Nrog kev nce qib txuas ntxiv ntawm kev lag luam automation, PLCs tau dhau los ua ib feem tseem ceeb ntawm kev tswj hwm kev lag luam thiab tau siv dav hauv kev tsim khoom. Txawm li cas los xij, ntau tus engineers tsis paub meej txog lawv cov kev tu, kev daws teeb meem, thiab cov txheej txheem ua haujlwm. Kab lus no qhia txog qee qhov kev paub dhau los thiab cov lus qhia tau txais los ntawm kev siv PLCs, uas peb cia siab tias yuav ua haujlwm rau peb cov phooj ywg.
I. PLC Inputs thiab Outputs
Ib qho me me PLC hloov tau yooj yim tswj cov txheej txheem nyuaj. Dab tsi yog pom yog ob kab ntawm staggered input thiab output relay terminals, coj lub teeb qhia, thiab PLC serial tooj-ntau zoo li ib qho kev sib txuas nrog ntau tus pins. Yog tsis muaj kev sab laj txog daim duab schematic, leej twg sim daws qhov teeb meem ntawm lub cuab yeej yuav poob, thiab cov txheej txheem ntawm kev txheeb xyuas qhov txhaum yuav qeeb heev. Muab qhov teeb meem no, peb tau tsim ib lub rooj raws li cov hluav taws xob schematic thiab muab tso rau ntawm cov khoom siv tswj lub console lossis tswj txee. Cov lus no teev cov lej davhlau ya nyob twg rau txhua qhov PLC cov tswv yim thiab cov zis, nrog rau lawv cov cim hluav taws xob sib raug zoo thiab cov npe suav suav- zoo ib yam li cov lus piav qhia ua haujlwm ntawm tus pins ntawm kev sib koom ua ke.
Nrog rau lub rooj I/O no, cov neeg siv hluav taws xob uas nkag siab txog cov txheej txheem kev khiav hauj lwm lossis paub txog cov cuab yeej tus ntaiv daim duab tuaj yeem daws teeb meem. Txawm li cas los xij, rau cov neeg siv hluav taws xob uas tsis paub txog cov txheej txheem kev ua haujlwm thiab tsis tuaj yeem nyeem cov duab ntaiv, nws yog ib qho tsim nyog los tsim ib lub rooj ntxiv: PLC I / O Logic Function Table. Cov lus no ua tau zoo piav qhia txog kev sib raug zoo ntawm cov tswv yim circuits (triggering ntsiab thiab cov ntsiab lus txuam) thiab cov zis circuits (actuators) nyob rau hauv feem ntau cov txheej txheem khiav hauj lwm. Kev xyaum tau pom tias yog tias koj tuaj yeem txawj siv lub rooj sib tham I / O thiab I / O logic muaj nuj nqi, koj tuaj yeem daws teeb meem hluav taws xob tsis zoo nrog kev yooj yim, txawm tias tsis hais txog schematics.
II. Input Circuit Troubleshooting
Txhawm rau txiav txim siab seb puas yog ib qho kev tawm tswv yim tshwj xeeb- xws li lub pob khawm, txwv kev hloov pauv, lossis xaim- ua haujlwm zoo, nias lub pob khawm (lossis lwm yam kev sib cuag) thaum lub PLC yog siv rau (zoo dua nyob rau hauv lub xeev uas tsis yog- ua haujlwm los tiv thaiv kev ua kom cov khoom siv tsis xav tau). Qhov no yuav luv luv -circuit txuas PLC input davhlau ya nyob twg mus rau lub davhlau ya nyob twg. Yog tias lub teeb pom kev ntawm PLC cuam tshuam rau lub laub khawm illuminates, nws qhia tau hais tias lub laub khawm thiab nws cov xov hlau ua haujlwm ib txwm. Yog tias qhov taw qhia tsis teeb, lub laub khawm tuaj yeem ua yuam kev, tej zaum yuav muaj kev sib cuag tsis zoo hauv cov xaim, lossis lub voj voog yuav tawg.
