Siemens LMV5 Series Technical Instructions

LMVSeriesTechnicalInstructions 
DocumentNo.LV5‐1000
SCCInc. Page9 Section5
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5. TheVFDshouldbeabletodoa"flyingstart"sothattheVFDwillnottrytostopafree‐wheeling
blowerwheelbeforestartingthewheelspinningagain.Blowerwheelsfrequentlyfree‐wheeldueto
draftandotherfactors.

6. Ramptimes‐theVFDshouldbesettoslightlyfasterramptimescomparedtotheLMV52ramp
times(LMV52parametersTimeNoFlameandOperatRampMod).Ifth
eshorterLMV52ramptimeis
setto60seconds,therampupandrampdowntimesintheVFDshouldbesetnolongerthan55
seconds.Ingeneral,a5seconddifferentialwillworkwellinmostsituations.
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Note:Ifshortramptimesarenecessarywithlarge
blowers(heavyblowerwheels),abraking
resistormaybenecessary.Seethebrakingresistorexplanationonthepreviouspages.

7. Rampsmust belinearwiththe4‐20mAsignal.S‐shapedrampsandPID/filteringonthe4‐20mA
signalwillcausespeedfa ultsontheLMV52.
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8. Theanalogsignalshouldbeconfigured fora4‐
20mAsignalanditshouldbespannedsothat4mA=
0Hzand20mA=62Hz(forblowersdesignedfor60Hzpower).Theadditional2Hzistomakesure
thatfullblowerspeedisachievableevenwitha19.5mAstandardization(seestandardizatio
n
sectionbelow).
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9. ThemotornameplatedatamustbeenteredforthemotorthattheVFDisconnectedto.
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10. SomeVFDshaveafeaturethatwillstoprampingthedriveifacriti
callimitinthedriveis
approached.OnsomeVFDs,thisfeatureisreferredtoas"stallprevention".Twocom
monlimitsare
themaximumamperagedrawnandtheDCbusvoltage.Stallprevention,whileprotectingthedrive,
cancausespeedfaultswiththeLMV52duetothedriveceasingtorampinconcertwiththeLMV52.
Ifabrakingresistorisused,stallpreventioncantypicallybedea
ctivated.
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11. ForVectorVFDs,performatleastastaticauto‐tunesothattheVFD"learns"thecharacteristicsof
themotoritisconnectedto.Astaticauto‐tunedoes notrequirethattheload(blowerwheel)be
disconnectedsincetheloadisnotspun.Somedynamicaut
o‐tunesrequirethattheloadis
disconnected.
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12. Ifabrakingresistorisbeingused,thebrakingresistorwilltypicallyhaveahightemperatureswitch.
Thedriveshouldbeprogrammedandwiredsothatabrakingresistorovertemperaturewillcause
thedrivetoshutdown.
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StandardizingtheLMV52
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AftertheLMV52,VFD,blower,andspeedsensorareinstalledandwiredcorrectly(seeSection2),and
theVFDparametersaresetcorrectly,theLMV52mustbestandardized.
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Thisonlyneedstobedoneonce,aslongastherearenotchangestotheVFDand/orblower.Ifany
changesaremade(includingVFDprogramming),itisrec
ommendedtore‐standardizesothattheLMV52
can"learn"thechangethatwasmade.
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Siemens LMV5 Series Specifications

General

Brand	Siemens
Model	LMV5 Series
Category	Control Systems
Language	English