Dometic SmartStart III - General Information; Digital Inputs; Safety Inputs; Refrigerant Hi - High Side

4
AlarmButton
Thisbuttonwillflashredifthereisanactivealarm.Pressingthisbuttonwilltakeyoutotheactivealarmscreentodisplaythealarm.
Onceinthealarmscreen,usetheup/downbuttonstoscrollthroughalarms.TheAlarmscreencapturesasnapshotofthesystem
parametersatthe
timeofthefault.PressandholdtheAlarmbuttonfor3secondstocleartheactivealarmifthefaulthasbeen
corrected.
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GE NE RALINFORMATION 
TheDometicPLCcontrolsisamicrocontroller‐basedunitdesignedtocontrolmultiplechillers.Thisdesignallowstheuserflexibility
intheapplicationandimprovedcontrolsandprotection.ThePLCChillerusestemperaturedifferentialandhysteresistomanage
thecapacityofthechillerinsingleormultistageapplication.
Thechillersystemwillcomeprogrammedfromthefactorywiththeoptionsenabledforthatsystem.Althoughthesystemoffers
flexibility,theseoptionscanonlybeenabledbyafactoryrepresen tative.
TheuserwillbeabletoselectbetweenCool,HeatorElectricHeatmodeoperationinsinglestageconfigurationorIna
multistage
configuration.
ThePLCcontrollerisinte rnallygroundedwithisolationbetweeninputsandoutputs.Additionally,theoutputrelaysofferdouble
isolationsothatdifferentvoltagescanbeusedforgroupsofrelays.
Thesystemwillutilizevarioussensortypesformeasuringanalogtemperaturesandpressures.Fortemperaturemeasurements,the
systemwilluseNTCtype10K@77°thermistors.Pressuretransducersareratiometric0‐650PSI(45bar)rangeforbothsuctionand
dischargemonitoring.
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AvailableOptions:
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1. CompressorCurrentMonitoring
2. PumpCurrentMonitoring(SWandCW)
3. CondenserFreezeProtection
4. ElectricHeat
5. EEVControl
6. PressureTransducers
7. LoadSheddingInputSignal
8. LowCurrentAlarmtoindicateifsystemisnotactuallyrunningwhenenabled.(PumpsandCompressor)
9. Return
orSupplyWaterControl 
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DIGITAL IN PUTS 
Digitalinputsareusedtomonitorthestatusoftheprotectioncircuitsforthesystem.
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SAFETY I NP U T S 
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Alldiscreteinputswillbecheckedbeforethesystemwillbeenabled.Anyfaultsdetectedonstart‐upmustbeverifiedandcleared
viathePLCbeforesystemwillstartnormaloperation.
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FS– CHILLED WATER FLOW SWIT C H 
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WiththesystemineitherheatingorcoolingmodetheFlowswitchmustbeclosedpriortosystemstartingorastagebeingenabled.
InoperationifFlowislostformorethan10consecutiveseconds,thecompressororheatrelaywillbedisabled.Aflowswitchfault
willbe
recordedanddisplayed.
ACWFlowfaultwillberecordedandsystemwillbeinlockoutandamanualrestartwillberequired.ThePLCwillnotallowthecompressor
orelectricheatrelaytobeenergizedforthestagethathaslostfloworthewholesystemifacommonflowswitchisbeingused.
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FaultmustbemanuallyacknowledgedviathePLCandclearedpriortore‐enablingthesystemorstage.
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REFRIGERANT HI– HIGH SIDE PRESSURE L IM I T 
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ThePLCwillimmediatelyacknowledgeanopencircuitiftheHIpressureswitchistrippedandde‐energizethecompressor.Itwillrecord
anddisplayhighpressurefaultonthealarmscreen.IfthePLCdetectsahighpressurefaultduringoperation,aHPfaultwi llbedisplayed
andrecorded.
ThePLCwillnotallowthecompressorrelaytobere‐energized,un tilswitchisintheclosedposition.
ThefaultmustbemanuallyacknowledgedviathePLCandclearedpriortore ‐enablingthesystemorstage.
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