Taw qhia
Sib nqus qib gaugesnyob txhua qhov chaw ntawm cov txheej txheem tank. Cov neeg ua haujlwm cia siab rau lawv kom pom meej, pom hauv zos tam sim no, tab sis cov pab pawg automation feem ntau ntaus snags thaum rub cov ntaub ntawv tib theem rov qab mus rau PLC, DCS lossis SCADA system. Feem ntau off-the-shelf magnetic level gauges tsuas yog muaj qhov taw qhia pom. Ib lub nkoj sib koom loj uas tsis muaj dab tsi ntau dua 4-20 mA analog lossis yooj yim reed hloov lub tswb tawm, uas txhais tau tias koj yuav tsum npaj koj txoj kev sib txuas digital ua ntej xaim pib.
Modbus thiab Profibus dominate fieldbus installation rau hom kev ntsuas tank. Modbus yog qhov yooj yim, pheej yig thiab yooj yim rau yob tawm rau retrofits lossis compact skids. Profibus, tshwj xeeb tshaj yog Profibus DP, tau pom dav thoob plaws European cov txheej txheem txuas ntxiv uas muaj qhov sib xws, kev kwv yees lub sijhawm tsheb npav tseem ceeb. Cov ntawv tshaj tawm no taug kev los ntawm koj txoj kev sib koom ua ke, kev xaiv kho vajtse, kev teeb tsa kev ua haujlwm thiab cov kev mob taub hau uas tshwm sim thaum ua haujlwm. Peb mam li npog cov khoom siv hauv digital transmitters, kev hloov pauv ntawm lub rooj vag, xaim kev coj ua zoo tshaj plaws, sau npe daim ntawv qhia thiab yuav ua li cas kom phim koj cov teeb tsa rau kev tswj vaj huam sib luag koj twb muaj lawm.
Ua ntej: Tshawb xyuas seb koj qhov ntsuas ntsuas qhov sib nqus qhov twg tiag txhawb nqa
Native digital transmitter vs cais raws tu qauv converterIb qho yooj yim magnetic qib ntsuasmuaj ntab thiab pom chamber, thiab qhov ntawd yog nws. Nws qhia tau hais tias theem hauv zos, tsis muaj cov khoom tso tawm digital. Yog tias koj xav tau kev sib txuas lus hauv tsheb npav, koj tau txais ob txoj hauv kev rau pem hauv ntej.
Txoj kev huv huv yog xaj lub ntsuas ntsuas ua ntej nrog rau kev sib xyaw ua ke tej thaj chaw deb transmitter module. Qhov no txuas ncaj qha mus rau lub ntsuas ntsuas chamber, taug qab txoj haujlwm ntab, thiab tuaj yeem ua lub Hoobkas teeb tsa rau Modbus RTU, Modbus TCP, lossis Profibus PA / DP ntawm kev thov. Qhov no txo qis kev xaim thiab txo cov ntsiab lus kho vajtse ntxiv uas tuaj yeem ua tsis tiav.
Qhov thib ob txoj kev siv ib tug standalone converter los yog rooj vag. Qhov no yog koj mus-rau thaum koj twb muaj gauges ntsia uas tsuas tso zis 4-20 mA analog teeb liab. Koj pub cov teeb liab analog ntawd rau hauv lub qhov rooj raws tu qauv, uas txhais nws mus rau Modbus lossis Profibus telegrams rau koj qhov kev tswj hwm. Txoj kev retrofit no ua haujlwm zoo rau cov chaw brownfield, tab sis nws ntxiv lwm lub cuab yeej koj yuav xav tau calibrate, validate thiab tswj lub sijhawm.
