IEC 61508 tus qauv kev nyab xeeb ua haujlwm tau ua rau lub neej yooj yim dua rau cov neeg tsim tshuab, nrog rau cov neeg siv kawg. Cov txiaj ntsig tau muaj kev nyab xeeb dua, ntse dua, me dua, yooj yim dua thiab ua haujlwm zoo dua.
Tshuab kev nyab xeeb tau hloov zuj zus txij li xyoo 1990s, nrog rau kev tso tawm ntawm cov qauv kev nyab xeeb ntawm IEC 61508 hauv xyoo 1998 uas yog ib qho kev hloov pauv rau cov neeg tsim tshuab thiab cov neeg siv kawg. Nrog rau lub tswv yim kev nyab xeeb tus qauv, cov khoom siv thiab cov neeg tsim tshuab tuaj yeem tsim kev ntseeg siab rau lawv cov neeg siv khoom tias lawv cov tshuab kev nyab xeeb tau raug sim thiab kuaj xyuas nruj, thiab cov neeg siv tsis tas yuav siv sijhawm thiab cov peev txheej los tshuaj xyuas qhov kev pheej hmoo ntawm lub tshuab lossis lub cev tsis ua haujlwm.
Kev taw qhia txog kev nyab xeeb ntawm kev ua haujlwm thiab cov qauv muaj feem xyuam kuj tseem (yuav luag) tso cov tshuab tsim tawm los ntawm kev ua haujlwm ntawm kev tsim qauv kev nyab xeeb, nrog rau kev yuav khoom, nruab, thiab txuas cov tsev txhab nyiaj ntawm cov khoom siv - xws li kev nyab xeeb contactors, relays, keyboards, IOs , thiab brake controllers – as well as the exhausting process of machine safety assessments and approval processes.
Yav dhau los, kev ua haujlwm ntawm lub tshuab muaj kev nyab xeeb tau ua tiav los ntawm kev siv cov relays uas txiav lub zog yog tias muaj kev nyab xeeb raug ua txhaum cai - xws li tus neeg teb xov tooj nkag mus rau hauv ib lub qhov rooj lossis tsoo lub teeb pom kev zoo. Kev nyab xeeb ua haujlwm tau hloov kho kho vajtse thiab cov txheej txheem kev pom zoo los ntawm software. Qhov tshwm sim tsis yog tsuas yog "kev ua haujlwm" kev nyab xeeb tiag tiag, tab sis kuj tseem nce lub sijhawm ua haujlwm, kev tsim khoom zoo dua, thiab txo qis rau cov neeg siv khoom kawg.
Tsis zoo li cov cuab yeej siv kev nyab xeeb raws li ib txwm siv, kev nyab xeeb kev ua haujlwm yog nyob ntawm cov khoom ntsuas kev nyab xeeb. Qhov sib txawv tseem ceeb yog tias tsis yog siv ntau yam kev nyab xeeb, feem ntau nws tuaj yeem ua ke rau hauv servo tsav, piv txwv li. Lub hom phiaj tseem ceeb yog los hloov cov khoom siv kev nyab xeeb feem ntau nrog software xws li Failsafe dhau EtherCat (FSoE). Qee qhov kho vajtse tseem xav tau - xws li kev ruaj ntseg nres, IO, thiab cov encoders - los tswj cov kev ua haujlwm ntawm cov khoom siv.
Tsis yog txiav fais fab tam sim ntawd mus rau ib qho axis yog tias qhov ntsuas kev nyab xeeb raug ua txhaum cai, kev ua haujlwm kev nyab xeeb txwv tsis pub txav ntawm lub axis. Qhov no tso cai rau lub kaw lus los daws qhov txhaum thaum tswj hwm qib kev nyab xeeb ua ntej thiab qhia rau tus neeg siv los ntawm kev kuaj tus kheej thiab kev ceeb toom tsis siv neeg.
