BURNERMATE UNIVERSAL BOILER CONTROLLER Overview Instruments/Cont… · Boiler Control Functions Many of the most common boiler control functions are incorporated in the BMU. This

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Instruments & Controls

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BURNERMATE UNIVERSAL BOILER CONTROLLER Overview

The BurnerMate Universal offerscompleteboilercontrolinaneconomic,off-the-shelf,pre-programmedcontroller.Separate processors are used for flame safeguard andcombustioncontrolforNFPA85compliance.ConfigurationisdoneinthefieldusingtheLCDkeypad,theoptionaltouchscreen,orourexclusiveBMU_EditsoftwareonyourPC.BMUfunctionsinclude:

• Advancedflamesafeguardcontrol includingfirstoutannunciation, nuisance trip protection, and lockoutsnapshot

• Combustioncontrol(jackshaft,parallelpositioning,withoptionaloxygentrim)usinguptotenservosanduptofourVariableSpeedDrives(VSDs)

• Draftcontrol• Feedwater control: single, two-element, or three-

element.• Large 10” color touch screenwith pre-programmed

graphicpages

The BurnerMateUniversal is available for immediatedelivery,requiresnoprogramming,and isrecognizedbyU.L.

AdvancedFlameSafeguardControlTheBurnerMateUniversaltakesburnersafetytoahigherlevel.Insteadofonedigital inputprovingtheboilerlimitsaremade, theBMUaccepts over forty boiler limits intoseparatedigital inputs.Thismakesfirstoutannunciationeasy,aswellasadvanceddiagnosticstoquicklypinpointwhyaboilertrippedandwhatneedstobedonetobringitonlineagain.Oneortwoflamescannerscanbeusedforaddedreliability,or increasedboilersafety.Flamesafetycontrolfeaturesinclude:

• Supportforuptothreefuels(oil,naturalgas,andasecondgasfuel).

• Fuel changeover canbe initiated locallyor remotelyeithershuttingdowntheboilerduringthefuelchange,orchangingfuel“on-the-fly”.Fuelchangecanbeinitiatedmanually,orremotelyviacontactsorModbus

• Monitorsuptoninerecyclinglimits,upto33shutdownlimitsandoneortwoflamescanners.

• Alllimitinputsare120VAC,wiredinparallel,andseparatelyannunciated

• Duringashutdown,allmajorstatusbitsarerecordedandsavedforuptothelast10lockouts.

• Adjustabletimedelaysareavailableformanylimitstoavoidtrips

• Gasvalve leak test logiccanbeconfigured (withorwithoutaventvalve)

• Automateddailylowwatercutoutblowdownwithlevelswitchtestcanbeconfiguredtoalarmorshutdowntheburnerifafaultylowwatercutoutswitchisdetected.

• Optionaloilgunpurgelogiccanbeconfigured(blow-throughintothefurnace,orsuctionedbackoutofthegunviascavengerpump)

• High fluegas temperature shutdown is included foradditionaldryboilerprotection

• Toreducecombustiblesinthefurnace,theburnercanbedriventolowfirebeforeitisshutdown

FuelAirRatioControlTheBMU supports single point positioning (jackshaft)combustion control and parallel positioning combustioncontrol.OxygentrimcanbeaddedtoeithercontrolstrategybyaddingaPreferredZPprobe.Alinktrimactuator(LTA)canbeusedtovarytheairoutputinasinglepointpositioningsystem. Fuel valves and air dampers are controlled byhighprecision(0.1°accuracy)digitalelectricservos.EachdigitalservoincludesamicroprocessorandallservosarenetworkedtotheBMUchassis.BMUfuel-airratiocontrolfunctionsinclude:



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• Jackshaftorparallelpositioningcombustioncontrolissupported.

• Uptotenhigh-precisionservosarenetworkedtothecontroller,and4-20mAoutputsareavailabletocontrolVSDsforFDfan,FGRfan,IDfanorFWpump

• Upto11combustioncontrolpointscanbeprogrammedforeachoutput

• Separatepointsareavailableforstandby,purge,andlight-offpositions

• OptionalO2trimcontrolissupported• Separatepointsareprovidedforeachfuel’sVSDand

VSDbypassmodeforatotalofsixcurvesperservooranalog output

• Atomizing (steam or air) pressure (or differentialpressure)controlsetpointscanbeinputasafunctionoffiringrate

• Windbox oxygen control (monitored by a separateoxygen analyzer) allows the technician to enter awindboxoxygenvs.firingratecurve.TheBMUtrimstheFGRdamper(orFGRfanVSD)tomaintainFGRflow(asmeasuredbywindboxoxygencontent)oncurveatallfiringrates

• Duringboilerpurge,allservosarestrokedandtheirfeedbacksignalsarecheckedforservointegrity

BoilerControlFunctionsMany of themost common boiler control functions areincorporatedintheBMU.Thissimplifiesthecontrolsystemandofteneliminatestheneedforadditionalrelays,timers,orothercontrolhardwaremountedintheburnermanagementsystemenclosure.Additionally,theBMUacceptshard-wiredinputsforburneroff/onandremotefiringratethatmakeiteasilyintegratedwiththePreferredChiefDispatcherlead/lagsequencer.Othercontrolfunctionsinclude:

• Burnerfiringratecontrol(localPIDcontrol,remotefiringrateinput,orremotesetpointinput)

• Draft control with optional firing rate feed forward.Controlledoutputs includeastackdamper,oran IDfanVSD

• Feedwater control (single, two-, or three-element)ControlledoutputsincludeafeedwatercontrolvalveorfeedwaterpumpVSD

• Outdoorairtemperatureresetforhotwaterboilers.• Warmstandbyanddomestichotwateroverride• Lowfireholdbasedonboilershellorfluegas

temperature• Five auxiliary relays can be configured to control

commonboilerroomauxiliaries• Supervisedorautomaticwatercolumn

blowdownandlowwaterleveltestlogic• Boiler cold start functionallows for adjustable boiler

thermalshockprotection

BURNERMATE UNIVERSAL BOILER CONTROLLER SystemOverview

BMU-SM-15 Servo Motor with optional ‘QD’electrical Quick-Connects.

