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PCC-III MULTIPLE LOOP CONTROLLEROverview

• MultipleloopcontrollerLarge 160 block memory and 18 I/O points as astandard with three (3) additional I/O card slots foravailableexpansionupto31I/O.

• HighlyVisibleLEDDisplays- 10ProcessVariablesdisplayedwithEnglishlanguagedescription

- 10 Point (“first-out”) annunciator with Englishlanguage messages

- Large5.1",51segmentbargraphs

• Intuitive“Blockware”configurationlanguageCompletely configurable from controller front panel.Noexternalkeypadsorterminalsarerequiredforanyreason

• DualredundantmemorymodulesProtects configuration data, tuning parameters andoperatingstatusinformation

• OpticallyIsolatedRS485ModbusdatahighwayEnsuressafeandreliablecommunications

• 120VACDiscreteInput,RelayandTriacOutputBoilersystemcompatibilityand24VDCinternalpowersupply

• FlushMountedNEMA13FrontPanel

PCC-III Multiple Loop Controller

Reliable, FlexibleControl and Monitoring

The PCC-III Multiple Loop Controller is a boiler ormultiple loopprocess controller. The large I/Oquantity,integralOxygensensor,highlyvisiblefrontpanel,intuitive“Blockware”,redundantmemories,4-20mADCinputandoutputs, 120VACdiscrete contact inputs, isolated relayoutputs, 24VDC transmitter power supply, the ability tocontrol electric positioners directly and built-in industrystandard communications allows the PCC-III to be integratedintocomplexsystemswithaminimumnumberofexternalcomponents.ThePCC-IIIisacompletecontrolsolutionforindividualboilersormultiplecontrolloops.

User Friendly• EasyInstallation–ThePCC-IIIintegratesaflexible,

highly visible HMI, up to 31 I/O points (includingisolateddiscreteandanaloginputs,relayoutputsandtriacand4-20mADCoutputs),24VDCpowersuppliesand network communications into a single panelmountedNEMA13controller.

• Easy to operate - The PCC-III comes with largenumericandEnglishlanguagedisplays,pushbuttonsand intuitive bargraphswhich provide clear processinformation.A flexible display allows the operator toviewup to10different process variables, eachwithup to a 16 character English language descriptionmessage.The“first-in-first-out”annunciatorallowstheoperatortoviewtheorderofalarmsandacknowledgeeach separately. Configurable “lights and buttons”allow incorporation of auxiliary functions into thecontrollerwithouttheadditionofexternalhardware.

• Easy to configure - The PCC-III uses an intuitive“Blockware”configurationlanguage.Functions(AIN,PID, LOALM, F(x), etc) are simply copied into aconfiguration,andthenthecontrolsignalsare“wired”from block to block. Preferred’s innovative PC3_Draw™ forMSWindows®usesagraphical,“draganddrop”interface.BlockwarecanalsobeediteddirectlyfromthePCC-IIIfrontpanelorthespreadsheetstylePC3_Edit™. The PCC-III includes automated setuptoolstohelpreducecommissioningtimeandimprovecontrolsystemtuning.



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Safe Boiler OperationThePreferredPCC-IIIcontroller,joinedwithproperfuelandcombustionairflowregulatingelements,assuresaccurateandrepeatablecombustioncontrol.Fuelandairflowsarematchedinordertomaintainproperfueltoairratioatalltimes.Too littleaircausesunburned fuel lossesand toomuchair causesexcessive stack losses. Improper fuelair ratio can beDANGEROUS.Any combustion projectrequirestheassessmentofexistingpiping,burnerandboilerconditions, processmeasurements, analyzers, linkages,actuators,controlvalves,controldampersandoperationalrequirements.Preferred’sfocusoncombustionapplications,withthousandsofboilercontrolsysteminstallations,bringsthe required experience to the evaluation, developmentand commissioning of each project.With its redundantnon-volatilememories and “servicemanual”mode, thePCC-IIIControlleriscapableof“self-recovery”intheeventofasevere120VACelectricalpowerdisturbanceorsomeotheroccurrencethataltersdatainitsmemory.Moreover,an integraloptically isolatedRS485DataHighwayhelpspreventasinglecontrollerfailurefromdisruptinganentirenetwork.Lower Installed Cost Whenconsideringanycontroller,itisimportanttoconsiderthe total “installed” cost.ThePCC-III offers the lowestinstalled cost in the industry.Other controllers routinelyrequire external hardware such as interfacing relays,communicationisolators,24Vpowersupplies, laptopsorconfigurators and possibly extra controllers tomanagea specific application.ThePCC-III overcomesmany oftheseissuesbyincorporatingthesefeaturesintothebasiccontroller.ThePCC-III “Z” option card, as an example,eliminatestheneedforanexternalfluegasexcessoxygentransmitter,whilestandard120VACinputsand8Amprelayoutputs eliminate the need for interposing relays.Whilemostothercontrollersarewellover15"long,thecompactPCC-IIIfitseasilyintolessexpensive8"deepcabinetsorenclosures.

