Description
TheDLRO200-115isdesignedtocheckandmeasurecontactresistanceinhighvoltagecircuitbreakers,disconnectingswitches(isolators),busbarjoints,orforanylowresistancemeasurement.Thetestsetaccuratelymeasureresistancesrangingfrom0.1µ-ohmto1ohm,athighcurrents.
Thisversatileinstrumentcanprovidetestcurrentsfrom10ampsupto200amps,subjecttotheloadresistanceandsupplyvoltage.Forthoseapplicationsthatdemandasmoothdccurrent,theDLRO200-115hasextrafilteringontheoutputtoreducemainsfrequencyrippleandcandrive200ampsthroughatotalcurrentloopresistanceof11milliohms.ThefilteredoutputoftheDLRO200-115alsoeliminatesmagnetictransientsthatcouldinductivelytripabreaker’scontrol(busdifferentialrelay),ifleftinthetestcircuit.
TheuniquedesignallowstheweightandsizeoftheDLRO200-115tobekepttoaminimum;theinstrumentweighslessthan32lbs.(14.5kg).Thissmallsizeplusawater/dustingressratingofIP54makesthetestsetequallyathomeintheworkshop,ontheproductionfloororinthefield.
300setsofresultsmaybestoredinthetestset’son-boardmemoryforlaterdownloadtoaPCormaybeoutputteddirectlytoaprinterviatheRS232port.Youmayalsoaddnotestoanystoredresultbyusingtheon-boardalphanumerickeypad,therebymakinglateridentificationofresultseasiertodetermine.
Aswellasaddingnotestostoredresults,thealphanumerickeypadallowsyoutosetthetestcurrentdirectlybykeepinginthevaluerequired.TheDLRO200-115willcheckthecontinuityofthetestcircuit,andwillquicklyrampthetestcurrentuptothedesiredlevel.Thekeyboardisalsousedtosetupperandlowerlimitsfortheresultandtopreventtheuseofexcessivecurrentsbysettinganupperlimittotheallowabletestcurrent.
TheDLRO200-115usesafourterminalmeasurementtechniquetocanceltheresistanceofthetestleadsfromthemeasurement.Thetestsetoperatesinoneofthreemodes,whicharesimplyselectedfromtheon-screenmenu.
CONTINUOUSmodeisprovidedforuserswhowishtomonitoraresistanceoveraperiodoftime.Connectthetestleads,selectthetestcurrentandpresstheTESTbutton.TheDLRO200-115willpassacurrentcontinuously,andmeasuretheloadresistanceat2secondintervals,untilthetestbuttonispressedtostopthetestorthetestcircuitisinterrupted.
MeasuringindividualjointsinabusbarisagoodexampleoftheconveniencetobegainedbyusingAUTOmode.Thetwocurrentleadsareconnectedtotheendsofthebusbar.Theywillremainconnectedthereuntilalltestshavebeencompleted.Whenthevoltageleadsmakecontactacrossajoint,theDLRO200-115detectsthatallfourleadsareconnected,carriesoutatestandstops.WhenyoumovetothenextjointtheDLRO200-115detectsthealreadycompletedcircuitautomaticallyandcarriesoutthenexttest,andsoonuntilalljointshavebeentested.Theresultsmaybestoredautomaticallyandmayberecalledtothedisplayordownloadedforreview.