HighPrecisionDigitalElectricServoMotors

The servomotors provided as part of theBurnerMateUniversalareuniquetoPreferred.TheBMUcommunicatesdigitallywith amicroprocessor controller board in eachservo.Thecontrollerboardpreciselypositions theservomotorandperformscontinuoussafetydiagnostics.Ahighprecision, sealed feedback potentiometer continuouslyreportstheservopositiontothecontrollerboardandbacktotheBMUchassis.ThecontrollerboardincludespushbuttonsforZERO,CW,andCCW“jogging”oftheservomotor.Inaddition, LEDsprovide important diagnostic informationfor each servomotor. Servos are availablewith quick-disconnectfittingstoreducewiringtime.Torqueratingsfortheservomotorsstartat3ft-lbforsmallcontrolvalvesandgoupto720ft-lbforlargeairdampersorstackdampers.

BMUFuel-Air-FGRCrossLimitedPositionPacing“PositionPacing” isaunique featureof theBurnerMateUniversal thatassures thepositionsofallFuel,Air,andFGRServosandrelatedVSDspeedsremain“oncurve.”

FD Damper

FD VSD

Fuel Valve

Position Pacing

0.5 sec travel

0.5

sec

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l

Two Servo Example of Position Pacing



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BURNERMATE UNIVERSAL BOILER CONTROLLER SystemOverview

BMU Servo and Controller Board(with QD option)

Duringloadswings,positionpacinghelpsavoid:

• Periodsof lean combustion that can cause rumbling,vibration,orflame-outsduringfiringrateincreases

• Fuelrichconditionsthatcancausesmoking,burn-back,andexcessiveCOorunburnedhydrocarbonsduringfiringrate decreases

BMU “PositionPacing” assures that all servoactuatorsremain“oncurve”inthefollowingmanner:

• Allfuel,air,FGRServosandVSDsmovetogetherand“oncurve”--thereisnofuelorair“lead”or“lag”

• Each servo andVSDhas precise position or speedfeedbacktoensurethatalldevicesarecrosslimited.

• TheBMU“knows”howfareachservoactuatorandVSDcanmovein0.5secondsanduses“self-adaptive”positionpacingtoensurethatloadchangesnevercauseanyservoorVSDtolagbehindtheothers

• Εvery0.5seconds,theBMUexaminesallcurvesto“find”theservoorVSDworstcase0.5second‘shift’causedbyarequestedfiringratechange

• Basedonthecurves,allotherservosorVSDstargetpositionsare“scaledback”toassureALLdevicesarrive“oncurve”attheendofthenext0.5secondmove

BMU“positionpacing”isfullyautomatic,providesforsafercombustion control and drastically improved firing rateresponsetimesandrequiresnoadjustmentsbytheuser.

FlameScannersTheBurnerMateUniversalsystemincludesalineofPreferredInstrumentsflamescanners.Digital,microprocessor-basedscannersareavailableinultraviolet(UV)infrared(IR)andself-checkingUVmodels. Flamedetector and amplifierareintegratedintothescannerheadtoeliminatetheneedforseparate(panel-mounted)scanneramplifiers.Scannerhousingsaremachinedfromanodizedaluminum.Scannermountsare1/2”NPTF for theUVand IRversions,and1”NPTF for theself-checkingUVmodel.Eachscannerincludes a cooling air port for hot or dirty applications.Scanners include two LEDs--one blinks intermittentlydependingontheintensityoftheflamesignal,theotherLEDilluminateswhenthescannerclosesthe“FlameDetected”relayoutput.Electricalconnectionisbyathreadedmilitary-style quick disconnect.The scanners output a contactclosure forflameprovinganda4-20mAflamestrengthsignalfortroubleshootingdiagnostics.OneortwoscannerscanbeconnectedtoasingleBMUcontroller.Allscannersincludethesamepinoutandmilitary-stylequickdisconnectallowingforscannerstobeeasilychanged.TheBMUcanbeusedwith any othermanufacturer’s flame relay thatproducesa120VACcontactclosurewhenflameisproven.

BMU scanners available in ultraviolet, infrared, and self-checking ultraviolet. All connect by military-style quick disconnect fittings.

Up to four servos connect to each BMU-JBOX terminal. Each servo has a low voltage and high voltage quick connect cable. A single BMU-CABLE, and 120 VAC H, N, and G wires provide the

“home run” termination to the BMU chassis.



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BURNERMATE UNIVERSAL BOILER CONTROLLERSystemOverview

Digital CommunicationTheBurnerMateUniversal communicates via a secure,safetyrateddigitalprotocolwiththerequiredLCDkeypadandtheservonetwork.TheBMUchassiscommunicatesviaModbustotheoptionaltouchscreenOITandoptionalCommStationOIT-Bridge.BoththetouchscreenOITorOIT-BridgeactasprotocolconvertersandcanspeakModbus,ModbusoverEthernet,oranumberofotheropendigitalprotocolstoaBuildingAutomationSystem(BAS)orEnergyManagementSystem(EMS).BoththetouchscreenOITandtheOIT-Bridgearepre-loadedwithover75standardgraphicpages.Boiler overview screens canbe field-selected toresembletheboilerbeingfired.

