Yuav ua li cas txiav txim lub breakpoint ntawm hlau thiab cable los ntawm multimeter
Judging thaum lub core hlau tawg thiab shielding txheej yog tawg
Peb feem ntau siv digital multimeter, ntxiv rau kev ntsuas qhov ntsuas tsis zoo xws li voltage, tam sim no, tsis kam, capacitance thiab transistors, kuj tuaj yeem siv tau yooj yim los nthuav nws cov haujlwm thiab ua tiav lub hom phiaj ntawm ntau lub hom phiaj.
Yog li yuav ua li cas peb siv digital multimeter los txiav txim qhov tawg ntawm cov hlau thiab cable?
Thaum muaj kev cuam tshuam kev cuam tshuam hauv lub cable lossis cable, qhov tseeb qhov chaw ntawm qhov kev sib txuas tsis yog yooj yim los txiav txim siab vim qhov qhwv ntawm cov tawv nqaij rwb thaiv tsev. Qhov teeb meem no tuaj yeem daws tau yooj yim nrog lub digital multimeter.
Ib txoj hauv kev yog kev ntsuas kev tsis sib haum xeeb, uas feem ntau siv, tab sis teeb meem. Nws yog ib qho tsim nyog yuav tsum tau txiav lub cable tas li rau kev sim.
Qhov tseeb, muaj lwm txoj hauv kev: txuas ib kawg ntawm cov xaim (cable) nrog qhov tawg mus rau cov hlau nyob ntawm 220V mains, thiab tawm mus rau lwm qhov kawg hauv huab cua (ua tib zoo saib xyuas kev nyab xeeb yog qhov qhov tseem ceeb). Rub lub digital multimeter mus rau AC2V iav, pib los ntawm kev nkag mus rau qhov kawg ntawm cov xaim (cable), tuav lub nib ntawm cov hlau kuaj dub nrog ib txhais tes, thiab maj mam txav cov xim liab coj mus rau lub rwb thaiv tsev ntawm cov hlau nrog lub lwm yam tes, lub sij hawm no cov zaub qhia Cov nqi hluav taws xob tso tawm ntawm qhov screen yog hais txog 0.445V ( ntsuas los ntawm DT890D meter). Thaum tus cwj mem liab txav mus rau ib qho chaw, qhov hluav taws xob tso tawm ntawm cov khoom dheev poob mus rau 0.0 volts (kwv yees li ib feem kaum ntawm qhov qub voltage), thiab txog 15cm rau pem hauv ntej los ntawm txoj hauj lwm no (qhov nyob xaim nkag kawg) yog cov hlau ( cable) qhov twg lub breakpoint nyob.
Tab sis thaum siv txoj kev no los xyuas cov hlau thaiv, yog tias tsuas yog cov tub ntxhais hlau tawg tab sis cov txheej thaiv thaiv tsis tawg, ces txoj kev no tsis muaj zog.
Cov txheej txheem hauv qab no feem ntau yog siv rau kev sim ntawm cov cables.
Qhov tawg ntawm qhov yuam kev taw tes tuaj yeem tshawb pom los ntawm cov hauv qab no:
txoj kev induction
Muaj induction cwj mem thiab digital multimeter;
Haum rau cables tsis muaj hlau armor thiab steel daim kab xev shielding;
Ua tib zoo saib xyuas kom tsis txhob muaj hluav taws xob poob siab, qhov chaw sim thiab lub davhlau ya nyob twg uas lub davhlau ya nyob twg txuas nrog hluav taws xob thaum rewinding nrog cov khoom siv, thiab lwm yam.
cov txheej txheem tshwj xeeb:
1. Ncua tus neeg xyuas pib ntawm lub cable, thiab xyuas kom meej tias nws yuav tsis ua rau luv luv Circuit Court thiab hluav taws xob poob; Nyob rau tib lub sijhawm, xyuas kom meej tias cov cable nyob deb ntawm lub cev hauv av (xws li hauv av, khoom siv, thiab lwm yam) li sai tau;
2. Xaiv ib tug zoo insulating core nyob rau hauv lub cable, txuas rau 220VAC theem kab (nyob kab), thiab tsis hauv pem teb txoj kab;
3. Yog tias koj siv tus cwj mem hluav taws xob induction, kov cov inductive contacts ntawm tus cwj mem hluav taws xob nrog koj tus ntiv tes, thiab sim seb lub cwj mem hluav taws xob puas zoo li qub sab nraud ntawm cov txheej txheem insulating ntawm lub cev. Yog tias koj siv lub tshuab hluav taws xob digital, muab lub multimeter tso rau hauv 20 lossis 200mV ntau yam, muab lub tes tsho nyias nyias nyias ntawm cov hlau lead kuaj liab, thiab tuav cov ntawv xeem dub nrog koj txhais tes;
Kuaj sab nraum cov txheej insulating ntawm lub cev them, thiab nyeem; ces txav deb ntawm lub cev them, thiab nyeem; Sib piv qhov sib txawv ntawm ob qhov kev nyeem ntawv, feem ntau yuav tsum muaj kev nyeem ntawv siab dua ntawm lub cev them nyiaj, xws li {{0}}.4mV, thiab nyob deb ntawm lub cev them lub cev qis dua, xws li 0.15mV; nco ntsoov qhov no, koj tuaj yeem pib sim.
4. Kuaj raws lub cable ze ntawm lub cable. Thaum qhov taw qhia lub teeb ntawm induction cwj mem yog dimmed los yog nyeem ntawv ntawm lub multimeter tee pom tseeb, qhov hloov pauv yog qhov tawg.