PCC-III MULTIPLE LOOP CONTROLLEROverview

Multiple Loops Duetoitsabilitytohandleseveralcontrolloops,applicationofasinglePCC-IIImayallowareductioninthetotalnumberofcontrollersnecessaryforaninstallation.Thelarge160functionblockconfigurationmemoryallowsanyfunctiontobeassignedtoeachblock,providingunequalledflexibilityandenoughpowertohandlejustaboutanyboilercontrolstrategy.Expandable I/OThewide variety ofPCC-III option boards allowone toexpandtheI/Ocapabilitiesofagivencontrollertofitanyapplication.Refertothespecificationspageforexpansioncardpossibilities.Upto15analoginputscanbeusedtosupportcomplexcontrolstrategiesorsatisfydataacquisitionneeds.ThePCC-III canbeequippedwith up to 6 relayoutputs.Theseoutputs are rated for up to 8A inductiveloadsandcanbeusedonmostapplicationswithoutexternal“helper”relays.Additionally,thePCC-IIIoffersTriacoutputstodrivereversibleACelectricactuators,solenoids,hornsandotherdevices.The“G”TriacOutputoptioncardincludesa“positionfeedback”potentiometeror4-20mADCinputsforclosedloopservopositioning.

3.75”

Panel Cutout Dimensionsand Minimum Spacings



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PCC-III MULTIPLE LOOP CONTROLLERApplications

RefertoEngineeringDataSectionforfeaturesandBenefitsofSinglePointPositioning,ParallelPositioningandFullyMeteredCombustionControlSystem.

PCC-III Multiple Loop Controller Example Applications:

Boiler Monitoring• FlueGasOxygenMonitoringwithASME“ByLosses”EfficiencyCalculationforOne(1)orTwo(2)Boilers• DataAcquisitionwithupto15AnalogInputsor13DigitalInputs

Header Temperature or Pressure Control• Two(2)orThree(3)BoilerModulatingLead/LagControl• PlantMasterModulatingControl

Single Point Positioning Combustion Control• FiringRateControl• FiringRateControlwithOxygenTrimControlusingLinkTrimActuator(LTA)orFuelTrimOutput• FiringRateControlwithDraftorDrumLevelControl

Parallel Positioning Combustion Control• FiringRateControl• FiringRateControlwithOxygenTrimControl• FiringRateControlwithOxygenTrimControlandVariableSpeedDrive(VSD)CombustionAirFanControl

Fully Metered Combustion Control• FiringRateControl• FiringRateControlwithOxygenTrimControl• FiringRateControlwithOxygenTrimControlandVariableSpeedDrive(VSD)CombustionAirFanControl

2ConfigurableLEDLights

4ConfigurablePushbuttonswithLEDLights

10ProcessVariableDisplayswith16CharacterEnglishLanguageDescription

10Point("first-out")Annunciatorwith16CharacterEnglishLanguageDescription

ACK-AcknowledgePushbuttonDIS -DisplaySelectionPushbutton

Increase,DecreasePushbuttons



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Combustion Control FeaturesCombustion isademandingprocesscontrolapplication.ThefollowingaresomeofthePCC-III featuresdevelopedtomeetthosedemands.

Multiple Function Generator F(x) blocksThe F(x) block is used to “characterize”or “curve fit” an analog signal by allowingeach value of the input to be assigned anindependentoutputvalue. ThePCC-III’s F(x)blockallows11breakpointstodefinetheinputvs.outputprofile.Theblocksareusedtosetupfeedforwardandremotesetpointsignalsaswellaslinearizerelationships.Forexample,incombustionairflowcontrolapplications,F(x)blocksareusedto“characterize”theAirFlowDemandsignal tocreateAirFlowControllerandOxygenTrimController setpoints.TheexampleshowntotherightusesseparateF(x)blocksto“characterize”differentsetpointsforgasandoilfiring.ThePCC-III hasthecapacitytouseasmanyF(x)functionsasarerequiredbytheapplication.

