output

im th Input Mong mun Tng Gim

10% 20 psi 5,6mA 5,4mA 5,6mA

30% 60 psi 8,8mA 8,6mA 9,0mA

50% 100psi 12,0mA 11,5mA 12,5mA

70% 140psi 15,2mA 14,4mA 16,0mA

90% 180psi 18,4mA 17,0mA 19,0mA

SAI S HI SAI

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SAI S HI SAI

Ti cng mt gi tr ng vo, thit b s cho cc gi tr ra khc nhau ty thuc vo hng cp tn hiu vo (tng hay gim)

Sai s hi sai ch yu xut hin cc thit b o bng c kh.

Sai s hi sai nh hng n chm trong mt thit b o

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VNG KHNG NHY

L phm vi m tn hiu vo thay i nhng khng thy s thay i ng ra

Vng khng nhy c th nh hng n chm

C th gim vng khng nhy bng cch tng h s khuch i.

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V D - QUAN TRC GC

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V D - QUAN TRC GC

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V D - BO CO HIU CHUN

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V D - BO CO HIU CHUN

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V D - CHNG NHN KIM NH

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V D - CHNG NHN CHUN

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V D - CHNG NHN CA CHUN

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V D - CHNG NHN CA CHUN

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B TR THIT B CHO VIC HC, HC

Vic HC, HC phi ti to tn hiu vo ph hp vi cc thng s ca qu trnh cng ngh thc t

Thit b c HC, HC phi c lp t khi HC phi ging nh chng c lp t trong qu trnh thc t.

Mi lin h gia cc thit b trong h thng l hp l

Chun vo v chun ra phi ph hp

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B TR THIT B CHO VIC HC, HC

Ngun cp cho cc thit b trong h thng ph hp

u ni in phi m bo tip xc tt Phn p sut phi m bo khng r rCh : vic b tr lp t c hon ho,

phi hiu bit tt c chc nng ca thit b c HC trong qu trnh cng ngh ca n

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Ngun cp

Chun ng vo

Ngun cp

Thit b cn HC-HC

Chun ng ra

B TR THIT B CHO VIC HC, HC

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NGUYN TC HIU CHUN

Xc nh cc chun vo ra cho ph hp Tin hnh kt ni cc thit b theo ng s

HC To ra tn hiu vo th hin bin qu trnh

v a n ng vo ca thit b cn HC Ng ra ca thit b s hin th gi tr tng

ng

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NGUYN TC HIU CHUN

Thay i gi tr ng vo cc im khc nhau trn ton thang o

Ghi li cc gi tr ra tng ng v v th quan h vo ra

Da vo th nh gi sai lch v thc hin hiu chnh nu cn

Xc nhn li vic HC, HC bng cch kim tra li cc im va kim tra.

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NGUYN TC HIU CHUN

Ch : Tt nht l kim tra 5 im chia u trn

ton thang o theo chiu tng v chiugim: 0%, 25%, 50%, 75% v 100%

Phi bao gm im th 50%, im cao nhtv im thp nht

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NGUYN TC IU CHNH THIT B

iu chnh zero trc. Zero l im thp nht ca thang o ng dng

iu chnh span im cao nht ca thang o ng dng

iu chnh span c th nh hng ti zero, do sau khi iu chnh span phi kim tra li zero

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CHUN VO

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CHUN VO

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CHUN RA

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THIT B TO P SUT

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MT S THIT B CHUN

Lnh vc p sut d: Hin nay chun cao nht ca nc ta l p k pittng chun Ruska, di o

0.5-1000 bar chnh xc 0.004%

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MT S THIT B CHUN

Lnh vc chn khng v p sut tuyt i: Hin nay chun cao nht ca nc ta l p k pittng chun Ruska 2465, di o 14 mbar -70 bar tuyt i,

chnh xc 0.0008%

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MT S THIT B CHUN

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HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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ng h p sut dng ch p sut ti chca qu trnh

p sut tc ng vo phn t cm bin nhi lm n gin n v dui ra.

