变频器安装配线时有哪些注意事项?
1、在电源和变频器之间,通常要接入低压断路器与接触器,以便在发生故障时能迅速切断电源,同时便于安装修理。
2、变频器与电动机之间一般不允许接入接触器。
3、由于变频器具有电子热保护功能,一般情况下可以不接热继电器。
4、变频器输出侧不允许接电容器,也不允许接电容式单相电动机。
暂无解析
I_____thepartymuchmoreiftherehadn’tbeenquitesuchacrowdofpeoplethere.
Peoplewithdisabilitiescomprisealargepartofthepopulation.Itisestimatedthatover35millionAmericanshavephysical,mental,orotherdisabilities.Abouthalfofthesedisabilitiesare“developmental”,i.e.,theyoccurpriortotheindividual’stwenty-secondbirthday,oftenformgeneticconditions,andaresevereenoughtoeffectthreeormoreareasofdevelopment,suchasmobility,communication,employment,etc.Mostotherdisabilitiesareconsidered“adventitious”,i.e.,accidentalorcausedbyoutsideforces.
Priortothe20thcentury,onlyasmallpercentageofpeoplewithdisabilitiessurvivedforlong.Medicaltreatmentforthesedisabilitieswasunavailable.Advancementsinmedicineandsocialserviceshavecreatedaclimateinwhichpeoplewithdisabilitiescanexperttohavesuchbasicneedsasfood,shelter,andmedicaltreatment.Unfortunately,thesebasicareoftennotavailable.Civillibertiessuchastherighttovote,marry,getaneducation,andagainemploymenthavehistoricallybeendeniedonthebasicofdisability.
Inrecentdecades,thedisabilityrightsmovementhasbeenorganizedtoflightagainsttheseinfringements(侵害)ofcivilrights.Congressrespondedbypassingmajorlegislationrecognizingpeoplewithdisabilitiesasprotectedclassundercivilrightsstatutes.
Stilltoday,peoplewithdisabilitiesmustfighttolivetheirlivesindependently.ItisestimatedthatmorethanhalfofqualifiedAmericanswithdisabilitiesareunemployed,andamajorityofthosewhodoworkareunderemployed.Abouttwo-thirdsliveatorbelowtheofficialpovertylevel.
Significantbarriers,especiallyintransportationandpublicawareness,preventdisabledpeoplefromtakingpartinsociety.Forexample,whilenolongerprohibitedbylawfrommarrying,apersonwithnoaccesstotransportationiseffectivelyexcludedfromcommunityandsocialactivitieswhichmightleadtothedevelopmentoflong-termrelationships.
Itwillonlybewhenpublicattitudesadvanceasfaraslawsarethatdisabledpeoplewillbefullyabletotaketotheirrightplaceinsociety.
16.”developmental”disability.
A.developsveryslowlyovertimeB.iscausedforces
C.occursinyouthandaffectsdevelopmentD.isgettingmoreandmoresevere
17.Mostdisabledpeopleusedtodieearlybecause.
A.disabilitiesdestroyedmajorbodilyfunctionsB.theywerenotverywelllookedafter
C.medicaltechniqueswerenotavailableD.theyweretoopoortogetpropertreatment
18.Intheauthor’sopinion,toenablethedisabledpeopletotaketheirrightfulplaceinsociety,.
A.morelawsshouldbepassedB.publicattitudesshouldbechanged
C.governmentshouldprovidemoreaidsD.morepublicfacilitiesshouldbeactup
19.Whichofthefollowingcannotbeinferredfromthepassage?
A.Manydisabledpeoplemayremainsinglefortheirwholelife.
B.Thepublictendstolookdownuponthedisabledpeople.
C.Thedisabledpeoplefeelinferiortothosesurroundingthem.
D.Discriminatory(有差别的)lawspreventthedisabledfrommixingwithothers.
20.Thebesttitleforthispassagemightbe.
A.HandicapsofPeoplewithDisabilitiesB.TheDifficultiesoftheDisabled
C.TheCausesforDisabilitiesD.MedicalTreatmentsforDisabilities
PartIIVocabularyandStructure(共40小题,每小题1分,共40分)
Directions:Inthisparttherearefortyincompletesentences.Eachsentenceisfollowedbyfourchoices.ChoosetheonethatbestcompletesthesentenceandthenmarkyouranswerontheAnswerSheet.
21.It’sstillearlyinthemorning.Thereisn’tintheoffice.
