Siemens LMV52.240B1 - Configuring Vfds for Use with the LMV52

TechnicalInstructions  LMVSeries
DocumentNo.LV5‐1000
Section5 Page8 SCCInc.
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2. Thestaticoutputpressureoftheblower(SP)variesbythesquareofthechangeinRPM:
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3. Therequiredbrakehorsepoweroftheblower(BHP)variesbythecubeofthechangeinRPM:
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Example:Ablowerspinningat1750RPMproduces10inWCofstaticpressure,4500CFMofflow,and
requires20BH
P.WhathappensiftheRPMisincrea
sedto2750RPM?
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Assumptions:Airdamperiswideopen,andsystemeffects(suchastherestrictionduetotheboiler's
heatexchanger,theburner’s diffuser,etc...)arenottakenintoaccount.
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Flow:  CFM(new
)=(2750/1750)*4500=7071CFM
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Pressure: SP(new)=(2750/1750)
2
*10=24.7inWC
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Power: BHP(new)=(2750/1750)
3
*20=78BHP
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ConfiguringVFDsforusewiththeLMV52
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ModernVFDstypicallyhavehundredsofparametersthatcanbesettotailortheVFDtoaspecific
application.Asmentionedearlier,therearealsoatleastahundreddifferentmanufacturersofVFDs,
eachofwhichhavetheirownuniqueparameterlist.Duetothesetwofa ctors,SCCInc.offerspre‐
programmedVFDsthatcanbepurchasedwiththeVFDparameterssetupforusewithanLMV52.
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IfaVFDforusewithanLMV52ispurchasedandpr
ogrammedindependently,thefollowingpointswill
serveasageneralguidelineforprogrammingtheVFDfortheLMV52application.Notethatthis
guidelineisnecessarilygeneralduetothevarietyofVFDs offeredinthemarketplace.
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1. IfaVectorVFDisused(rec
ommended),setthe"ControlMethod"toOpenLoopVectormodeor
equivalent.
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2. Thestoppingmethod(aftertherun/stopcontactisopened)shouldbesetto"CoasttoStop"tolet
themotorcoasttoastopafterpost‐purge.
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3. Reverseoperation(theabi
litytoreversethemotorwith an input)shouldbedisabled.
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4. ConfiguretheVFDtoacceptanexternalrun/stopsignalviathedrycontactontheLMV52.
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