Paub qhov txawv ntawm Modbus RTU, Modbus TCP, Profibus DP thiab Profibus PA Modbus RTU khiav dhau shielded RS-485 twisted khub. Nws siv tus qauv kev xaiv tsa tus qhev, thiab yuav luag txhua qhov nruab nrab PLC thiab HMI txhawb nqa nws tawm ntawm lub thawv. Nws haum rau lub tank ua liaj ua teb, me me batch skids thiab tawg nyob rau hauv tej thaj chaw deb tso tsheb hlau luam zoo, txawm tias cable ntev thiab tsheb thauj mus los yuav tsum tau ceev faj npaj. Modbus TCP siv tib Modbus cov qauv sau npe dhau Ethernet, uas ua rau muaj kev nkag siab zoo thaum lub pob txha muaj Ethernet twb nyob ze ntawm koj thaj chaw tank.
Profibus faib ua ob hom sib txawv rau kev ua haujlwm. Profibus DP tuav kev sib txuas lus ceev nrog PLC I / O thiab cov khoom siv hauv teb, raug rau cov kab ntau lawm thiab cov txheej txheem ntim khoom. Profibus PA yog tsim rau cov txheej txheem tsim kev phom sij, nrog rau kev tsav tsheb npav hauv kev nyab xeeb. Lub Profibus PA-enabled magnetic level gauge tuaj yeem qhia tib seem fieldbus nrog rau lwm cov txheej txheem transmitters, ib qho txiaj ntsig loj hauv cov chaw tawg.
Tsis txhob sib tov cov no li casually. Profibus DP tus tswv yuav tsis tham ncaj qha rau Modbus RTU qhev, thiab rov ua dua, tshwj tsis yog tias koj ntxiv cov txheej txheem kev txhais lus.
Kev sib koom ua ke 1: Modbus Teeb rau Magnetic Level Gauges
Kho vajtse thiab xaim rau Modbus RTU Yog tias koj lub transmitter txhawb Modbus RTU, khiav tiv thaiv RS-485 twisted khub. Muab ob npaug rau-kos A thiab B teeb liab polarity - flipped A / B kab yog ib qho ntawm cov laj thawj saum toj kawg nkaus commissioning stalks. Haum 120-ohm termination resistors nkaus xwb ntawm ob lub cev qhov kawg ntawm lub tsheb npav, tsis yog ntawm txhua lub cuab yeej. Cov terminators ntxiv rub lub tsheb npav voltage thiab tsim random, ncua kev poob qis uas yog npau suav phem rau rov ua dua thaum kuaj.
Route Modbus cables deb ntawm VFD thaiv, siab tam sim no lub cev muaj zog thiab vuam circuits thaum twg los tau. Hauv av muaj peev xwm sib txawv ntawm lub tank sib txuas taw tes thiab tswj chav hauv av kuj ua rau kev nyeem ntawv tsis zoo, tsis paub tseeb. Galvanic cais ntawm lub transmitter los yog rooj vag sab feem ntau kho qhov no yam tsis muaj tearing tawm thiab reworking tag nrho lub site grounding tswvyim.
Modbus configuration thiab sau npe daim ntawv qhia Teeb tsa tus qhev chaw nyob, baud tus nqi, parity thiab nres cov khoom kom phim koj tus tswv Modbus. Txhua tus neeg muag khoom nteg tawm cov ntawv sau npe sib txawv, yog li rub phau ntawv transmitter ua ntej tsim koj daim ntawv teev npe PLC. Feem ntau cov sib nqus qib transmitters muab cov thawj theem nyeem ntawv rau hauv ib lossis ob daim ntawv tuav. Ntau tus kuj tseem xa cov ntaub ntawv ntxiv: tank kub, kuaj mob, float fault flags thiab saturation tswb.
Lo nrog kev ua haujlwm code 03 rau kev nyeem ntawv tuav cov npe hauv feem ntau. Scale tus nqi ntawm cov lej nyoos hauv koj PLC lossis HMI. Lub transmitter xa rov qab yog 16-ntsis lossis 32-ntsis suav suav, thiab koj siv qhov ntsuas qhov ntsuas kom hloov tus lej ntawd rau hauv millimeters, meters lossis tank ntim feem pua. Tsis txhob xauv qhov ntsuas qhov ntsuas hauv lub rooj vag tshwj tsis yog tias koj lub xaib cov qauv xav tau nws; khaws scaling hauv PLC ua rau yav tom ntej transmitter swaps deb yooj yim dua.