5. Tom qab qhov kev xeem tiav lawm, ua tib zoo saib xyuas qhov tso tawm.
txoj kev capacitance
Thaum muaj txheej txheej hlau armor xws li tooj liab daim kab xev los yog steel daim kab xev sab nraum lub cable, txoj kev induction tsis tuaj yeem siv rau kev tshawb nrhiav, thiab txoj kev capacitance yog siv rau lub sijhawm no;
Haum rau tag nrho cov cables;
Thaum siv cov txheej txheem capacitance, ua ntej nkag siab txog lub hauv paus ntsiab lus ntawm kev ntsuas capacitance - thaum kuaj lub capacitance, AC / mem tes teeb liab yog siv nyob rau hauv lub xeem Circuit Court, uas yog, ntsuas lub AC ib feem ntawm lub voltage los yog them thiab tso tawm lub capacitor lub cev (ob tug sib nrig sib insulated hlau. ncej), txhawm rau kuaj cov hluav taws xob sib xyaw ntawm lub cev capacitor, thiab hloov mus rau hauv kev nyeem ntawv ntawm lub peev xwm.
Capacitance txoj kev, qhov tseeb tej zaum yuav cuam tshuam los ntawm inductance tsim los ntawm winding lub cable thiab cov rwb thaiv tsev cores ua ke, qhov tsis zoo ntawm conductors (xws li steel strips), thiab stray capacitance ntawm conductors; ntawm lawv Cov inductance tsawg heev thiab tuaj yeem tsis quav ntsej; qhov tsis kam muaj qhov cuam tshuam me ntsis ntawm kev ntsuas capacitance, tab sis qhov sib txawv ntawm kev sib txuas ntawm tus neeg xyuas pib thiab cov hlua hlau thiab qhov tsis sib txuas ntawm lub capacitance tsis loj, thiab nws tuaj yeem tsis quav ntsej; tab sis qhov stray capacitance muaj kev cuam tshuam ntau dua, thiab kev sim ua tiav. : Lub capacitance ntawm cov tub ntxhais tsis zoo thiab cov hlau sawb yog 117nF, thaum lwm cov cores txuas nrog steel sawb, qhov ntsuas tau tseem yog 117nF, thaum muaj 72nF ntawm ob lub cores.
Rau qhov yooj yim ntawm kev piav qhia, nws yog xav tias lub cable yog ib tug 2-core steel daim kab xev armored cable, ib tug ntawm uas muaj ib tug breakpoint;
Txoj kev tshwj xeeb yog raws li nram no:
1. Ncua tseg tag nrho cov tub ntxhais insulating conductors thiab armor khaubncaws sab nraud povtseg ntawm ob kawg ntawm lub cable;
2. Ntsuas qhov capacitance tus nqi ntawm cov tub ntxhais insulating tsis zoo thiab cov tub ntxhais uas puas lawm insulating rau steel sawb (los yog qhov thib peb zoo insulating core) ntawm ob qhov kawg, thiab sau tus nqi; nyob rau lub sijhawm no, qhov sib npaug ntawm ob qhov kawg ntawm cov tub ntxhais insulating tsis zoo raug ntsuas Cov peev txheej yuav tsum nyob ze heev; cov sum ntawm cov capacitance qhov tseem ceeb ntawm ob qho kawg ntawm tib lub cev tawg yuav tsum yog me ntsis ntau dua li qhov muaj peev xwm ntawm cov tub ntxhais insulating tsis zoo ntawm tib txoj hauj lwm, qhia tau hais tias tsuas muaj ib qho kev tawg, lossis ntau qhov kev sib cais tab sis nyob ze rau ib leeg; Yog tias ob qhov kawg ntawm tib lub cev tawg yog tias qhov sib npaug ntawm qhov muaj peev xwm muaj peev xwm tsawg dua li qhov muaj peev xwm ntawm cov tub ntxhais uas tsis muaj zog insulating ntawm tib txoj hauj lwm, nws txhais tau hais tias muaj tsawg kawg yog ob qhov tawg;
Nco tseg: Hauv txoj kev xav, yog tias tsuas muaj ib qho kev tawg lossis ntau qhov kev sib cais tab sis ze heev, cov txiaj ntsig ntawm qhov muaj peev xwm ntawm ob qho kawg yuav tsum ntau dua li qhov muaj peev xwm ntawm cov tub ntxhais insulating tsis zoo ntawm tib txoj haujlwm, thiab tus nqi sib txawv nrog qhov sib txawv. cables, saib theoretical tsom xam tom qab.
3. Raws li kev sib piv thiab kev suav ntawm tus nqi capacitance ntawm qhov tawg insulating core thiab cov tub ntxhais insulating tsis zoo, qhov ntev ntawm ob qhov kawg yog tau raws li qhov xav tau. Lub sijhawm no, qhov ntev yuav txawv ntawm qhov ntev, thiab cov kauj ruam tom ntej yog rov kho dua; tab sis ob-core unarmoured cable siv tsis tau. Ua kev kho.
4. Yog tias qhov sib npaug ntawm qhov ntsuas qhov ntev yog ntau dua qhov ntev ntawm qhov tseeb, tus nqi ntawm qhov ntev ntev yog qhov tsis zoo, thiab yog tias nws tsawg dua qhov ntev, nws yog qhov zoo; ces siv tus nqi capacitance ntawm cov tub ntxhais rwb thaiv tsev tawg los faib qhov sib txawv, thiab ntu ntev tau raug kho rau ntu ntev, ntu luv kho qhov ntu luv, thiab qhov tseeb ntawm qhov tawg tau txais.