Analog CommunicationTheBurnerMateUniversalacceptsindustrystandard4-20 mA, 0-5 VDC, 1-5 VDC, thermocouple, andthermistor inputs.Analog inputsareself-poweredby theBMU.Engineeringunits,orscaledvaluesareenteredbyparameterselectionduringtheBMUsetup.Analogoutputsare4-20mAandareavailableonlyforthedevicesshownabove.AllotheroutputsareontheBMUservonetwork.



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External Reset

Alternate Setpoint

FD Fan Speed Mode

LWCO By-Pass PushbuttonLow Water Alarm

High Water Alarm

Domestic Hot Water Override

Local Call for Heat

12

3

456

7

8Remote Call for Heat

Burner Off-On9

10

Recycle Inputs

Operating Limit

Aux. Low Water

Low Water Flow

Fresh Air Damper OpenSpare Limit

Oil Firing Requested

High Oil Pressure

Low Oil PressureLow Atomizing Pressure

Low Atomizing Flow

Lock-out Inputs

11

1213

1415

16

17

1819

20

High/Low Oil Temperature

Oil Gun in Position

Gas Firing Requested

High Gas PressureLow Gas Pressure

Fuel 3 Firing Requested

High Fuel 3 Pressure

Low Fuel 3 Pressure

Flame Scanner 1 Proven

Flame Scanner 2 Proven

21

2223

2425

26

27

2829

30

High High Limit Shutdown

Minimum Air Flow

FD Fan Energized

VFD FD Fan EnergizedLow Water Level Cutout

High Water Level Cutout

Low Draft Pressure

ID Fan EnergizedFGR Fan Energized

Spare Limit

31

3233

3435

36

37

3839

40

Leak Test High Pressure

Leak Test Low Pressure

Draft Damper Open

Purge Air Flow

Oil Valve Proof of Closure

Gas Valve Proof of ClosureFuel 3 Proof of Closure

41

4243

44

46

47

4849

Emergency Stop

51

52

53

5455

56

62

63

65

66

Ignition TransformerPilot Gas Valves

Atomizing Shutoff Valve

Oil Shutoff Valves

Oil Gun Post PurgeMain Gas Shutoff Valves

Aux. Relay 1 N.O. Contact



Aux. Relay 3 N.C. Contact

57

5859

60

Fuel 3 Shutoff ValvesMain Gas Vent Valve

FD Fan Motor Starter (C)

FD Fan Motor Starter (NO)

61

Lockout Contact

64

Aux. Relay 3 Common Contact

68

69 Aux. Relay 4 N.O. Contact

Aux. Relay 4 N.C. Contact67


71

72 Aux. Relay 5 N.O. Contact

Aux. Relay 5 N.C. Contact70


120 VAC Outputs

Dry Contacts

Status Inputs

Disable Windbox FGR Trim 45

Digital Inputs & OutputsAlldigital inputs to theBMUare120VAC from industrystandardswitchesandcontacts.Eachofthemostcommonboiler/burnerlimitswitchesispre-assignedtoaparticulardigitalinput.Sparelimitinputsareprovided.

Auxiliary RelaysFiverelayoutputsareavailable,eachconfigurableforthefollowingfunctions:commonalarm,auxiliaryfanstarter,fuel1,2,3auxiliaries,commonauxiliaries,limitsmade,outsideairlouvers,hotwaterpump/valve,LWCOauto-blowdownvalve,flameon,fuel1,2,3open.Relayoutputsarerated120VAC5ampsandareconfiguredbyparameterselection.



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Windbox Oxygen FGR ControlManymodern lowNOxandultra lowNOxburnershavechallenging limits of flammability.They require preciseamountsoffluegasrecirculation(FGR)forallfiringrates,despite changes in boiler load and ambient conditions.SincemeteringFGRflowratesisimpracticalwemeasurewindbox oxygen for closed loop control with a reliableprocess variablemeasurement.Automatic control ofwindboxoxygencontenthasprovenaneffectivemeansofconsistentFGRflow.

Atomizing Steam Pressure Control Traditionalatomizingsteampressurecontrol ishamperedby the limited turndowncapabilitiesof existingatomizingsteamdifferentialpressureregulatingvalves.Theoilflameisoftenover-atomizedat lowfire,under-atomizedathighfire,orboth.Thisproblemhasbeensolved,butbyusingveryexpensivecontrolvalveswithself-containedregulators/positioners.TheBurnerMateUniversalcontrollermonitorsatomizingsteampressure,andmodulatesaninexpensivequarterturnflowcontrolvalvetodelivervirtuallyanysteampressurerequiredatanyfiringrate.Alternately,anatomizingsteam/oildifferentialpressuretransmittercanbeusedandtheBurnerMateUniversalwillholdthesteam/oildifferentialpressure“oncurve”atallfiringrates.

Becausethissystemusesatightshut-offcharacterizedballvalveinsteadofaself-operatedpressureregulatingvalve,aseparateatomizingsteamshutoffvalve isnot required.Simply program the controller so that atomizing steampressureiszeroduringboilerstandby,andtheflowcontrolvalvewillbedrivenfullyclosed.Manyboilertechniciansliketoopentheatomizingsteamvalveduringpurgetoblowanywateroutofthelineandgetthelinehotpriortolightingofftheoilburner.TheBurnerMateUniversalprovidesseparate

FGR

S

Boiler AE

Windbox Oxygen

VFD Motor

S

BMU Controller

S

Fresh Air

Fixed PositionDamper

Gas FCV

Windbox oxygen FGR control schematic

BMUController

SOil

AtomizingSteamorAir

S Oil GunPT

OilServo

AtomizingPressureServo

AtomizingPressureXmtr

OilSSOV

OptionalShutoffValve

Atomizing steam pressure is monitored and held “on curve” at all boiler firing rates.