Modbus TCP sau ntawv rau cov txee-mounted tes hauj lwm Modbus TCP tshem tawm cov RS-485 txwv ntawm node suav thiab cable nyob deb, tab sis koj tseem xav tau cov khoom lag luam zoo huv si. Muab cov IP zoo li qub rau cov xa tawm thiab cov rooj vag, sau koj cov subnet routing, thiab siv cov kev tswj tswj nrog cov txheej txheem VLAN cais. Khaws tus nqi scan kom tsim nyog. Tank theem hloov maj mam, yog li 500 ms rau ib-thib ob qhov kev xaiv tsa yog ntau tshaj qhov txaus. Kev xaiv tsa nrawm dua tsuas yog pawg ntawm cov tsheb khiav tsis tsim nyog nrog xoom kev txhim kho rau koj qhov ntsuas.
Kev sib xyaw ua ke 2: Kev sib xyaw ua ke ntawm Profibus rau Magnetic Level Gauges
Native Profibus PA lossis DP transmitters Thaum kojmagnetic theem gauge transmitternkoj nrog kev txhawb nqa Profibus, tus neeg xa khoom yuav muab cov ntaub ntawv GSD. Cov ntaub ntawv no txhais cov cuab yeej yog tus kheej, muaj cov txheej txheem cov ntaub ntawv khoom, kev kuaj kab mob thiab DP lossis PA profiles nws txhawb nqa. Ntshuam GSD rau hauv koj lub cuab yeej PLC engineering - TIA Portal lossis SIMATIC Manager, piv txwv li - ua ntej sim ua daim ntawv qhia kho vajtse.
Profibus PA cov khoom siv txuas mus rau qhov kev nyab xeeb PA ntu ntawm PA txuas. Qhov txuas txuas txuas txuas rau PA tsheb npav rov qab mus rau Profibus DP tus tswv. Qhov no yog tus qauv layout rau tshuaj lom neeg thiab roj & roj tank ua liaj ua teb nyob rau hauv tej chaw muaj kev phom sij. Yog tias koj xaiv Profibus DP transmitter xwb, nws txuas ncaj qha rau DP lub cev siv tus qauv Profibus RS-485 cable.
Gateway-raws li Profibus kev koom ua ke rau Modbus-tsuas transmitters Ntau ntau ntawm magnetic theem transmitters tsuas yog muab Modbus RTU. Yog tias koj cov nroj tsuag khiav Profibus DP tswj network, ntxiv Modbus RTU rau Profibus DP rooj vag. Ntawm Modbus sab, lub rooj vag ua haujlwm ua tus tswv, xaiv cov ntsuas qib. Ntawm Profibus sab, nws zoo li tus qhev DP ib txwm rau koj PLC.
Cov ntaub ntawv qhia hauv lub rooj vag yog qhov uas feem ntau cov neeg koom ua ke txiav cov ces kaum. Koj txhais raws nraim qhov twg Modbus sau npe los ntawm qib ntsuas pub rau hauv qhov twg Profibus input bytes hauv lub rooj vag I / O thaiv. Mess up byte los yog sau npe xaj ntawm no, thiab koj lub PLC yuav nchuav tawm cov khib nyiab ntab-point qhov tseem ceeb txawm tias thaum lub tsheb npav teeb pom kev zoo. Ib txwm siv tau cov ntawv nyeem nrog lub cuab yeej saib xyuas lub npav ua ntej xa mus.