“Learn Mode” The PCC-III “Learn Mode” feature allowsmultipleF(x)blockinputvs.outputprofilestobe entered simultaneously.This capacity isbestdescribedwithanexample(refertotheexampleblockwarediagramatright).Duringcommissioning,thecontroltechnicianadjustsairandfuelflowsmanuallytoestablishoptimalfiring conditions for a particular load point.Withtheconditionsset,thetechniciansimplypressesthe“store”buttonforthePCC-III to store (learn) the current firing rate, oxygen valueandburnerair flow rate into theappropriateF(x) blocks simultaneously. This causesconsiderable time incommissioning,aswellasanoptimally“characterized”process.

Boiler Efficiency Function BlockTheboilerefficiencyfunctionallowsrealtimecalculationoftheboiler’sefficiencywithresultsdisplayedonthecontroller’sfrontpanel,recorderand/ordata acquisition system. Boiler efficiency is calculatedusingtheASME“bylosses”method.Thisfunctionrequiresinputsoffluegas temperature,combustion(ambient)airtemperature,percentoxygeninthefluegas,andpercentfiring rate toevaluate theefficiency. Notonlydoes thisfunctionhelpestablish“on-line”firedequipmentefficiency,but it also helps detect changes in efficiency, alertingoperating personnel of potentialmaintenance concernsbefore theybecomeaproblem.The resultsofefficiencycalculations can also be used in advanced controlapplications.

Simplified Blockware Diagram Exampleshowing the combustion air flow control and Oxygen trim portion of a full metering combustion control application

PCC-III MULTIPLE LOOP CONTROLLERConfiguration



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PCC-III MULTIPLE LOOP CONTROLLERConfiguration

Programmingconfigurationsisachallengingtaskformostprogrammablecontrollers.ThePCC-III multipleloopcontrolleristheexceptiontothisrulewiththreedifferentwaystocreateconfigurations.Configurationscanalwaysbemadedirectlyfromthefaceplateofthecontroller,usingthebuilt-ineditbuttons,butthetaskismadeeveneasierwithPreferred’sPC3_Edit™ and PC3_Draw™ software.BothprogramsallowtheusertodesignBlockwareconfigurationsandupload/download them to thePCC-III controller through thePC3-Link™ cable connecting the serial port of your computertoastandardRS232connectiononthePCC-III controller.PC3_Edit™ provides a straightforward spreadsheet styleinterfacewhilePC3_Draw™ usesapowerfulobject-orientedvisualinterface.BothprogramsarebuiltforMSWindows®.

PC3_Edit™The“pointandclick”simplicityofthePC3_Edit™softwaremakes“Blockware”configurationsimpleandintuitive.Theprogramusesastraightforwardspreadsheetformatwithaconvenientfill-in-the-blanksapproach.EachBlockhasanunlimitedlength“comments”fieldforcleardocumentation.The “Blockware” data and comments can be printed toanyMSWindows® compatible printer. The generatedconfigurationsaretheneasilydownloadedtothecontrollerthroughthePC3-Link™cable.

PC3_Draw™Thepowerfulobject-orientedCADinterfaceinPC3_Draw™makestheprogramtheidealchoiceforrapid“Blockware”programming in a visual environment. The program isbuilt on a Visio® platformwith extensive Visual Basicautomation.Standardfunctionsareincludedinmenusofpre-drawnfiguresforeachPCC-IIIBlockwarefunctiontype.Functionsaresimplydraggedontothedrawingpageandconnectedwith“smartconnector”linestointerconnecttheblocks.Blockinputsareautomaticallygeneratedbyplacingtheblockconnections.Doubleclickingonanyblockallowstheuser to edit datawithin theblock.Drawings canbeprintedonanyMSWindows®compatibleprinterorplotter.“Blockware”datacanalsobeprinted in thePC3_Edit™tabularformat.

Whatevertheconfigurationneeds,PreferredInstrumentshasaneasysolutionforyou.Whetherit’sthestraightforwardapproach of PC3_Edit™ or themore robust graphicalabilitiesofPC3_Draw™,configurationswillneverbethechoretheyusedtobe.

The PCC-III can be configured directly from the front panel or with Preferred’s PC3_Edit™ or PC3_Draw™ Software.