Ma st, s mi mn c th gy ra cc sailch nh sai lch zero, sai lch span, tr vs khng tuyn tnh

Hiu chun ng h p sut bao gm vichiu chnh cc b phn sao cho kim ch thch ng p sut vo.

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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Kim tra bn ngoi Kim tra cc ch tiu k thut Kim tra o lng

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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Kim tra bn ngoip k cn hiu chun phi tnh trng tt:

khng b n mn, bn, nt vMt knh trong sut khng c vt nt v cc

khuyt tt khc

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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Kim tra ch tiu k thutKim tra n v o, phn gii, cp chnh xc ca p k cn hiu chun

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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Kim tra o lngChn chun v cc phng tin phChun c gii hn o trn khng nh hn ca

p k.

khng m bo o hoc SSCBCP SSCBCP PT

Nhit mi trngt = 20 2 0 C vi PT c k < 0,4t = 20 5 0 C vi PT c k 0,4

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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Kim tra o lngXc nh s im hiu chun:k < 0.25 chn t nht 10 im0.25 k < 1 chn t nht 6 imk > 1 chn t nht 5 im

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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Ngun cp

Chun ng vo

ng h p sut

Ngun p sut

U NI

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U NI

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Kim tra o lngTrnh t thao tc:T t tng p sut n gii hn o trn caPT sau kha cc van li v gi nguyntrong 5 pht kim tra s r r p suttrong h thng.X p sut t t tr v trng thi ban u.iu chnh im 0 nu c th.Tng v gim p sut theo cc im nh

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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Kim tra o lngGhi cc kt qu vo bin bn hiu chun

Tnh ton s b v iu chnh li nu cn thitTnh ton khng m bo o ca PT

HIU CHUN NG H O P SUT KIU L XO V HIN TH S

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S DNG COMMUNICATOR CU HNH CHO TRANSMITTER

Commu-nicator

Transmitter 24VDC250 mA

+

-

Chun ng rap sut vo

Transmitter 24VDCmA +

-

Chun ng ra

p sut vo

S kt ni

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S DNG COMMUNICATOR CU HNH CHO TRANSMITTER

Cc chc nng chnh: t di o cho transmitter Chnh zero, chnh span Xem gii hn trn v di ca cm bin La chn kiu sensor vo i vi

transmitter nhit Loop test

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HART V SMART DEVICES

Highway Addressable Remote Tranducer Cho php trao i tn hiu gia hai thit b,

cng vi tn hiu tng t (analog). c pht trin u nhng nm 80 bi

Rosemount Inc. Nay do HART Communication Foudation qun

l. Cc thit b hin trng c h tr HART =>

Smart Devices 5/18/2015

BT200 BRAIN TERMINAL

L thit b kt ni ring ca hng Yokogawa. C cc tnh nng v kt ni tng t nh HART

Communication. Khng c s ng h rng ri ca cc hng sn

xut thit b trn Th gii bng HART Communication.

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HC CHO TRANS. P SUTKIU IN T, TN HIU ANALOG

PV=p sut ti ng vo Span = URV LRV Output = 4mA khi PV = LRV Output = 20mA khi PV-URV

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U NI CHO TRANS. P SUT KIU IN T, TN HIU ANALOG

Ngun cp

Chun ng vo

Ngun cp

Transmitterp sut

Chun ng ra

Ngun p sut

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CHUN VO / RA

Chun vo l mt ng h p sut dng o vhin th p sut cp cho transmitter

Chun ra l mt ng h mA, dng o tn hiura tng ng vi cc gi tr p sut vo

Ngun p sut c cp t bm to p hoc tngun kh sau khi qua regulator

Cc chun vo ra phi c di o ln hn hoc bngdi o ca transmitter

Cc chun vo ra phi chnh xc cao hntransmitter theo quy nh

Ngun cp thng thng l 24VDC

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Kim tra bn ngoi Kim tra k thut Kim tra o lngCc mc trn yu cu tng t nh quy trnh

hiu chun p k l xo, hin th sChun ampe k c cp chnh xc cao hn t

nht 2 ln so vi b chuyn i.