Profibus thaiv thiab txiav cov cai Siv cov kab liab liab raug cai Profibus rau DP ntu. Tig rau ntawm qhov kev txiav tawm ua ke tsuas yog ntawm ob qho kawg ntawm txhua ntu tsheb npav. Khaws cov ntawv luv luv; ntev kais kab qhia teeb liab xav txog. Bond cable shield kom raug ntawm chav tswj kawg, ua raws li koj lub xaib txoj kev npaj sib koom ua ke equipotential. Kev tiv thaiv tsis zoo thiab qhov muaj peev xwm ntab tau tsim cov kev ua tsis sib xws ntawm cov tsheb npav classic uas noj cov sij hawm daws teeb meem.
Step-by-Step Commissioning Workflow Bench-test thaum twg koj ua tau.
Fais fab lub transmitter ntawm nws tus kheej, txuas lub laptop nrog cov neeg muag khoom teeb tsa software lossis Modbus cov cuab yeej pov npav, thiab lees paub cov qib kev nyeem ntawv ruaj khov ua ntej muab tso rau ntawm lub tank. Qhov no ntes cov chaw nyob phem, tsis sib haum xeeb baud chaw lossis DOA kho vajtse ua ntej koj nce lub tank lossis rub cov hlua tshiab.
Thaum lub cev tau teeb tsa, kaw tag nrho cov npav npav: tus qhev chaw nyob, baud, parity, Profibus chaw nres tsheb naj npawb thiab lub sijhawm saib xyuas. Thawb cov ntaub ntawv GSD rau Profibus kho vajtse thiab sau koj cov khoom siv kho vajtse. Rub tawm mus rau PLC thiab khaws lub qhov muag ntawm cov chaw kuaj xyuas tsheb npav. Saib rau kev rov ua dua, thav duab yuam kev lossis cov tub qhe poob ua ntej ua kom tsis siv neeg lub twj tso kua mis lossis valve tswj logic.
Calibrate theem ncua tawm tsam koj lub tank geometry. Txawm tias muaj kev sib kis digital tag nrho, qhov calibration sloppy yuav muab cov neeg ua haujlwm tsis raug thiab kev tswj tsis zoo.
Thaum kawg, nqa cov ntawv kuaj mob rau hauv koj li SCADA tswb pawg. Cov cuab yeej ua txhaum, cov chij float-stuck thiab lub tsheb npav saib xyuas txhua yam tsim nyog tau txais cov ntsiab lus ceeb toom. Lub ntsuas hluav taws xob sib nqus tuaj yeem poob kev taug qab yog tias lub ntab ntes tau, thiab lub tsheb npav yuav zoo siab rov qab nyeem ntawv kawg nkaus tshwj tsis yog lub transmitter xa me ntsis txhaum.
Common Integration Pitfalls kom zam tau
- Ua ntej, tsis txhob xav tias txhua qhov ntsuas qib sib nqus muaj cov zis digital. Standard units tsuas yog muab lub zos pom thiab reed hloov tswb ntsiab lus. Koj yuav tsum qhia qhov kev xaiv digital transmitter ntawm lub sijhawm txiav txim, lossis pob nyiaj siv rau lub converter tom qab.
- Thib ob, saib lub tsheb thauj khoom. RS-485 Modbus ntu muaj kev txwv nyuaj rau ntawm tus lej suav thiab ntev cable, thiab cov kev txwv ntawd txo qis ntawm tus nqi baud ntau dua. Kev thauj khoom ntau dhau ntawm lub cev nrog ntau lub tshuab xa hluav taws xob, ntsuas ntsuas thiab ntsuas ntsuas kub ua rau kev sib txuas lus tsis ruaj khov.
- Thib peb, byte thiab lo lus txiav txim tawg floating-point register nyeem tas li. Cov neeg muag khoom sib xyaw loj-endian thiab me-endian sau npe ntim. Yog tias koj tus nqi dhia ib ncig los yog nyeem raws li tus lej tsis zoo, sim byte swapping ua ntej ua ntej hloov kho vajtse.