In this configuration, atomizing steam/oil differential pressure is monitored and held “on curve” at all boiler firing rates.

pointsforstandby,purge,andignitiontoaccommodatethispractice.

Fuel Flow Meter Display and Totalizing Tomonitor and track fuel usage (and savings) theBMUdisplaysandtotalizedfuelflowsforuptothreefuels.FuelflowsarealsoavailableonModbustocommunicatewithaplantEnergyManagementSystem(EMS)

BMUController

SOil

AtomizingSteamorAir

S Oil Gun

PT

OilServo

AtomizingPressureServo

AtomizingSteam/Oil

OilSSOV

OptionalShutoffValve

dPTXMR d/pxmtr



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Low Fire Fuel Transfer TheBurnerMateUniversalallowstheusertochangefuelswithoutshuttingdowntheboiler,inaccordancewithNFPA85Procedures for Single Burner Simultaneous Firing of Two Fuels for Fuel Transfer Only.Thefuelchangeoverisdoneatlowfire,butthelossofproductionismuchlessthanshuttingdowntheboiler,purging,andre-lighting.Thisprocedurecanbeveryconvenientforlightingoffdifficultoil-firedburners,orNo.6oilfiredburners.

TheBurnerMateUniversalhandlesthelowfirefueltransferaccordingtothefollowingsequence:

1. Theburner fires the “old” fuel in release tomodulatemode.

2. Thefuelrequestinputschange(eitherlocallybythekeypad,orremotelybyaBAS)indicatingwhatthedesired“new’”fuelwillbe.

3. Thecurvedataforthenewfuelischeckedforerrors.4. TheBMUwaitsforthenewfuel’slimitstomake.5. Bothfuelactuatorsaresenttotheirignitionpositions.6. The controller ‘paces’ to the ignitionpositionwith all

combustionactuators/VSDs‘oncurve’.7. TheBMUwaits until both fuels reach their ignition

positions.8. Theair damper/VSDsare thenbiasedup toprovide

additonalairforthenewfuel.9. Oxygen,FGR,andfullmeteringtrimarenulledthrough

thebiasedairphases.10. TheBMUwaitsuntilthedamper/VSDsareattheirbiased

position(s)11. TheBMUthenopensthenewfuelSSOVs.Theoldfuel

flameignitesthenewfuel.12. TheBMUwaitsforMTFIsecondstoallowtheflameto

stabilize.13. TheBMUclosestheoldfuelSSOVs.14. Theairbiasisthenremoved.15. TheBMUwaitsfor10secondstoallowtheairdamper/

VSDstogetback“oncurve”.16. TheBMUthenreturnstothereleasetomodulatestate

withonlythenewfuelfiring.

Afuelselectorswitchwithacenter“Dual”positionallowsanoperatortomanuallyextendthedualfuelfiringperioduptoamaximumof90seconds(fieldadjustable).

Lowfirefueltransferisenabledbyparameterselection,andisprotectedbyan“engineer”levelpassword.

Tandem Oil/Gas Valve Servo Option For retrofitapplications, theBurnerMateUniversalallowsreplacementofthejackshaftactuatoronagasandoilfiredburnerwithasingleBMUservoandmaintainsthelinkagetotheoilandgasvalves.Theairdamperistakenoffthelinkageanddrivenbyasecondservoforparallelpositioningcontrolofbothfuels.AZPprobecanbeaddedtothesystemforparallelpositioningwithoxygentrimcontrol.Thisfeaturesreducesthenumberofservosrequiredforagas/oilburnerretrofit,andspeedsinstallation.

Separatecurvesareprovidedforstandby,purge,andignitionpositionsforoilandgas.TheBMUpositionsthegas/oilvalve(jackshaft)actuatorbasedontheBMSfuelselectionandthecorrespondingfuel’scurvedata.



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BURNERMATE UNIVERSAL BOILER CONTROLLEROrderingInformation

BMU Chassis SelectionThereareseveralBMUchassistochoosefromdependingonthefunctionalityrequiredinthecontrolsystemandthemountingofthe(required)LCDkeypad.The“basic”chassissupportsalltheflamesafeguard,combustioncontrol,andotherboilercontrolfunctionsoftheBMU.

The“expanded”chassissupportsalloftheabovefunctionsplusdraft,feedwatercontrol,atomizingsteam/airpressurecontrol,FGRwindboxoxygencontrol,aswellasflowmetersignal display and totalizing. Physically, the expandedchassiscontainsanextraanalogI/Oboardmountedwithinthechassishousing.

Toenableoxygenmonitoringoroxygentrim,the“Z”designationinthefifthdigitofthepartnumbermustbespecified.The“Z”optionandBMUchassisdonotneedtobepurchasedatthesametime,thisfeaturecanbefield-activatedatalaterdate.TheZPprobeandconnectingcablearepurchasedseparately.

ThesixthdigitinthepartnumberspecifiesthemountingoftherequiredLCDkeypad.Inmostinstances,thekeypadwillbeshippedloosetobeflush-mountedonthedoorofanenclosure.Alternatively,itcanbemountedinthechassiscovereitherhorizontallyorverticallyforlandscapeorportraitchassisorientation,respectively.Thekeypadisrequiredwhetherornottheoptional10”OITcolortouchscreenisprovided.