PC3_Draw™ uses a visual, “drag and drop” approach to “Blockware” design.

PC3_Edit™ Allows easy uploading, editing, and downloading of “Blockware” configurations.



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MechanicalCaseSize: 7.38"HX3.00"WX7.75"DEnclosureType: FlushpanelmountedFrontPanelSize: 8.00"HX3.75"WPanelCutout: 7.50"HX3.13"W(+/-.062)Weight: 6lbs.(excludingoptionboards)

EnvironmentalOperatingTemp: 32°to122°F(0°to50°C)StorageTemp: -20°to150°F(-28°to65°C)HumidityLimits: 15to95%(noncondensing)FrontPanel: NEMA13/IP65

PerformanceAccuracy: 0.025%AnalogInputsand

Outputs,70°FResolution: 16bitinput/16bitoutputMicroprocessor: 32bit,256kRAMExecutionCycle: TenpersecondNon-VolitaleMemoryLife: 10.8-30years,Blockware

dependent

Operator Control PanelDisplays:Alphanumeric: 8characterLED(0.2")

Numeric: 4.5digitLED(0.43")Bargraphs:PV&SP: 51segmentLED(5.1")Output: 21segmentLED(2.1")

Pushbuttons: Membrane,tactilefeedbackFaceplate: Mylar,splashproofAlarmAnnunciator: 10point,firstoutStatusIndicators: 6LED,configurableUserDefinedPushbuttons: 4configurable

ConfigurationLanguage: Functionblockstyle,

60functions,160BlocksSecurity: 4passwordlevels

RedundantmemoriesUserInterface:Faceplate: Fullyfrontfaceconfigurable

4dedicatedEDITkeyslocatedunderhingedcover

Laptop(optional): PC3_Edit™spreadsheetbasededitororPC3_Draw™graphical,object-orientededitor

CommunicationNetwork:Protocol: Modbus(ASCIIorRTUmode)Speed: 1200to38,400baudType: RS485,opticallyisolated

Configuration:Speed: 1200to38,400baudType: RS232withtelephonemodular

handsetconnector

Electrical InputPower: 120VAC(+/-15%)

BuiltinsurgesuppressorsInternalPowerSupplies: 24VDC@215mADC

(for2wiretransmitters)5VDC@50mADC(forpotentiometers)

Input/Output (Standard - no option cards)AnalogInputs: Quantity: 5

Type: 4-20mADC,0-5VDCAnalogOutputs: Quantity: 2

Type: 4-20mADC,750ohmloadDiscreteInputs: Quantity: 5

Type: 120VACopto-isolatedDiscreteOutputs:Quantity: 6

Type: (2) SPDTrelay,8A,120V(4) 24VDC,(sinking),100mA

Input/Output Option Cards OptionBoardA:AnalogInputs: Quantity: 5

Type: 4-20mADC,0-5VDC

OptionBoardF:AnalogInputs: Quantity: 3

Type: 4-20mADC,0-5VDCAnalogOutputs: Quantity: 2

Type: 4-20mADCOptionBoardG:TriacOutput: Quantity: 2pair

Type: 2A24-120VACAnalogInputs: Quantity: 2

Type: Pot/0-5VDC/4-20mADCOptionBoardJ:DigitalInputs: Quantity: 4

Type: 120VAC,Optically-IsolatedRelayOutputs: Quantity: 2

Type: Relaycontact,8AinductiveOptionBoardS:TriacOutput: Quantity: 1pair

Type: 2A24-120VACOptionBoardZ:AnalogInput: Quantity: 3

Type: 120VAC,Optically-IsolatedTriacOutput: Quantity: 1pair

Type: 2A-120VAC

PCC-III MULTIPLE LOOP CONTROLLERSpecifications



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Title Description CatalogNumber

PCC-IIIModelNumber

Plant Master (current outputs)

Includessteamheaderpressurecontrol.ThiscontrollermaybecombinedwithanyboilerSubmastercontrollertoformacompletesystem.

PC3-00003C PCC-III-0000

Plant Master with 3 Steam Boiler Lead/Lag

Includessteamheaderpressurecontrolandlead/lagsequencingforthreeboilers.ExternalleadboilerselectorswitchandBoilerSubmasterControllersarerequired.