- Thib plaub, tsis txhob saib xyuas kev ua raws li thaj chaw muaj kev phom sij. Yog tias lub tank zaum hauv thaj tsam Ex, koj lub tshuab xa hluav taws xob, lub rooj vag, cabling thiab fais fab mov tag nrho xav tau kev pom zoo zoo sib xws. Lub qhov rooj dav dav RS-485 yam tsis muaj ntawv pov thawj tsim nyog yuav tsis tuaj yeem nyob hauv thaj chaw raug cais.
Yuav Ua Li Cas Xaiv Ntawm Modbus thiab Profibus rau Koj Qhov Haujlwm
Xaiv Modbus RTU lossis Modbus TCP rau retrofits, me me tank ua liaj ua teb, dej skids los yog nqi-sensitive tsim. Nws raug nqi tsawg, ua haujlwm nrog ze li txhua lub cuab yeej, thiab feem ntau cov neeg koom ua ke tuaj yeem daws teeb meem sai sai.
Mus nrog Profibus thaum koj qhov chaw DCS lossis PLC tus qauv uas twb muaj lawm yog Profibus DP / PA, koj xav tau PA qhov kev nyab xeeb rau cov txheej txheem cais, lossis tus neeg siv kawg yuav tsum txiav txim siab lub sijhawm caij npav rau kev tswj cov txheej txheem txuas ntxiv. Profibus kho vajtse thiab engineering feem ntau khiav pricier, tab sis nws slots zoo nyob rau hauv tsim European txheej txheem cog architectures.
Yog tias koj khiav ib qho kev sib xyaw ua ke, lub rooj vag hloov dua siab tshiab ua haujlwm, tab sis kom meej meej cim qhov txhais lus ntawm koj cov duab hluav taws xob. Txhua lub rooj vag dhau los ua ib qho ntawm qhov tsis ua haujlwm, yog li tham los ntawm kev txwv tsis pub siv nrog cov neeg siv kawg rau kev nyab xeeb-tseem ceeb tanks.
Kaw Xav
Sib nqus qib gaugesxa cov pob zeb-khoom hauv zos pom qhov taw qhia, thiab lawv sib koom ua ke hauv kev tswj hwm digital yog tias koj daim ntawv qhia txog kev sib txuas ua ntej. Qhov kev txiav txim siab tseem ceeb yog seb koj puas tau hais qhia ib haiv neeg digital transmitter thaum xaj, lossis ntxiv lub rooj vag tom qab rau cov khoom lag luam uas twb muaj lawm. Modbus yog qhov hloov pauv tau, kev txhawb nqa dav dav. Profibus ci ntsa iab rau cov chaw uas twb tau khiav cov txheej txheem fieldbus, tshwj xeeb tshaj yog nyob rau hauv cov txheej txheem kev phom sij.
Siv sijhawm rau kev sim lub rooj ntev zaum, ua raws li cov kev cai txuas thiab txiav tawm kom zoo, daim ntawv sau npe daim ntawv qhia, thiab rub cov khoom tsis raug rau hauv koj qhov kev tswj hwm. Qhov kev saib xyuas me me no ua rau cov teeb meem tsheb npav yooj yim los ntawm snowballing mus rau hauv lub tank-theem downtime uas tsis tau npaj tseg. Thaum qhia txog qhov ntsuas tshiab, qhia koj tus qauv PLC raws tu qauv nrog tus neeg muag khoom thaum ntxov. Ua li ntawd, chav tsev ships pre-configured thiab npaj kom xa ncaj nraim mus rau koj lub tsheb npav network.
Cov ntaub ntawv
- IEC 61158 Kev sib txuas lus cov ntaub ntawv digital rau kev ntsuas thiab tswj - Fieldbus siv rau hauv kev tswj hwm kev lag luam (Profibus tus qauv)
- Lub Koom Haum Modbus, Modbus Application Protocol Specification V1.1b3
- IEC 61326-1 Cov khoom siv hluav taws xob rau kev ntsuas, tswj thiab siv chav kuaj - EMC cov cai
- PROFIBUS International, PROFIBUS PA Installation thiab Commissioning Guideline
- ISA-50.02, Fieldbus Standard for Measurement and Control