BMU Chassis SpecificationsElectrical

InputVoltage: 120VAC(+/-15%)Frequency: 60Hz,singlephaseConsumption: 42VA

EnvironmentalOperatingTemperature: 32to140deg.FStorageTemperature: -20to150deg.FHumidity: 15to95%

noncondensingOrderingInformation

Chassis Description Catalog Number

“Basic”controllerchassissupportsuptoseven(7)independentservoactuators--3forfuel,1forair,1forFGRand2Auxiliaries.Alsotwo(2)4to20madcoutputsforFDfanVSD/orAuxiliary2curve(ifnotaservo)

“Expanded”controllerchassisisrequiredfordraftorfeedwatercontrol.Supportsuptoten(10)independentservoactuators--3fuel,1air,1FGR,1feedwaterflowcontrolvalve,1draftdamperandatomizingsteamflowcontrolvalve.Alsouptosix(6)4to20madcoutputsfor:firingrate,FD,IDfanVSDs,Auxiliary2valveordamper,adraftdamperandafeedwatercontrolvalveorfeedwaterpumpVSD.

ControllerdoesnotsupportZPoxygenprobe

ControllersupportsZPoxygenprobe(fieldupgradable)

LCDkeypadisshippedloose(standard)

LCDkeypadisflush-mountedontheBMUcontrollerchassiscoverforlandscapechassismounting

LCDkeypadisflush-mountedontheBMUcontrollerchassiscoverforportraitchassismounting

BMU-______0

0

1

N

H

V

0

Z



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Description Catalog NumberControlPanel,24”Hx30”Wx10”D BMU-PANEL243010ControlPanel,30”Hx24”Wx10”D BMU-PANEL302410OITControlPanel,24”Hx30”Wx10”D BMU-PANEL243010-OITOITControlPanel,30”Hx24”Wx10”D BMU-PANEL302410-OITCustomDesignedEnclosure Consult Factory

BMU Standard Enclosure OptionsFourstandardenclosureoptionsareofferedfortheBMU.ThestandardenclosuresareNEMA12,hingedontheleft,includetwolockingmechanisms,andfeaturethefollowingcomponents,mountedandwired:

• LCDkeypad,burneroff-onselectorswitch,fuelselectorswitch,pilotlights,andanemergencystoppushbuttonmountedontheenclosuredoor.

• Abeaconandalarmhornaremountedandwiredtotheenclosureshell.

• BMUchassis,circuitbreaker,fuses,and24VDCpowersupply(ifOIToptionsarespecified)andanumberof120VACterminals.

• The panel-mounted devices are factory-wired asshown.All other devices are field-wired directly totheBMU terminals.Standard drawings showing thepanelarrangementand the internalwiringschematicarepresentedintheBurnerMateUniversalInstructionManual.

AdditionalDINrailisprovidedtomountotherdevicesasrequired,inthefield.Customdesignedcabinetareavailable.Consultfactoryforoptions,leadtimes,andpricing.

BMU-PANEL-2430-OIT

Interior view of BMU-PANEL-2430-OIT standard enclosure




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BMU Digital Servo ActuatorsBMUservosare available in output torques from3 ft-lbto720ft-lbs.Eachincludesanactuatorpositionerboard,and integral feedback potentiometer. The feedbackpotentiometer is used to prove servo position therebyeliminatingtheneedforauxiliaryproofofpositionswitches.Servoscanbeusedforthefollowingcontrolfunctions:• Natural gas, fuel oil and/ or “other gas” flow control

valve(s)• FDfandamper• Auxiliaryfinalcontrolelement(secondFDfandamper,

atomizingsteam/airvalveor…)• FGR damper• PreferredInstrumentsLTAoxygentrimactuator• Jackshaftactuator• Boileroutlet(stack)damper• Feedwatercontrolvalve• Auxiliaryservoforairsleeve,secondgasFCV,etc.

Forthelarger“UM”Actuatorsafloorstandisincludedasastandard.Damper/actuatorinterconnectinglinkagerod,linkagerodendsanddrivearmsmustalsobepurchased.


BMU Chassis SpecificationsElectrical

Motor: 120VAC(+/-15%),60Hz,singlephase

BMU-SM <0.2ABMU-UM <2ABMU-UM-720 3.4APositioner 24VDC,23mA

Servo PerformanceSpeed: 25sec/90°Rotation: 15°to180°(SM)

0°to90°(UM)DutyCycle: 100%Accuracy: +/-0.1°(SM)

+/-0.4°(UM)

EnvironmentalNEMARating:BMU-SM NEMA12BMU-UM NEMA4OperatingTemperature 32°to140°F

MechanicalBMU-SM-3 4”Wx5.8”Hx5.5”D

8mm“D”shaftBMU-SM-15 5”Wx5.8”Hx5.5”D

12mm“D”shaftBMU-SM-37 5”Wx6.7”Hx5.5”D

12mm“D”shaft

ConsultfactoryforBMU-UMdimensions

“SM” Model DescriptionCatalog Number

ServoActuator,3ft-lb.Torque(ShaftExtensionrequired)

BMU-SM-03

Asabovew/15ft-lb.Torque(ShaftExtensionrequired)

BMU-SM-15

Asabovew/37ft-lb.Torque(ShaftExtensionrequired)

BMU-SM-37

ElectricalQuickDisconnectOption BMU-SM-xx-QD

“UM”ModelDescriptionCatalogNumber

RotaryActuator, 72 ft-lb. torque. In-cludesfloorstand,positionerboardandinterconnectingcable.