PC3-10013C PCC-III-J000

Anumberofcommoncontrollerconfigurationscanbeorderedpre-programmedintothePCC-IIItoperformavarietyofdifferentcontrolfunctionsincluding:• PlantMaster• SinglePointPositioning(Jackshaft)BoilerMaster• ParallelPositioningBoilerMaster• FullyMeteredBoilerMaster• FeedwaterControl• Condensate Level Control• Stand-AloneOxygenAnalyzer

Note:althoughthecontrollersareprovidedpre-programmed,therewillstillbeadditionalfieldprogrammingrequiredtoentersite-specificdataintothecontrollersincluding:transmitterranges,customizedtextdescriptions,tuningparameters,etc.

Plant Master Configuration Options:


PCC-IIIModelNumber

Steam Boiler Submaster Jackshaft (current outputs)

Includesboilersteampressurecontrolforaboilerequippedwithajackshaft.Thisisacompletesystem. PC3-10103C PCC-III-0000

Steam Boiler Submaster Jackshaft (triac outputs)

Includesboilersteampressurecontrolforaboilerequippedwithajackshaft.Thisisacompletesystem. PC3-10013C PCC-III-G000

Hot Water Boiler Submaster Jackshaft

Includeshotwatergeneratortemperaturecontrolforahotwatergeneratorequippedwithajackshaft.Thisisacompletesystem.

PC3-10153C PCC-III-Z000

Oxygen Trim w/Efficiency Jackshaft (Z-board)

Includesoxygentrimlogicforajackshaft-equippedboiler.FueltrimequippedpressureregulatorandI/Pconverterarerequired.ConfigurationissetupforusewithPreferred’sZPOxygenAnalyzer.ThiscontrollermaybeusedasastandalonesystemorcombinedwithPC3-10103orPC3-10153toformacompletesystem.


Oxygen Trim w/Efficiency Jackshaft (Z-board)

Includesoxygentrimlogicforajackshaft-equippedboiler.Differentiallinktrimactuatorisrequired.ConfigurationissetupforusewithPreferred’sZPOxygenAnalyzer.Thiscontrollermaybeusedasastand-alonesystemorcombinedwithPC3-10103orPC3-10153toformacompletesystem.

PC3-10363TA PCC-III-ZG00

Boiler Submaster/ Draft, Jackshaft

Includesboilersteampressurecontrolanddraftdampercontrolforajackshaft-equippedboiler.Thisisacompletesystem.

PC3-12043C PCC-III-0G00

Single Point Positioning Boiler Master Configuration Options:

PCC-III MULTIPLE LOOP CONTROLLERStandardConfiguration



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PCC-III MULTIPLE LOOP CONTROLLERStandardConfiguration


PCC-IIIModelNumber

Boiler Submaster/ Fuel/Air Ratio, Parallel Positioning (no Oxygen Trim)

Includesboilersteampressurecontrolwithfuelvalve,air-fuelratiologicandairdampercontrolconfigurationforparallelpositioningfieldequipment.Thisisacompletesystem.

PC3-12053C PCC-III-0000

Parallel Positioning Boiler Master Configuration Options:


PCC-IIIModelNumber

Steam Boiler Submaster/ Fuel Flow, Full Metering

Includesboilersteampressurecontrolandone(1)fuelvalvecontrolconfiguredforfullymeteredfieldequipment.ThisconfigurationisusedwithPC3-12073C.

PC3-12033C PCC-III-0000

Air Flow/ Oxygen Trim, Full Metering

Includesair-fuelratiologic,airdampercontrolandoxygentrimlogicconfigurationforfullymeteredfieldequipment.ConfigurationissetupforusewithPreferred’sZPOxygenAnalyzer.ThisconfigurationisusedwithPC3-12033CorPC3-12493C.


Fully Metered Boiler Master Configuration Options:


PCC-IIIModelNumber

One Element Drum Level Feedwatervalvecontrolusingdrumlevelmeasurement. PC3-10213C PCC-III-0000

Two Element Drum Level Feedwatervalvecontrolusingsteamflowanddrumlevelmeasurements. PC3-10203C PCC-III-0000

Three Element Drum Level

Feedwatervalvecontrolusingsteamflow,drumlevelandfeedwaterflowmeasurements. PC3-10223C PCC-III-0000

Condensate Tank Level Condensatevalvecontrolwithcondensatelevelmeasurement. PC3-10263C PCC-III-0000

Deaerator Tank Level CondensateflowvalvecontrolwithDeaeratorlevelmeasurement. PC3-10273C PCC-III-0000

Oxygen Analyzer w/ Efficiency

Standaloneoxygenanalyzerconfiguration.ConfigurationissetupforusewithPreferred’sZPOxygenAnalyzer.


