Ib txoj hauv kev los ntsuas cov khoom siv hluav taws xob chassis to nrog lub multimeter.
Yog hais tias cov hlau casing ntawm cov khoom siv hluav taws xob yog zoo insulated thiab ntseeg tau hauv av, yuav tsis muaj to. Txawm li cas los xij, qee zaum cov cuab yeej muaj cov rwb thaiv tsev tsis zoo lossis tsis muaj kev ntseeg siab hauv av (nws yog ib qho ntawm cov chaw tsim khoom siv los txuas hauv av xaim ntawm cov khoom siv ncaj qha rau cov hlau txau nrog cov hmoov yas). Ntawm lub casing), cov hlau casing yuav raug them rau lub sijhawm no, yog li peb tuaj yeem siv AC voltage ntau ntawm cov digital multimeter los ntsuas qhov voltage ntawm cov hlau casing thiab hauv av kom paub seb cov khoom puas los.
Thaum ntsuas, teeb lub digital multimeter mus rau AC 200V ntau yam, kov cov kev sim liab coj mus rau cov khoom siv, thiab qhov ntsuas dub ua rau hauv av. Yog hais tias lub multimeter qhia tau hais tias ib tug voltage ntawm ntau tshaj kaum tawm volts, nws txhais tau hais tias lub rwb thaiv tsev kev ua tau zoo ntawm cov cuab yeej tsis zoo heev, los yog lub grounding yog unreliable. . Yog tias qhov ntsuas hluav taws xob nce mus txog 100 volts, feem ntau koj yuav hnov mob hluav taws xob thaum koj kov cov hlau casing ntawm lub cuab yeej. Lub sijhawm no, peb tuaj yeem ntsuas qhov xau tam sim no dua. Teem lub multimeter mus rau AC 2mA (lossis 20mA) ntau yam, kov cov kev sim liab ua rau cov khoom siv, thiab qhov kev sim dub ua rau hauv av. Qhov tam sim no tso tawm tam sim no yog qhov xau tam sim no, thiab nws qhov loj yog feem ntau ntawm μA qib.
Yuav ua li cas siv ib tug multimeter los ntsuas qhov zoo ntawm peb-xaim sensor
Txuas lub sensor, 24V fais fab mov, thiab multimeter los tsim ib lub voj voog, thiab teeb lub multimeter rau DC qhov chaw. Cov xaim xiav txuas nrog lub hwj chim tsis zoo, cov xaim xim av txuas nrog cov khoom siv hluav taws xob zoo, cov hlau dub txuas nrog cov xim dub lossis xim liab cov hlau lead ntawm multimeter, thiab cov hlau lead seem txuas nrog qhov zoo lossis qhov tsis zoo. Terminal ntawm lub hwj chim mov.
Lub sijhawm no, thaum NPN lossis PNP sensor ua haujlwm, qhov ntsuas hluav taws xob ntsuas los ntawm multimeter yog lub zog hluav taws xob, uas yuav tsum yog 24VDC. Thaum qhov kev xeem seem ntawm cov multimeter txuas nrog lub davhlau ya nyob twg zoo ntawm lub hwj huam mov, thiab ib qho khoom nyob ze ntawm lub sensor, lub multimeter muaj 24V voltage zaub, qhia tias lub sensor yog NPN sensor thiab yog ib hom qhib. . Thaum tsis muaj khoom nyob ze, lub multimeter muaj 24V voltage zaub, qhia tias Nws yog NPN hom sensor thiab ib txwm kaw.
Yog hais tias qhov seem ntawm qhov ntsuas ntawm lub multimeter txuas nrog lub davhlau ya nyob twg tsis zoo ntawm lub hwj huam mov, thiab muaj ib qho khoom mus rau lub sensor, thiab lub multimeter muaj 24V voltage zaub, nws txhais tau hais tias lub sensor yog PNP hom sensor thiab yog ib qho khoom siv hluav taws xob. nquag qhib hom. Tsis muaj ib yam khoom mus txog lub sensor thiab multimeter muaj 24V voltage zaub. Nws qhia tau hais tias nws yog PNP hom sensor thiab nws yog ib txwm kaw hom.
Yog li ntawd, rau qhov teeb meem no, yog tias lub sensor siv tsis tuaj yeem pom lub cim, tib txoj kev ntseeg siab los txiav txim yog los ntawm kev ntsuas. Tab sis nco ntsoov, NPN sensor kuj yog qhov sib thooj hloov. Nws outputs lub teeb liab qis, uas yog tus ncej tsis zoo ntawm 24V fais fab mov. PNP sensor tso tawm lub teeb liab siab, uas yog tus ncej zoo ntawm 24V fais fab mov.