Saib xyuas thiab teb
Tsav-raws li kev nyab xeeb ua haujlwm npog ntau yam haujlwm, los ntawm kev nyab xeeb ntawm kev tsav tsheb, mus rau kev soj ntsuam cov lus tsa suab xws li ceev, txoj hauj lwm, lossis lub zog. Kev nyab xeeb ua haujlwm ua ke hauv qee qhov servo drives suav nrog:
Safe Torque Off (STO). Qhov no tshem tawm lub zog rau lub cev muaj zog. Cov ncej txuas ntxiv mus rau lub freewheel yam tsis siv lub zog torque kom txog thaum lub zog kinetic khiav. Tus tsav tseem muaj zog kom rov pib dua sai dua. STO tuaj yeem qhib tau los ntawm ob lub teeb tsa kho vajtse lossis los ntawm kev sib txuas lus FSoE.
Safe Stop 1 (SS1). Active braking coj tus ncej mus rau qhov ceev, tswj nres kom lub axis nres tig. Lub sijhawm no, STO tau thov. SS1 yog siv qhov kev txav ntawm lub axis tuaj yeem ua rau muaj kev phom sij rau tib neeg lossis khoom siv.
Safe Operating Stop (SOS). Tus tsav tuav lub cev muaj zog ntawm xoom nrawm yam tsis tau tshem tawm torque. Cov khoom siv tuaj yeem rov pib dua tam sim yam tsis muaj kev pib dua.
Elmo's Platinum servo drives suav nrog kev nyab xeeb kev ua haujlwm thaum txo cov khoom siv kev nyab xeeb uas xav tau, nrog rau kev siv hluav taws xob, kev nyuaj, thiab cov nqi tshuab.
Safe Stop 2 (SS2). Tswj braking nqa high-kinetic-zog cov cuab yeej mus rau ib tug tswj nres, thaum lub sij hawm ntawd, SOS yog invoked. Nws yog siv thaum ntxiv cov lus tsa suab tuaj yeem ua rau muaj kev phom sij rau tib neeg, khoom lossis khoom siv.
Safe Brake Control (SBC). Qhov no muab kev ruaj ntseg tswj ntawm lub hwj chim tawm sab nraud, thiab feem ntau yog siv rau ntsug axes. Yog hais tias ib tug redundant braking system tsis ua hauj lwm, tus tsav feem ntau invokes SOS.
Safely Limited Speed (SLS). Qhov no teev qhov siab tshaj plaws ceev. Yog hais tias qhov kev ua txhaum ua rau lub kaw lus dhau ntawm tus nqi pib, tus tsav coj lub axis mus rau lub xeev muaj kev nyab xeeb.
Safely Limited Torque (SLT). Qhov no txwv lub cev muaj zog torque los ntawm kev txwv qhov tam sim no muab los ntawm tus tsav.
Safely Limited Position (SLP). Qhov no txwv lub hnab ntawv nyob rau hauv uas ib tug load yuav txav los ntawm kev saib xyuas nws txoj hauj lwm ntawm encoder tawm tswv yim. Yog tias qhov no qhia tias cov khoom thauj tau txav mus dhau lub hnab ntawv tso cai, nws raug tso tseg siv SS1 / STO lossis SS2 / SOS. Cov lus teb ceev ceev ntawm cov haujlwm no txo qis qhov kev nyab xeeb ntawm cov khoom siv.
Safe Input/Output. Rau servo drives nrog Safe I/O (xws li Elmo's Platinum series), ob hom kev nyab xeeb cov khoom siv tau txais kev txhawb nqa - cov tswv yim digital nrog cov zis ntsuas pulse rau kev kuaj mob, thiab cov tswv yim digital nrog OSSD (tso zis teeb liab hloov khoom siv) rau teeb meem teeb meem, lub teeb curtains thiab lwm yam. Kev nyab xeeb nres tso zis yog rau SIL3. Kev nyab xeeb cov tswv yim logic zoo ib yam li FSoE tswj, thiab kev nyab xeeb tso zis logic zoo ib yam li FSoE xwm txheej.