Standard PID Controller StandardPIDlogicwithhighandlowalarm. PC3-STDPID PCC-III-0000

Auxilliary Configuration Options:



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specifications subject to change without notice

PCC-III MULTIPLE LOOP CONTROLLEROrderingInformation

Option Card Slot #1:0 noneA AIN 5ch. 4-20mADC/0-5VDC

F AIN 3ch. 4-20mADC/0-5VDCAOUT 2ch. 4-20mADC CombinationBoard

G TOUT 2pair TriacOutputs,2A24-120VACAIN 2ch. Pot/0-5VDC/4-20mADC CombinationBoard

J DIN 4ch. 120VAC,OpticallyIsolatedDIN 2ch. RelayContact,8AInductive CombinationBoard

Z ZPOxygenAnalyzerAmplifierandStackTemperatureController

Option Card Slot #2Selectcardtypefromthe"Slot1"listabove

Option Card Slot #3

0 none

S TOUT 1pair TriacOutputs,2A24-120VAC

OptionalInput/OutputBoardExpansionExamples:

CatalogNumber:PCCIIIa b c 0

1. SpecifythePCC-IIIcatalognumberasshownbelow.2. Consultfactoryforpre-configuredcombustioncontrolstrategiesthatmaybeincludedforanadditionalcost.3. OptionallyspecifyPC3_Edit™orPC3_Draw™programmingpackages.4. Optionallyspecifythe“DCS-III”Controllerformonitoringapplications.The“DCS-III”isaPCC-IIIControllerwithout

faceplateandcase.Itissuppliedwithabracketformountingonanenclosuresubpanel.

PCC-III Model #4-20mADC0-5VDCAIN

4-20mADCAOUT

120VACDIN

8A(relay)ROUT

2A(triacpairs)TOUT

200mADC(sinking)DOUT

TotalI/O

PCC-III- 0 0 0 0 5 2 5 2 0 4 18PCC-III- A A 0 0 15 2 5 2 0 4 28PCC-III- F F 0 0 11 6 5 2 0 4 28PCC-III- J J 0 0 5 2 13 6 0 4 30PCC-III- G G S 0 9 2 5 2 5 4 27PCC-III- F G S 0 10 4 5 2 3 4 28PCC-III- A J 0 0 10 2 9 4 0 4 29

Note:Theexamplesgiveninnowayreflectthenumberofoptioncardpossibilities.ThePCC-III hasatotalofthree(3)optioncardslots,ofwhichoneisdesignatedforusebythe"S"cardonly.Theremainingtwoslotscanhouseanyoftheremainingoptioncardsinanydesiredcombination.



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PCC-III MULTIPLE LOOP CONTROLLERSuggestedSpecifications

1. GeneralSupplyamicroprocessor-basedmultipleloopcontrollersuitableforflushmountingonthefaceofacontrolpanel.Thecontrollershallprovideforbalanceless-bumplesstransfer.Innormaloperation,thisunitreceivesanaloginputs,calculatestheoutputandpositionstheassociatedfinalcontrolelement.Theoperatorcanmanuallyoverridethisfunctionbyselectingthemanualmodeofoperationandadjustingthefinalcontrolelement.Primaryoperatingvoltageshallbe120volts,60Hz,singlephase.Plug-infieldwiringshallallowremovalofthecontrollercircuitboardswithoutdisconnectinganypanelorfieldwiringfromtheterminalstrips.Thecontrollershall includeall necessary24VDCpower tosupply inputandoutputcircuits.2. EnclosureControllers shall be flushmountedon the control cabinet andshallhaveNEMA13rated(oil/waterspray)frontpaneldisplays,keyboard, cabinet to case and case to front panel gasketing.Controllersshallbeabletooperateindefinitelyin120°Flocationswithnocoolingfans.Controllertuningandconfigurationmenusshallbeconcealedbehindapanelfrontlocateddoor.3. Operator InterfaceDigitaldisplaysandkeypadshallbeprovidedon thecontrollerfrontpanel.Thecontrollershallbecapableofdisplayingupto10processvariableswithEnglishlanguagedescriptions.Additionally,controllersshallhavea tenpointEnglish language “first -out”annunciator.Controllers shall have two 50 segment red LEDbargraphs to locally display the process variable and setpointandone20segmentredLEDbargraphtodisplaytheoutput.Alloperatorpushbuttonsshallbeof themembranetypeandshallhavetactilefeedback.StatusindicationsshallbelonglifeLEDs.4. ConfigurationControl strategy shall not use“blockware” type language.Thecontrollershallbesuppliedwithanonboardlibraryof61analoganddiscretefunctionsandhaveaminimum160blockmemory.Anyquantityorcombinationoffunctionblocks(AIN,PID,LOALM,F(x),etc.)shallbeeasilycopiedintoacontrolstrategyand“wired”fromblocktoblock.ThecontrollershallbecapableofcalculatingrealtimeboilerefficiencybasedontheASME“bylosses”method.Thecalculationmustuserealtimeinputsofboilerfiringrate,fluegasoxygen, fluegas temperatureand fuel selected.Twosetsofadjustablefuelchemistrydataparametersshallbeincluded,andfiringratescaledradiationlossesshallbeusedformaximumaccuracy.Calculationsthatrelyonfixedconstantsormanuallyentered values for these conditions are not acceptable. Fuel/Airratiocurveandoxygentrimsetpointcurveadjustmentshallbeautomated for rapid, error-free burner setup.Only a singleoperator action shall be required to store commissioningdataintomultiple characterizer curves for a particular load point.“examine”and“blockforce”modesshallbeprovidedtoallowrapidsystemtroubleshooting.Eachcontrollershallbecompletelyfieldconfigurablefromthefrontpanelkeypadwithouttheuseofexternal