BMU-UM-072-FS

Asabovew/140ft-lb.torque BMU-UM-140-FSAsabovew/280ft-lb.torque BMU-UM-280-FSAsabovew/420ft-lb.torque BMU-UM-430-FSAsabovew/720ft-lb.torque BMU-UM-720-FSElectricalQuickDisconnectOption BMU-SM-xx-QD

ModelDescriptionCatalogNumber**

BMUCommQuickDisconnectCable COMM-CABLE-ASSEMBLY-xx**

BMUPowerQuickDisconnectCable PWR-CABLE-ASSEMBLY-xx**

BMUQuickConnectTerminationBox BMU-JBOX

BMU“HomeRun”Cable BMU-CABLE-xx**

Servomountingneedstobeassolidaspossibletominimizehysteresisandensureconsistentburnersettings.

**Specifycablelengthinfeet(3,6,or12ft)



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StandardValveMountingBracket/CouplingPartNumbersValveManufacturer&

ModelValveSize ServoModel BracketModel CouplingModel

HoneywellV51EGasButter f ly Valves/5PSIGrating

1-1/2” BMU-SM-15 Factory Factory2” BMU-SM-15 “ “

2-1/2” BMU-SM-15 26189 B-201543” BMU-SM-15 C-30009 B-201544” BMU-SM-15 C-30009 B-20154

Hauck BVA Gas &AirButterflyValves/5PSIGrating

1-1/2” BMU-SM-15 Factory Factory2” BMU-SM-15 “ “

2-1/2” BMU-SM-15 “ “3” BMU-SM-15 “ “

EclipseBV-AFullPortGas ButterflyValves(360 deg. rotation)/5PSIGrating

3/4” BMU-SM-15 Factory Factory1” BMU-SM-15 “ “

1-1/4” BMU-SM-15 Factory Factory1-1/2” BMU-SM-15 “ “2” BMU-SM-15 “ “

2-1/2” BMU-SM-15 “ “3” BMU-SM-15 “ “

M i l w a u k e e B BSeriesGas ButterflyVa lves /150 PSIGrating

3/4” BMU-SM-37 26178 (1) 26173-1B(1) 26179

(2) 5636-008A-101” BMU-SM-37 26178 (1) 26173-1B

(1) 26179(2) 5636-008A-10

1-1/4” BMU-SM-37 26178 (1) 26173-1B(1) 26179

(2) 5636-008A-101-1/2” BMU-SM-37 26178 (1) 26173-1B

(1) 26179(2) 5636-008A-10

2” BMU-SM-37 26178 (1) 26173-1B(1) 26179

(2) 5636-008A-10



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StandardValveMountingBracket/CouplingPartNumbers(continued)

Milwaukee “HP1L”&“HP1W” Series GasButterfly Valves/150PSIGrating

2-1/2” BMU-SM-37 Factory Factory

3” BMU-SM-37 20150 20149-1

4” BMU-SM-37 20150 20149-1

HauckMOV&MCOVOilValves/300PSIGrating

3/8” BMU-SM-15 Factory Factory

1/2” BMU-SM-15 26177 26180-1

Wo r c e s t e r C P TCharacterized SeatBallValves/300PSIGrating (gas,water, orsteam)



1” BMU-SM-37 26187 26186

1-1/2” BMU-SM-37 20136 20140

FlowTekSeries 8000Characterized SeatBallValves.300PSIGrating (gas,water, orsteam)

1/2” BMU-SM-15 20135 (2) 26173(1) 20152

(2) 5636-008-103/4” BMU-SM-15 20135 20152

1” BMU-SM-15 20136 20138

1-1/4” BMU-SM-37 20136 20138

1-1/2” BMU-SM-37 20143 (2) 26173(1) 20152

(2) 5636-008-102” BMU-SM-72 20143 20146

F l o w Te k S e r i e s“ F 1 5 ” & “ RF 1 5 ”Characterized SeatBallValves.150PSIGrating (gas,water, orsteam)

2” BMU-SM-72 20143 20146

2-1/2” BMU-SM-72 20144 B-20009

3” BMU-SM-140 20144 20163

4” BMU-SM-140 20167 B-20016

BMU-UM-72-FS Servo with Integral Floor Stand



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ZP Zirconium Oxide In-situ Oxygen Probe

ModelDescriptionCatalog Number

In-SituDetector&ProbeAssembly20” ZP-20





ZP Probe Connecting Cable – SevenWire.Specifylengthrequired(Maximumis500feet)

190130

ZPProbeMountingKit,Includes:(1) 3”125#Castironthreadedflange(1) 3”Pipe,half-coupling,threaded(1) 3”x8”longpipenipple,threaded(8) Hexnut,5/8-11(8) Washer,5/8(2) 1/8”Ballvalve(brass)(1) 3”Gasket(50) Footcoppertubing,¼”OD(8) Hexheadscrew,5/8-11x2½(2) Straightfitting(brass)

190680

ZP Oxygen Analyzer ProbeTheBMUusesthesameZPprobeastheBurnerMateTS,PCC-III,andUtilitySaver.TheZPcontroller/amplifierisbuiltintotheBMUchassis.

ZPprobesshouldbefieldcalibratedwithtestgasesevery6-12months. However, a new probe includes factorycalibrationparametersthatcanbeenteredintotheBMULCDkeypad.Thiseliminatestheneedtohavecalibrationgasduringtheinitialstart-up.