A.anyoneB.everyoneC.nobodyD.anypeople
22.isnotknownwhattheydiscussedinthemeeting.
A.ThatB.HeC.ThisD.It
23.Yhesadnewsbrokeherandshehasbeengloomyeversince.
A.feelingsB.emotionsC.mindD.heart
24.Heismuchofagentlemantofight.
A.soB.asC.veryD.too
25.Notuntilthistermtorealizehowimportantthissubjectistohisfuturecareerasadiplomat.
A.hebeganB.hahasbegunC.didhebeginD.thathahasbegun
26.whowouldliketogoonthetripshouldputtheirnamesonthelist.
A.ThoseB.TheseC.SomebodyD.Theones
27.Abottleweighslessafterairistakenout,provesthatairhasweight.
A.weB.itC.whichD.what
28.Howlong?
A.yousupposediditlastB.doyousupposeitlasted
C.didyousupposeitlastD.yousupposeitlasted
29.Smmithhadsometroubletheman’saccent.
A.tounderstandB.understandingC.forunderstandingD.withunderstanding
30.Thenextfewdayscouldbeforthepeacenegotiation.
A.maximumB.practicalC.criticalD.urgent
31.Hequitealotwhenhewasyoung.
A.usedtotravelB.usedtotravelingC.wasusedtotravelD.wouldusedtotravel
32.Youmeyourtelephonenumberincasesomeonewantstocontactyou.
A.hadbettergiveB.hadbettergivenC.hadbettertogiveD.hadbettergave
33.MaryusedtotheroomwithLinda.
A.separateB.divideC.holdD.share
34.—Mustwehandinourexercise-booksnow?
—No,you.
A.mustn’tB.don’tC.needn’tD.can’t
35.Shepulledawayfromthewindowanyoneshouldseethem.
A.lestB.eventhoughC.unlessD.onlyif
36.Notahasbeenfoundsofarthatcanhelpthepolicefindthecriminal.
A.factB.clueC.symbolD.sign
37.Shewouldmakeateacherfarsuperiortheaverage.
A.overB.thanC.beyondD.to
38.Radioisdifferentfromtelevisioninitsendsandreceivespictures.
A.whichB.thatC.whatD.this
39.Tomandjackhavereturnedbutstudentsofthegrouphaven’tcomebackyet.
A.otherB.theothersC.othersD.another
40.Ithalfayearsincewetostudyinthisuniversity.
A.is;comeB.is;havecome
C.hasbeen;cameD.hasbeen;havecome
41.Thefactthatsomethingischeapdoesn’tmeanitisoflowquality.
A.necessarilyB.especiallyC.essentiallyD.practically
42.Theysetoffbycarandthenearesttown.
A.madeforB.madeafterC.madeoutD.madeto
43.Takethisbaggageandyoucanfindenoughroom.
A.putitwhichB.putitinwhich
C.putitatwhereD.putitwherever
44.Hedoesn’twantthathe’sgoingaway.
A..tobeknownB.himtobeknown
C.thattobeknownD.ittobeknown
45.Thenoisearoundwasterrible,butIhadtoit.
A.keepawayfromB.keepupwithC.livewithD.liveon
46.Hethathisguestswerebored,althoughtheywerelisteningpolitely.
A.impressedB.sensedC.inferredD.identified
47.OnSundaysIpreferathometoout.
A.tosay;goB.stay;goingC.staying;goingD.staying;go
48.I’dliketowritetohim,butwhat’sthe?Heneverwritesback.
A.significanceB.businessC.pointD.purpose
49.Therewereopinionsastothebestlocationforthenewschool.
A.disagreeingB.conflictingC.rejectingD.reverting
50.bythenewsofhisfather’sdeath,hecouldhardlyutteraword.
A.TobestunnedB.StunnedC.TostunD.Stunning
51.,we’dbettermakesomechangesintheplan.
A.ThatisthecaseB.Thatbeenthecase
C.ThattobethecaseD.Thatbeingthecase
52.Theyhaveequippedtheofficewiththebusinessmachines.
A.lastB.latterC.latestD.later
53.ThepolicefoundthatGeorgehadstillanotherofincome.
A.originB.sourceC.basisD.means
54.Anopen-mindedteacherdoesn’talwaysonesingleteachingmethod.
A.setasideB.takeoverC.takeonD.stickto
55.Muchtothestudent’s,theexamwaspostponed.