III. Output Circuit Troubleshooting
Rau PLC cov ntsiab lus tso tawm (ntawm no tsuas yog xa mus rau relay outputs), yog tias lub teeb pom kev sib raug rau cov khoom siv hluav taws xob tsis teeb thaum lub PLC tau lees paub tias yuav ua haujlwm, qhov no qhia tau tias PLC cov tswv yim tawm tswv yim - tso zis logic muaj nuj nqi rau cov khoom siv hluav taws xob tsis tau txaus siab. Nyob rau hauv lwm yam lus, muaj ib tug txhaum nyob rau hauv lub input circuit; xyuas lub input circuit raws li tau piav saum toj no. Yog tias lub teeb pom kev sib raug tau qhib tab sis lub actuator (xws li lub solenoid valve lossis contactor) tsis ua haujlwm, ua ntej kos lub solenoid valve tswj lub zog thiab fuses. Txoj kev yooj yim tshaj plaws yog siv lub ntsuas hluav taws xob los ntsuas qhov dav dav dav ntawm qhov sib thooj PLC cov zis taw tes. Yog tias lub ntsuas hluav taws xob tsis teeb, tej zaum yuav muaj teeb meem ntawm lub hwj chim, xws li lub tshuab hluav taws xob. Yog tias lub ntsuas hluav taws xob teeb pom kev zoo, lub zog hluav taws xob yog qhov zoo, thiab cov khoom siv solenoid valve, contactor, lossis cov xaim tsis raug. Yog hais tias lub kaw lus tseem tsis ua hauj lwm ib txwm tom qab kev teeb meem ntawm lub solenoid valve, contactor, thiab thaiv, siv ib tug multimeter: txuas ib qho kev sojntsuam mus rau qhov sib thooj cov zis ntau lub davhlau ya nyob twg thiab lwm yam rau qhov sib thooj PLC cov zis taw tes. Yog hais tias lub solenoid valve tseem tsis ua haujlwm, qhov no qhia tau hais tias muaj teeb meem hauv cov khoom siv hluav taws xob.
Yog hais tias lub solenoid valve ua haujlwm ntawm lub sijhawm no, qhov teeb meem nyob nrog PLC cov zis taw tes. Txij li thaum lub ntsuas hluav taws xob qee zaum yuav muab cov ntawv nyeem tsis raug, lwm txoj hauv kev tuaj yeem siv rau kev tsom xam: teeb lub multimeter mus rau qhov ntsuas hluav taws xob thiab ntsuas qhov hluav taws xob ntawm PLC cov zis taw tes thiab lub davhlau ya nyob twg. Yog tias qhov hluav taws xob yog xoom lossis ze rau xoom, PLC cov zis taw tes yog qhov qub, thiab qhov txhaum nyob hauv qhov hluav taws xob peripheral. Yog tias qhov hluav taws xob siab, nws qhia tau hais tias qhov kev sib cuag ntawm lub davhlau ya nyob twg yog siab dhau thiab nws puas. Tsis tas li ntawd, yog tias qhov taw qhia lub teeb tsis teeb, tab sis qhov sib thooj solenoid valve, contactor, thiab lwm yam, ua haujlwm, qhov no yuav qhia tau tias lub davhlau ya nyob twg tau raug hlawv vim muaj overload lossis luv luv Circuit Court. Nyob rau hauv rooj plaub no, tshem tawm cov kab hluav taws xob sab nraud los ntawm cov khoom siv hluav taws xob thiab siv cov khoom siv multimeter rau qhov kev tiv thaiv ntau yam los ntsuas qhov kev tawm tsam ntawm cov khoom siv hluav taws xob thiab cov khoom siv dav dav. Yog tias qhov kev tiv thaiv qis, nws qhia tau tias qhov kev sib cuag yog faulty; Yog tias qhov kev tiv thaiv tsis kawg, nws qhia tau hais tias qhov kev sib cuag tsis zoo, thiab cov teeb pom kev sib raug zoo yog qhov teeb meem.
