Specifications

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point,HVAC,andmode.Thethermostatcanrunonstand‐alonemanualmode,inwhichtheusersimply
usesthekeypad,ortheservercancontrolthethermostatwithuser‐definedscheduling.
WaterHeaterControlSubsystem
Lastyear’steamhadallottedwaterheatercontrolasasubsystemofthishomeautomationproject.
Althoughwewillnothavethetimeorresourcestocompletethisaspectoftheprojectthisyear,itwould
certainlymakeagreatadditioninafutureproject.Thewaterheatercontrolwouldfunctioninasimilar
fashionastheheatingandcoolinginthehouse.Itwouldacttomonitorandregulatetheoperation
scheduleofthewaterheatersothathomeresidentswouldn’tbewithouthotwaterbutwithoutthe
heaterconstantlyrunning.Theusercouldsetupaschedulethatincludedturningonbeforethemorning
sothatshowerscouldbehot.It’snotnecessarytokeepitrunningalldaywhileatwork,soitcouldbe
settopilot(standby)modeduringtheday.Thissubsystemwouldincludesensorsthatmonitorthe
intakeandoutflowtemperaturessothatanoptimalschedulecanbeautomate dbythesystem.
AccomplishedLastYear
Aspreviouslymentioned,thisprojectisacontinuationfromlastyear.Whilelastyear'steammade
significantprogress,theresultingprojectwasincompleteduesimplytotimeconstraints.Themain
accomplishmentfromlastyearwasthecontroloflightingandotherhomeappliancesusingthehome
controlserverovertheInsteonhomeautomationtechnology.
ThepreviousteamusedLinuxOSastheplatformtodevelopthehomecontrolserversoftware.The
softwareconsistsofthreedifferentlevels.Thehighestlevelisthewebuserinterfacewhichtiesallthe
systemcontrols.Thisisthewheretheuseraccessandmanagestheequipments.Thewebinterfaceis
alsoaccessiblefromanyPCwithaninternetconnection.Thesecondlevelis“IonBridge”whichisan
abstractinterfaceusetoreceivePLC(InsteonPowerLincV2)eventsandsendmessagestotheInsteon
devices.Thelowestlevelis“Ion”whichisbasicallythedriverlibraryforthePLC.Ionisanopensource
codeavailableonthewebandwasneveractuallyfinishedbyanyone.Theteammanagedtocomplete
thecodeandsuccessfullycompileittoworkwiththe“IonBridge”.
AUSBcablewasusedtoconnectthePLCwiththehomecontrolserver.TheindividualInsteonnodes
(whichcontro lthelightingandotherhomeappliances)wereconnectedtothePLCusingtwodifferent
signals;electricalphasesofthehome110VAClineandRF.ThereweredifferenttypesofInsteonnodes
used.ThefirstisSwitchLincwhichprovidescontroltoincandescentbulbs,low‐voltagehalogenand
fluorescentbulbsforupto32brightnesslevels.LampLinchasthesamefunctionalityasSwitchLincbutit
isusedforlampsinstead.TheApplianceLincprovides controltohomeappliancesandcanonlybe
programmabletoon/offcommand.
Inordertodemonstratethefunctionalityoftheequipmentsduringdesignday,thepreviousteam
constructedamodelhomecircuitryboard.Thereweretwo maincircuits.Thefirstcircuitconsistsof
SwitchLincs,ApplianceLincsandpoweroutlets.ThesecondcircuitconsistsofLampLincsandalsopower
outlets.TheSwitchLincsis supposedtorepresentthelightingcircuit.Alltheotherlincsandpower
outletsrepresentthehouseelectricalwiring.TwoRFsignalenhancerswereusedtoincreasetheRF
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