Kev xaiv qhov ntsuas hluav taws xob tiv thaiv hluav taws xob (megohmmeter) tsis yog hais txog kev nrhiav qhov hluav taws xob siab tshaj plaws ntawm daim ntawv spec. Nws yog hais txog kev sib piv cov cuab yeej rau koj cov qauv kuaj, koj txoj kev kuaj mob, thiab qhov ntsuas hluav taws xob ntawm cov cuab yeej hauv kev sim. Tau txais ib qho ntawm qhov tsis ncaj ncees lawm thiab koj tau them nyiaj ntau dua rau kev muaj peev xwm koj yeej tsis siv - lossis qhov phem dua, khiav cov kev ntsuam xyuas uas zoo rau ntawm daim ntawv tab sis nco txog kev puas tsuaj tiag tiag.
Kauj Ruam 1: Txheeb xyuas cov qauv kuaj thiab cov khoom kuaj
Pib nrog qhov koj sim tiag tiag. Hauv kev saib xyuas lub zog, tib lub megohmmeter feem ntau suav nrog transformers, cables, motors, generators, switchgear, thiab insulators-tab sis txhua chav kawm muaj cov chav kawm sib txawv thiab kev lees paub.
Tom qab ntawd txiav txim siab seb qhov ntsuas twg koj xav tau:
IR (Insulation Resistance): lub hauv paus chaw nyeem ntawv ntawm 1 feeb - yuav tsum tau ua rau txhua txoj haujlwm.
DAR (Dielectric Absorption Ratio): piv qhov tsis kam ntawm 60 s vs 30 s (los yog 60 s vs 15 s ntawm qee cov qauv). Muaj txiaj ntsig rau kev kuaj xyuas lub cev muaj zog thaum qhov kev sim 10-feeb tsis ua haujlwm.
PI (Polarization Index): IR ntawm 10 min muab faib los ntawm IR ntawm 1 min. Raws li IEEE 43-2013, PI yog qhov kev soj ntsuam tob rau cov motors loj, lub tshuab hluav taws xob, thiab cov khoom siv sib hloov tseem ceeb. A PI Ntau dua lossis sib npaug rau 2.0 (Class B) lossis Ntau dua lossis sib npaug rau 2.5 (Class F) feem ntau qhia txog kev tiv thaiv kev noj qab haus huv; qhov tseem ceeb hauv qab daim ntawv pov thawj kev tshawb nrhiav.
Yog tias koj qhov kev ua haujlwm raug txwv rau kev lees paub ntawm vaj huam sib luag, IR ib leeg tuaj yeem txaus. Yog tias koj tswj hwm MV rotating tshuab lossis taug qab cov qauv rau kev saib xyuas kev kwv yees, xaiv tus ntsuas nrog DAR tsis siv neeg thiab PI suav- phau ntawv lej ntawm qhov chaw ua haujlwm caw qhov yuam kev.
Kauj Ruam 2: Sau peb yam khoom ua ntej - muag khoom
Ua ntej koj sib piv cov hom, sib sau ua ke:
Khoom npe - piv txwv li, 35 kV XLPE cable, 6.6 kV generator, 415 V lub cev muaj zog tswj chaw.
Cov khoom siv hluav taws xob ntsuas ntsuas - qhov nominal kev khiav hauj lwm voltage ntawm winding los yog circuit, tsis yog qhov ntsuas voltage.
Yuav tsum tau kuaj voltage - ua raws OEM cov lus qhia ua ntej; yog tias tsis muaj, siv kev lag luam kev lag luam.
| Cov khoom siv ntsuas voltage | Hom DC test voltage |
|---|---|
|
Hauv qab 1 kV |
500 V |
|
1 kV - 2.5 kV |
500 V – 1,000 V |
|
2.5 kV - 5 kV |
1,000 V – 2,500 V |
|
5 kV - 12 kV |
2,500 V – 5,000 V |
|
Tshaj 12 kV |
5,000 V – 10,000 V |
Feem ntau cov kev xaiv ua pawg ntawm 500 V, 2,500 V, 5 kV, thiab 10 kV. A 5 kV digital megohmmeter nrog cov kauj ruam xaiv tau (piv txwv li, 100 V txog 5,000 V) npog feem ntau cov nroj tsuag kev lag luam- motors, MV switchgear, thiab cov xaim xaim mus txog rau 11 kV chav kawm . 10 kV thiab 15 kV cov twj paj nruag yog rau HV loj transformers, EHV scales {1.
Kauj ruam 3: Sib piv specs rau daim ntawv thov
Tshaj li qhov hluav taws xob, plaub qhov ntsuas cais lub megohmmeter siv tau los ntawm lub txee dai khaub ncaws:
Kev tiv thaiv ntau yam: MV cov cuab yeej yuav nyeem hauv GΩ lossis TΩ thaum rwb thaiv tsev noj qab haus huv. Xyuas kom meej tias qhov ntau tshaj koj qhov kev lees txais yam tsawg kawg nkaus ntawm tsawg kawg yog 10 ×.
luv-circuit tam sim no: IEEE xyaum pom zoo> 1 mA nyob rau hauv load; adjustable tso zis (1-6 mA) pab nyob rau hauv loj capacitive specimens zoo li cable khiav.
Guard davhlau ya nyob twg: shunts nto to kom paub tseeb winding nyeem ntawm cov khoom qias neeg los yog av noo.
Kev ntsuam xyuas kev nyab xeeb: lees paub IEC 61010-1 kev ua raws cai thiab tsim nyog overvoltage qeb rau qhov chaw koj txuas cov coj.
Kuj tseem xav txog qhov muaj peev xwm tso tawm. Tom qab kuaj 5 kV lossis 10 kV, khaws cia lub zog hauv cable lossis winding yog qhov phom sij rau kev nyab xeeb - cov hluav taws xob tsis siv neeg lossis cov hluav taws xob ywj pheej tsis xaiv rau ntawm HV ua haujlwm.
Kauj ruam 4: Xaiv ib qho -voltage vs multi-voltage
Yog tias koj sim tsuas yog LV panels, 1 kV handheld yuav txaus. Yog tias koj pab neeg nthuav dav kev lag luam boards thiab MV motors, ntau -voltage megohmmeter (500 V / 1 kV / 2.5 kV / 5 kV hauv ib chav tsev) zam kev nqa ob lub twj paj nruag. Rau cov cuab yeej tshwj xeeb- dej- cov tshuab hluav taws xob txias, piv txwv li - cov qauv tsim tshwj xeeb xws li dej sab hauv- cov tshuab hluav taws xob txias IR testers yuav tsim nyog rau kev nqis peev.
Ib qho piv txwv
Kev ntsuas 6.6 kV ntsuas lub tshuab hluav taws xob stator: siv 5,000 V DC rau IEEE 43, khiav 10-feeb PI xeem, teev IR ntawm 1 min thiab 10 min, thiab sib piv nrog cov ntawv nyeem ua ntej ntawm qhov kub zoo sib xws. Ib chav xws li 5 kV rwb thaiv tsev tiv thaiv tester nrog built-in PI / DAR, theem voltage (SV) hom, thiab cov ntaub ntawv khaws cia ua haujlwm ua haujlwm hauv ib zaug.
Kev ntsuam xyuas 480 V lub cev muaj zog ntawm lub Hoobkas hauv pem teb: 500 V lossis 1,000 V DC nrog 60-thib ob DAR feem ntau txaus rau kev kuaj xyuas niaj hnub.