A.burdenB.concernC.reliefD.requirement
56.Childrennormallyfeelalotofabouttheirfirstdayatschool.
A.anxietyB.differenceC.feelingsD.trouble
57.Theweatherwashotthatshedecidedtohavethebarberherhairstyle.
A.rather;tochangeB.so;change
C.muchtoo;changeD.too;changed
58.Shemeetherformerinstructoronthebus.
A.delightedtoB.happenedtoC.pleasedtoD.tendedto
59.Justasnotwowordsaretrulysynonymousnotwodifferentexpressionscanmeanexactlythesamething.
A.ratherB.alsoC.yetD.so
60.Thenewengineer’ssuggestionswereintherevisedplan.
A.entitledB.engagedC.embodiedD.estimated
ThediscoveryoftheAntarcticnotonlyprovedoneofthemostinterestingofallgeographicaladventures,butcreatedwhatmightbecalled“theheroicageofAntarcticexploration”.Bytheirtremendousheroism,mensuchasShakleton,Scott,andAmundsencausedanewcontinenttoemergefromtheshadows,andyetthatheroicage,littlemorethanacenturyold,isalreadypassing.Modernscienceandinventionsarerevolutionizingtheendurance,futurejourneysintotheseicywasteswillprobablydependonmotorvehiclesequippedwithcaterpillartractionratherthanonthedogsthatearlierdiscoverersfoundsoinvaluableandhardlycomparable.
FewrealizethatthisAntarcticcontinentisalmostequalinsizetoSouthAmerica,andenormousfieldofworkawaitsgeographersandprospectors.Thecoastsofthiscontinentremaintobeaccuratelycharted,andthemapingofthewholeoftheinteriorpresentsaformidabletasktothecartographerswhoundertakethework.Oncetheirlaborsarecompleted,itwillbepossibletoprospectthevastnaturalresourceswhichscientistsbelievewillfurnishoneofthelargesttreasurehoardsofmetalsandmineralstheworldhasyetknown,andalmostinexhaustiblesourcesofcopper,coal,uranium,andmanyotheroreswillbecomeavailabletoman.SuchdiscoverieswillusherinaneraofpracticalexploitationoftheAntarcticwastes.
Thepolardarknesswhichhidesthiscontinentforthesixwintermonthswillbedefeatedbyhugebatteriesoflight,andmakepossibletheestablishingofair-fieldsforthefutureinter-continentalairservicesbymakingtheseareasaslightasday.Presentflyingrouteswillbecompletelychanged,fortheAntarcticrefuelingbaseswillmakeflightsfromAustraliatoSouthAmericacomparativelyeasyoverthe5,000milesjourney.
Theclimateisnotlikelytoofferaninsuperableproblem,fortheexplorerAdmiralByrdhasshownthattheclimateispossibleevenformencompletelyuntrainedforexpeditionsintothosefrozenwastes.Someofhispartiesweremenwhohadneverseensnowbefore,andyetherecordsthattheysurvivedtherigorsoftheAntarcticclimatecomfortably,sothat,providedthattheappropriateinstallationsaremade,wemayassumethathumanbeingsfromallcountriescouldlivetheresafely.Byrdevenaffirmsthatitisprobablythemosthealthyclimateintheworld,fortheintensecoldofthousandsofyearshassterilizethiscontinent,andrendereditabsolutelygermfree,withtheconsequencesthatordinaryandextraordinarysicknessanddiseasesfromwhichmansuffersinotherzoneswithdifferentclimatesarehereutterlyunknown.Thereexistnoproblemsofconservationandpreservationoffoodsupplies,forthelatterkeepindefinitelywithoutanysignsofdeterioration;itmayevenbethatlatergenerationswillcometoregardtheAntarcticasthenaturalstorehouseforthewholeworld.
Plansarealreadyonfoottosetuppermanentbasesontheshoresofthiscontinent,andwhatsofewyearsagowasregardedasa“deadcontinent”nowpromisestobeamostactivecenterofhumanlifeandendeavor.
1.WhendidmanbegintoexploretheAntarctic?
A.About100yearsago.
B.Inthiscentury.
C.Atthebeginningofthe19thcentury.
D.In1798.
2.Whatmusttheexplorersbe,eventhoughtheyhavemodernequipmentandtechniques?
A.Braveandtough
B.Stubbornandarrogant.
C.Well-likedandhumorous.
D.Stoutandsmart.
3.Themosthealthyclimateintheworldis___.