TheBMUallowsforstackoxygenindication,andoxygentrimdependingontheparameterselectionsmadeduringcommissioning.Whenastacktemperaturethermocoupleisinstalled,theBMUcalculatescombustionefficiencyforNo.2oil,No.6oil,ornaturalgas.



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BurnerMate Universal OIT Touch ScreenAll of the control functionsof theBurnerMateUniversalcan be accessed through the LCD key pad.TheBMU-OIT-10colortouchscreendisplayisavailableforenhancedgraphicsandcommunications.Supportedcommunicationprotocolsinclude:

• 10/100 Base Ethernet, Modbus TCP/IP, ModbusRTU,SCADA/BASconnection,BacNet IP, andBMUconnection

• OneRS-485port

Over 75 pre-programmedgraphics pages are included.Boiler overview screens are field-selectable to fit theapplication. Typical Boiler Overview Screen

Touch Screen Specifications

Electrical InputVoltage: 24VDC,1.4A

Monitor PerformanceSize: 10.4”Colors: 256VGAResolution: 640x480pixels

EnvironmentalNEMARating: NEMA4X(flush-mount)

Fuel Combustion Curve Setup Screen

Trending screens help fine-tune control loopsController I/O screens help troubleshoot problems

Description Catalog Number

10.4”OperatorInterfaceTerminalColorTouchScreenDisplaywithBMUoperationandcommissioningdisplays. BMU-OIT10

OITTerminalWiringAdapter 190777

120VAC/24VDC/2.5ADINrailpowersupply 92443



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BMU Flame ScannersTheBMUcanacceptoneortwoflamescanners.Theyareavailableinultraviolet,infrared,andultravioletself-checkingversions.

Unitized DesignTheBMUscanners,likemostmodernflamescanners,areunified.Thismeanstheflamedetectorandamplifiercircuitryarecombinedandhousedinthescanner.Thiseliminatestheneedforaseparateenclosure-mountedamplifier.Whethertheflamedetectorcontainsanultraviolet,infrared,orself-checkingultravioletdetector,theoutputstotheBMUarethesame--acontactclosurethatprovesflameisdetected,anda4-20mAsignalproportionaltotheflamesignal.IntheBMU,the4-20mAsignalisusedforflameindicationonly.

Advanced DiagnosticsOn-boarddiagnostics in theflamescanners, andbuilt into theBMU,make trouble-shootingof a flamescanningproblemeasy.AllBMUscannerscontaintwoLEDsonthefrontofthescanner.The“flamestatus”(left)LEDblinksatarateproportionaltotheflamesignalstrength.The“flamerelay”LEDilluminatescontinuouslywhentheflamesignalissufficienttoclosetheflameprovenrelay.

Inaddition to the twoLEDs, thescannersoutputa4-20mAsignaltotheBMU,proportionaltotheflamesignal.TheflamesignalstrengthcanbeviewedfromseveralscreensontheBMU.

BMU Scanners Feature:• Digitalflamesignalprocessingformorereliableflame

detection.• Highqualityfusedsilicaquartzlens.• MachinedalloyhousingwithNEMA4seals.• Militaryspecificationcomponentsusedinessentialintegratedcircuitsandconnectors.• Military-stylequickdisconnectfittingsallowfor

scannerreplacementwithoutrewiring.• Redundantflamerelaycontactsarefullysupervised.

UV Self-Check Scanners Feature:• Detectorandsignalprocessorsautomaticallycheckedevery10seconds.• Newopticalinterruptertechnologywith100millioncyclelifespan.(That’sover30years!)

• Rugged1”NPTFscannermounting.

Ultra-Violet Flame ScannersTheBMU-UVandBMU-UVSCflamescannersuseaUVdetectortubeasasensingelement.IncomingUVradiationfroma flame is focusedandamplifiedoptically.TheUVradiationenergizes thedetector tube,whichworkson theGeiger-Mueller principle.TheBMU-UVSCself-checkingdetectorandpulseprocessorarecontinuouslysupervised

BMU-UVSC and IR Flame Scanners

bymeansoftheuniqueopticalinterruptermechanismthatbreakstheUVlightpathbetweenlensanddetectortube.Thescanner’spulseprocessorisfail-safebynature,sinceanyfailuremoderesultsinatotallossofsignal.

Infrared Frequency-Based ScannersTheBMU-IRflamescannerusesa lead sulfide sensingelement.Thepresenceofaflame isdetectedbysensingthe variations of flame luminosity.This technique aidsdiscriminationof flame radiatedenergyandbackgroundradiation fromheated furnaceparts.Consult factory foravailabilityofIRscanners.

Recommended Scanner

Application UVSC IRGasOnlyFired XNo.2Oil,AirAtomized XNo.2Oil,SteamAtomized XNo.2Oil,PressureAtomized XNo.6Oil,SteamAtomized XNo.6Oil,RotaryCup XDigesterorLandfillGas XRefineryGas X



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ScannerApplicationConsult the burnermanufacturer to determine themosteffectiveflamescanner type for yourburnerapplication.However, typicallyultraviolet(UV)scannersareusedforgasflamesandinfrared(IR)scannersareusedforheavyoil,orsteam-atomizedlightoilflames.Preferred’sUVflamescannersaretraditionalUVtubescanners.TheIRscannerusesaleadsulfidedetector.

BecauseUVtubescannerscanfailshowingflame(runawayscannercondition)aself-checkingUVscannershouldbeusedforapplicationswheretheburnerdoesnottypicallycycleoffatleastonceineacheighthourperiod.IRscannersdonottypicallyfailshowingflame.