QUY TRNH HIU CHUN

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Tnh ton s b chnh xc ca transmitter, nu khng t th tin hnh hiu chnh

HC zero trc, sau l span v kim tra li zero. C th phi chnh li zero sau khi iu chnh span

Sau khi zero v span tha mn, kim tra li cc im ln cui

HC CHO TRANS. P SUT KIU IN T, TN HIU ANALOG

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Ch : Ngun p sut c tng t t trnh p

sut vt qu di o ca transmitter Khi p sut tin gn n im mun kim

tra th dng nt chnh tinh ca bm to p iu chnh.

HC CHO TRANS. P SUT KIU IN T, TN HIU ANALOG

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TRANSMITTER P SUT CHNH LCH

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PV = PH - PL Span = URV LRV Output = 4mA khi PV = LRV Output = 20mA khi PV-URV

TRANSMITTER P SUTCHNH LCH

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U NI TRANSMITTER P SUT CHNH LCH

Ngun cp

Chun ng vo

Ngun cp

Transmitterp sut

Chun ng ra

Ngun p sut

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HC TRANSMITTER P SUT CHNH LCH

Ch : Cc yu cu i vi chun vo, ra tng t

nh trng hp ca transmitter p sutbnh thng

Qu trnh kim tra 5 im v hiu chnhging nh trng hp transmitter p sut 1 ng vo

p sut c cp vo ng p sut cao catransmitter

Ng vo p sut thp c thng vikhng kh

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HC LT BNG CT P TNH-NGUYN L

DP = rghr : Khi lng ringg : gia tc trng

trng (g = 9,8 m/s2)

h : cao ct p

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0m

10m

2m

HC LT BNG CT P TNH-NGUYN L

PV = DP LRV = 0mH20 URV = 8mH20

PV = DP LRV = 0mH20 URV = 10mH20

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HC LT BNG CT P TNH-NGUYN L

Bn xng, h=10mr = 737 kg/m3Py = 7.37 mH20Span = 7.37 mH20URV = 0 mH20LRV = 7.37 mH20

0m

10m

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Ngun cp

Chun ng vo

Ngun cp

Transmitter mc

Chun ng ra

Ngun p sut

HC LT BNG CT P TNH- U NI

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HC LT BNG CT P TNH- U NI

Ngun p sut c cp t bm hoc t ngun kh sau khi qua regulator

Ngun p sut ng thi c a n ng vo p sut cao ca transmitter v n chun vo ch th

Ng p sut thp ca transmitter c thng vi kh quyn

u ra ca transmitter c ni n chun ra

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CHUN VO RA

Chun vo l mt ng h o p sut Chun ra l ng h mA chnh xc ca chun phi ln hn

chnh xc ca transmitter

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KIM TRA 5 IM

Kim tra 5 im: Vic kim tra 5 im cng c thc hin

ging nh cc trng hp khcCc lu : Phi ch xc nh im zero v span

cho ng trong trng hp transmitter c lp t cao hn hoc thp hn mc ti thiu.

Transmitter o mc ch c th o c mc t v tr lp t tr ln 5/18/2015

HC FT THEO NGUYN L CHNH P

Nguyn l: Khi cht lng c lu lng khng i i

qua vng gii hn s tng vn tc v gim p sut

o p sut pha trc v pha sau vng gii hn s xc nh c lu lng nu bit trc c tnh ca cht lng

Ng vo p sut cao v thp ln lt c lp pha trc v pha sau thit b gim p

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HC FT THEO NGUYN L CHNH P

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HC FT THEO NGUYN LCHNH P

V d: Lu lng: 0 100 m3/h p sut to ra: 0 30 psi Span = 30 psi URV = 0 psi LRV = 30 psi

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Ngun cp

Chun ng vo

Ngun cp

Transmitter lu lng

Chun ng ra

Ngun p sut

U NI

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KIM TRA 5 IM

Xc nh cc im cn hiu chun v tnh ton cc P tng ng

P thc cht l p sut PH t vo ng p sut cao do ng p sut thp thng vi kh quyn

Qu trnh kim tra v hiu chnh hon tonging vi cc trng hp khc.