computersorhand-heldterminals.Configurationchanges,tuning,andoxygentrimsetpointcurveadjustmentshallbeaccomplishedviaakeypadonthecontrollerfrontpanel.Eachcontrollershallhaveseveral levelsofaccesssecurity topreventunauthorizedconfiguration.Provide laptopcomputer,software,andcables ifall formsof controllerconfigurationcannotbeperformed fromthecontrollerfaceplate.5. Input/ Output Signal TypesTheControllershalluse120VACfordiscreteinputsandoutputsforsystemcompatibility. Analoginputsshallbe1-5Vor4-20mADC.Analoginputandoutputsignalsshallbeisolatedfromearthground forground loopprevention.Thecontrollershall includeoptionalTRIAC,24-120VACsolidstateswitchoutputboardstodirectlyinterfacewithelectricactuators.ControllerI/Oquantitiesshallbeexpandablewithplug-inI/Ooptioncards.6. ReliabilityControl signals that are sharedbymultiple boilers (e.g.Plantmasterdemand,andRS485communicationslinks)shallhavesignal isolators in each boiler section. This is to prevent anequipmentorwiringfailureinoneboilerfromshuttingdownanyotherboiler.Eachtransmitterandsensorinputchannelshallhaveindividualpowersupplyshortcircuitprotection.Configurationandcalibrationdatashallbestoredinanon-volatileEEPROMplug-inmemorymodule.Inaddition,aredundantplug-inbackupmemorymoduleshallbefurnishedthatwillautomaticallydownload intothe primarymemory if primarymemory data is corrupted.Asanalternate toredundantplug-inmemorymodules,provideallnecessaryportablecomputers,softwareandhardwaretoallowconfigurationdownloadingandarchival.7. CommunicationEach controller shall be equipped with an isolated RS485communications data highway that communicates inModbusprotocol.IsolationisrequiredtopreventdamagetoallcontrollersonthesameRS485cableshoulda120VACshortoccuranywhereinthesystem.TheRS485protocolshallallow:Auto/Manualmodechange,setpointchange,variationofthemanualoutput,sensingandsilencingofalarms,changeofanyconfigurationparameter(includingPIDtuningconstants),changeoftimers,etc.Controllersshallnotdependonaserialcommunicationslinktosendsensordatarequiredfromcontrollertocontrollerunlessthelinkisfullyredundant.Provide all equipment capabilities specified in thisparagraph,evenifaconnectingSCADAsystemisnotincludedinthisproject.8. Quality AssuranceThecontrollersshallbemanufacturedandlabeledinaccordancewithUL508A (CSAC22.2#14 foruse inCanada). InspectionandlabelingshallbesupervisedbyULorotherOSHAapprovedNationallyRecognizedTestLab(NRTL).LackofanNRTLcertifiedUL508Awiringmethodsinspectionandlabelingwillbegroundsforcontrollerrejection.

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