IV. Program Logic Deduction
Muaj ntau hom PLCs feem ntau siv hauv kev lag luam. Rau qis-PLCs kawg, cov lus qhia ntaiv yog qhov zoo sib xws; rau nruab nrab-rau- siab- qauv kawg, xws li S7-300, ntau cov kev pab cuam tau sau ua lus lus. Daim duab ntaiv uas siv tau yuav tsum suav nrog cov cim suav suav; txwv tsis pub, lawv nyuaj nyeem. Yog tias koj muaj kev nkag siab dav dav ntawm cov cuab yeej siv cov txheej txheem lossis cov txheej txheem ua haujlwm ua ntej kuaj tus ntaiv daim duab, nws yuav txhais tau yooj yim dua. Thaum ua qhov kev ntsuam xyuas hluav taws xob tsis raug, txoj kev rov qab taug qab- kuj tseem hu ua txoj kev rov qab- feem ntau yog siv. Qhov no suav nrog kev siv I / O cov lus sib tham los nrhiav PLC cov lus tso tawm relay sib raug rau qhov txhaum thiab tom qab ntawd taug qab cov kev sib raug zoo uas ua rau nws ua haujlwm. Kev paub qhia tau hais tias ib zaug ib qho teeb meem raug txheeb xyuas, qhov txhaum feem ntau tuaj yeem txiav txim siab, vim nws tsis tshua muaj rau ob lossis ntau lub ntsiab lus txhaum tshwm sim ib txhij ntawm ib lub cuab yeej.
Kev kuaj xyuas PLC ua haujlwm tsis zoo
Feem ntau hais lus, PLCs yog cov cuab yeej siv tau zoo heev nrog tus nqi qis heev; Txawm li cas los xij, lwm yam tseem ceeb tuaj yeem ua rau lawv ua haujlwm tsis zoo.
Ib qho kev sib txuas sib txuas nrog 220V fais fab mov muaj nws ob lub teeb liab input hu xov tooj sib koom 4-core cable nrog tus hloov 220V fais fab kab. Thaum qhov hloov pauv ua tsis tiav thiab tus kws kho hluav taws xob hloov nws, lawv yuam kev hloov pauv cov khoom siv hluav taws xob tsis zoo nrog cov khoom siv hluav taws xob sib txuas rau PLC. Qhov no ua rau peb PLC cov ntsiab lus nkag mus hlawv thaum lub zog rov qab los.
Nyob rau lwm lub sijhawm, corrosion ua rau tawg nyob rau hauv nruab nrab kab ntawm lub kaw lus fais fab transformer, uas ua rau 220V fais fab mov rau PLC tau nce mus rau 380V, uas hlawv tawm lub hwj chim module nyob rau hauv qab ntawm PLC. Thaum lub sij hawm kho tom qab, ib qho 380/220V cais tswj transformer tau ntxiv.
Ntawm Siemens S7-200 PLC, cov khoom siv dav dav rau cov khoom siv tau sau npe 1L, 2L, thiab lwm yam, thaum lub chaw ua haujlwm tau sau tseg tias yog AC L1 N. Lub +24V fais fab mov yog suav tias yog L + M. Qhov no tuaj yeem yooj yim ua rau tsis meej pem rau cov pib tshiab lossis cov uas tsis muaj kev paub dhau los. Yog tias L + M raug kho tsis raug raws li 220V fais fab mov terminals, PLC's 24V fais fab mov yuav raug puas tsuaj rau lub sijhawm siv hluav taws xob.
Qhov tshwm sim ntawm kev puas tsuaj rau PLC, CPU, lossis cov khoom zoo sib xws, lossis software runtime yuam kev, yog zero. PLC cov ntsiab lus nkag kuj tsis zoo li yuav raug puas tsuaj tshwj tsis yog tshwm sim los ntawm qhov siab -voltage intrusion. Cov kev sib txuas ib txwm qhib ntawm PLC tso zis relays muaj lub neej ua haujlwm ntev heev, yog tias tsis muaj luv luv Circuit Court nyob rau hauv lub peripheral load los yog tsim flaws ua rau lub load tam sim no ntau tshaj qhov ntsuas. Yog li ntawd, thaum daws teeb meem hluav taws xob tsis zoo, lub hom phiaj yuav tsum yog nyob rau hauv cov khoom siv hluav taws xob peripheral ntawm PLC. Tsis txhob cia li xav tias PLC hardware lossis program ua txhaum. Qhov no yog qhov tseem ceeb heev rau kev kho cov cuab yeej faulty sai sai thiab rov pib tsim khoom. Yog li ntawd, thaum daws teeb meem hluav taws xob tsis zoo hauv PLC tswj Circuit Court, lub hom phiaj yuav tsum tsis txhob nyob ntawm PLC nws tus kheej, tab sis yog nyob rau hauv cov khoom siv hluav taws xob peripheral hauv kev tswj xyuas Circuit Court.