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HiU CHUN DISPLACER LEVEL TRAMSITTER

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HiU CHUN DISPLACER LEVEL TRAMSITTER

Gm hai phn chnh: B phn th ch (displacer): t trong mt bnh cha Ngp trong cht lng cn o mc

B chuyn i (transmitter) c ni vi displacer thng qua

mt n by

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HIU CHUN DISPLACER LEVEL TRAMSITTER

B phn th ch (displacer): Khi lng thay i khi mc cht lng thay i Khi lng ln nht khi mc cht lng thp

hn im thp nht ca n Khi lng nh nht khi ngp hon ton trong

cht lng B chuyn i (transmitter)

o khi lng ca displacer v chuyn ithnh tn hiu in u ra

Tn hiu in u ra t l thun vi mc chtlng trong bn

Di o: Bng vi chiu di ca displacer5/18/2015

HIU CHUN DISPLACER LEVEL TRAMSITTER

Khi mt vt c nhng vo cht lng, ditc dng ca lc y, khi lng ca vt sb gim i mt lng ng bng khi lngca th tch cht lng m vt chim ch.

Cng thc xc nh khi lng ca mt vt:m = d.v, trong y:m: khi lng ca vtd: khi lng ring ca vtv: th tch ca vt

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HIU CHUN DISPLACER LEVEL TRAMSITTER

Khi mt vt c nhng vo cht lng, ditc dng ca lc y, khi lng ca vt sb gim i mt lng ng bng khi lngca th tch cht lng m vt chim ch.

Cng thc xc nh khi lng ca mt vt:m = d.v, trong y:m: khi lng ca vtd: khi lng ring ca vtv: th tch ca vt

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HC NHIT K

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Kim tra bn ngoi Kim tra k thut Kim tra o lng

HIU CHUN NHIT K

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Cc mc tng t nh kim tra phn p kCh vic tng gim nhit Hiu chun nhit k cn thi gian tin hnh

tng i lu.

HIU CHUN NHIT K

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Ngun cp

Chun ng vo

Nhit k

Ngun to nhit

U NI

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U NI

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U NI

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ng h mV TC

Nhit k chun 1

Ngun nhit

Nhit k chun 2

HIU CHUN TC

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CHUN VO/RA

Nhit k chun 1 v TC cng c a vo khoang to nhit ca thit b to nhit

ng h mV o in p ra trn TC Nhit k chun 2 o nhit mi trng

ti u quy chiu. Gi tr ny dng b tn hiu ra ca TC

Cc chun ny phi c chnh xc v thang o ph hp

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KIM TRA 3 IM

TC khng th iu chnh, do ch kim tra v hiu chun

Thng ch thc hin kim tra 3 im:Nhit mi trngNhit gia thang oNhit gi tr trn ca thang o

Phi xc nh nhit mi trng trc khi a TC vo bn to nhit

nh gi chnh xc ca TC

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TNH TON B NHIT

Ghi li in p ch th trn ng h mV (tng ng vi nhit u o khi nhit mi trng cha c b v 0)

Tra bng tm mV tng ng vi nhit mi trng (c trn nhit k chun 2)

Cng hai gi tr trn ta c mV tng ng vi nhit u o khi nhit mi trng c b v 0

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KIM TRA HIU CHUN TC

Ch : Dy dn ko di ni TC vi ng h

o phi cng vt liu vi TC Cc yu t bt li nh hng n TC:

l S khng ng nht trong cu trc ca TC

l Tnh nguyn vn ca cc mi nil S r t nhin ca dy TC sau thi

gian di lm vic

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HIU CHUN RTD

m k RTDNhit k

chun

Ngun nhit

Vi RTD 3 dy hoc 4 dy, ta ni chung cc dy cng mu li khi ni vi m k

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CHUN VO RA

Nhit k chun v RTD cng c a vo khoang to nhit ca thit b to nhit

m k o in tr u ra ca RTD Cc chun ny phi c chnh xc v

thang o ph hp

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HC RTD KIM TRA 3 IM

RTD khng th iu chnh, do ch kim tra v hiu chun

Thng ch thc hin kim tra 3 im:l Nhit mi trngl Nhit gia thang ol Nhit gi tr trn ca thang o