A.inSouthAmerica.
B.intheArcticRegion.
C.intheAntarcticContinent.
D.intheAtlanticOcean.
4.WhatkindofmetalsandmineralscanwefindintheAntarctic?
A.Magnetite,coalandores.
B.Copper,coalanduranium.
C.Silver,naturalgasanduranium.
D.Aluminum,copperandnaturalgas.
5.Whatisplannedforthecontinent?
A.Buildingdamsalongthecoasts.
B.Settingupseveralsummerresortsalongthecoasts.
C.Mappingthecoastandwholeterritory.
D.Settinguppermanentbasesonthecoasts.
Recentresearchhasclaimedthatanexcessofpositiveionsintheaircanhaveanilleffectonpeople’sphysicalorpsychologicalhealth.Whatarepositiveions?Well,theairisfullofions,electricallychargedparticles,andgenerallythereisaroughbalancebetweenthepositiveandthenegativecharged.Butsometimesthisbalancebecomesdisturbedandalargerproportionofpositiveionsarefound.Thishappensnaturallybeforethunderstorm,earthquakeswhenwindssuchastheMistral,HamsinorSharavareblowingincertaincountries.Oritcanbecausedbyabuild-upofstaticelectricityindoorsfromcarpetsorclothingmadeofman-madefibres,orfromTVsets,duplicatorsorcomputerdisplayscreens.
Whenalargenumberofpositiveionsarepresentintheairmanypeopleexperienceunpleasanteffectssuchasheadaches,fatigue,irritability,andsomesensitivepeoplesuffernauseaorevenmentaldisturbance.Animalsarealsoaffected,particularlybeforeearthquakes,snakeshavebeenobservedtocomeoutofhibernation,ratstofleefromtheirburrows,dogshowlandcatsjumpaboutunaccountably.ThishasledtheUSGeographicalSurveytofundanetworkofvolunteerstowatchanimalsinanefforttoforeseesuchdisastersbeforetheyhitvulnerableareassuchasCalifornia.
Conversely,whenlargenumbersofnegativeionsarepresent,thenpeoplehaveafeelingofwell-being.Naturalconditionsthatproducetheselargeamountsarenearthesea,closetowaterfallsorfountains,orinanyplacewherewaterissprayed,orformsaspray.Thisprobablyaccountsforthebeneficialeffectofaholidaybythesea,orinthemountainswithtumblingstreamsorwaterfalls.
Toincreasethesupplyofnegativeionsindoors,somescientistsrecommendtheuseofionisers:smallportablemachines,whichgeneratenegativeions.Theyclaimthationisersnotonlycleanandrefreshtheairbutalsoimprovethehealthofpeoplesensitivetoexcesspositiveions.Ofcourse,therearethedetractors,otherscientists,whodismisssuchclaimsandareskepticalaboutnegative/positiveionresearch.Thereforepeoplecanonlymakeuptheirownmindsbyobservingtheeffectsonthemselves,oronothers,ofanegativerichorpoorenvironment.Afterallitisdebatablewhetherdependingonseismicreadingstoanticipateearthquakesismoreeffectivethanwatchingthecat.
1.Whateffectdoesexceedingpositiveionizationhaveonsomepeople?
A.Theythinktheyareinsane.
B.Theyfeelratherbad-temperedandshort-fussed.
C.Theybecomeviolentlysick.
D.Theyaretootiredtodoanything.
2.Inaccordancewiththepassage,staticelectricitycanbecausedby___.
A.usinghome-madeelectricalgoods.
B.wearingclothesmadeofnaturalmaterials.
C.walkingonartificialfloorcoverings.
D.copyingTVprogramsonacomputer.
3.Ahighnegativeioncountislikelytobefound___.
A.nearapoundwithawaterpump.
B.closetoaslow-flowingriver.
C.highinsomebarrenmountains.
D.byarotatingwatersprinkler.
4.Whatkindofmachinecangeneratenegativeionsindoors?
A.Ionisers.
B.Air-conditioners.
C.Exhaust-fans
D.Vacuumpumps.
5.Somescientistsbelievethat___.
A.watchinganimalstoanticipateearthquakesismoreeffectivethandependingonseismography.
B.theunusualbehaviorofanimalscannotbetrusted.
C.neitherwatchingnorusingseismographsisreliable.
D.earthquake
Evenasagirl,_____tobeherlife,andtheateraudiencesweretobeherteachers.