Tnh ton chnh xc

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HC TT U VO TC U NI

Ngun cp

Chun ng vo

Ngun cp

Transmitternhit

Chun ng ra

Nhit (t bn to nhit

hoc t simulator)

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HC TT U VO TC U NI

CH : Nu dy TC c ni n transmitter th

u quy chiu nm transmitter Nu dng ngun pht mV thay TC th

ch cc tnh

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CHUN VO RA

Nu transmitter c ni n TC th chun vo l nhit k. Lc TC v nhit k c t chung vo bn nhit.

Nu dng ngun mV thay cho TC th chun vo l ngun pht mV

Chun ra l ng h mA Dng thm nhit k o nhit ti u

quy chiu dng vo tnh ton b nhit

5/18/2015

KIM TRA 5 IM

Xc nh 5 im kim tra (nhit u vo)

Xc nh in p tng ng vi 5 im nhit u vo ( b nhit)

Cp cc in p va tnh n u vo ca transmitter ln lt theo chiu tng ri chiu gim, ng thi ghi li gi tr u ra tng ng.

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TNH TON B NHIT

Dng bng tra TC tnh in p tng ng vi tng im o.

Dng bng tra TC tnh in p tng ng vi nhit u quy chiu.

Hiu s hai in p ny chnh l in p cp n ng vo transmitter cho im nhit ang xt.

Khi s dng calibrator cp thng tn hiu nhit th khng cn b nhit.

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20

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HC TT U VO RTD U NI

Ngun cp

Chun ng vo

Ngun cp

Transmitternhit

Chun ng ra

5/18/2015

CHUN VO RA V KIM TRA 5 IM

Chun vo l mt ngun pht tn hiuging nh tn hiu RTD tht

Chun ra l mt ng h mAKim tra 5 im: Vic kim tra 5 im c thc hin

ging nh trng hp hiu chuntransmitter thng thng khc.

5/18/2015

LOOP CHECK4-20mA signals (Conventional, HART)

Mc ch: Xc nhn cc tham s ng dng l

chnh xc (span, alarm set point)

5/18/2015

LOOP CHECK4-20mA signals (Conventional, HART)

Analog Input Ti field:

l Dng Hart m phng tn hiu vo: 0%, 50%, 100% of span

l Dng thit b m phng m phng tnhiu vo: 0%, 50%, 100% of span

Ti trm iu khin:l Xc nhn gi tr c ca h thng K

(Control graphics / Faceplate)l Xc nhn cc gi tr thit lp alarm (HH,

Hi, Lo, LL)

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LOOP CHECK4-20mA signals (Conventional, HART)

Analog Output Ti trm iu khin:

l M Control Faceplate. l Chuyn sang ch Manuall Xut tn hiu ra: 0%, 50%, 100% of span

Ti field:l Xc nhn tn hiu nhn: 4, 12, 20 mA.l Xc nhn tc ng i vi thit b cui

(nu c)

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21

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LOOP CHECK Digital Input/Output signals

Mc ch: Xc nhn cc gi tr alarm set-point l

chnh xc (0 or 1 to alarm)

5/18/2015

LOOP CHECK Digital Input/Output signals

Digital input Ti field:

l Tc ng vo thit b (v d switches level, pressure, temperature, flow, Remote/Local, Start/Stop, etc.) nu c.

Ti trm iu khin:l Xc nhn gi tr ch th ti h thng

(Control graphics / Faceplate)

5/18/2015

LOOP CHECK Digital Input/Output signals

Digital output Ti trm iu khin:

l M Control Faceplatel Xut tn hiu ra ng, m thit b cui

Ti field:l Xc nhn tn hiu in p nhn cl Xc nhn tc ng ca thit b cui.

5/18/2015