BMU-UVSC-10CUltraviolet

Self-CheckScanner

BMU-UV-10CUltraviolet

NonSelf-CheckScanner

BMU-IR-10CInfrared

NonSelf-CheckScannerMechanical:OverallLengthDiameterHousingConstructionFinishSightTubeConnectionPurgeAirConnection

7”(177.8mm)3.25”(82.5mm)Machined5052Alum.ClearAnodized1”NPT(female)3/8”NPT(female)

3”(76.2mm)2.25”(57.15mm)Machined5052Alum.ClearAnodized1/2”NPT(female)3/8”NPT(female)

3”(76.2mm)2.25”(57.15mm)Machined5052Alum.ClearAnodized1/2”NPT(female)3/8”NPT(female)

Electrical:SupplyVoltageRequiredPowerContact OutputCurrent OutputCurrent Output specs(2wirecurrentloop)

120VOLT50/60HZ2VA120VAC,1amp4to20madcSpanerror–0.5%Non-linearity–0.03%Loop supply voltage 7.5to36Volts

120VOLT50/60HZ2VA120VAC,1amp4to20madc

120VOLT50/60HZ2VA120VAC,1amp4to20madc

Environmental:ClassTemperature

NEMA40to140deg.F.

NEMA40to140deg.F.

NEMA40to185deg.F.

Optical:Lens

FusedSilica FusedSilica FusedSilica

SpectralSensitivityWavelength(nanometers)

180–230(UV) 180–230(UV) 400–1050(IR)

BMU-IRinfraredscannerswillbeavailablesoon.Consultfactoryforavailability.

DescriptionCatalogNumber

Ultraviolet Self-CheckScanner; 10 ftcable & connector BMU-UVSC-10C

UltravioletNonSelf-CheckScanner;10ft cable & connector BMU-UV-10C

InfraredNonSelf-CheckScanner;10ftcable&connector.Consult factory foravailability.

BMU-IR-10C

ScannerCable(lengthsotherthan10’) 5000-02-xx



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BMU_EditIn the tradition of PCC-III_Edit and PWC_Edit, theBurnerMateUniversalisavailablewithBMU_Editsoftwarethat runs on yourWindows-basedPC and allows youto set the parameters of the BMU from your laptop.CommunicationbetweentheBMUandyourPCisdoneviaastandardUSBA/B(printer)cable.

Easy pull-downmenusand text boxes allowparameterselectionsinyourofficetobewrittenintotheBMUchassiseither before installationor during commissioning.Oncecommissioningiscomplete,BMU_Editallowsyoutoreadfrom the BMU chassis and save the latest parametersettingsandcurvedatainthePC.ThissettinginformationcanbeusedtosetupadditionalBMUsorusedasanarchiveiftheBMUconfigurationbecomescorrupted.

BMU_Edit includestoolsthatallowtheperformanceofaparameterchecktomakesureparametershaven’tbeensettoincompatiblevalues.ThesoftwarewillalsoconvertsettingdatafromoneBMUversiontoanother.Inaddition,BMU_Edit can compare two BMU configurations andmakea detailed list of the differencesbetween the twoconfigurations.Thisfeatureisimportantwhenmorethanonetechnicianmayworkonthesameboiler.

The compare function tracks any changes made to a BMU configuration for easy trouble-shooting.

The curve viewer function allows a technician to quickly view all the combustion related curves input in a BMU. This can be useful when diagnosing a problem. It can also be used to archive curve information quickly and easily. Parameter settings and fuel-air curves can be written back to the BMU, but the points must be verified before leaving commissioning mode.

ModelDescription

Catalog Number

BMU_EditSoftware BMU_Edit



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Digital Communication OptionsManyplantownersandengineersdesiretomonitorthestatusoftheboilerroomremotely.TheBMUhasModbusaddressesassignedforthestatusofmanydigitalandanaloginputsandoutputs.ThisdataisaccessiblebyModbususingtheRS485connectionontheBMUchassis.TheRS485connectioncan

beconvertedtoEthernetusingeithertheOITtouchscreenoranOIT-Bridge.Generally,anydatapointdisplayedonthetouchscreenhasaModbusaddressandcanbemonitoredremotelyviaModbus.APWC,PCC-III,orDCS-IIIloopcontrollercanbeusedtomakeanyotherpointsavailableviaModbus.

This is the most common digital communication scenario used with the BMU. The OIT touch screen is supplied for its graphics capability, and is also used to convert the RS485 bus to Ethernet. There are many terms for the control system the BMU typically interfaces with, including: Distributed Control System (DCS), Building Automation System, (BAS) Energy Management System (EMS) or Preferred Supervisory Control and Data Acquisition System (SCADA). Most of these systems can communicate via Modbus over Ethernet or have converters that can communicate via Modbus.

As an economical alternative to the OIT touch screen, Preferred offers the OIT-Bridge that provides a pre-configured communication interface between the Modbus RS485 BMU chassis and Modbus over Ethernet. The OIT-Bridge is pre-configured to the Modbus addresses of the BMU. It offers the same communication capabilities as the OIT touch screen at a much lower price.

A l l o f the BMU chass is opt ions communicate using Modbus protocol on an RS485 bus without any additional equipment required.

RS485 ETHERNETor BacNet IP

BMUCHASSIS

OITTOUCH SCREEN

PLANTDCS, BAS,

EMS, SCADA, ETC.

RS485 ETHERNETor BacNet IP

BMUCHASSIS

OITBRIDGE

PLANTDCS, BAS,

EMS, SCADA, ETC.

RS485Modbus

BMUCHASSIS

PLANTDCS, BAS,

EMS, SCADA, ETC.



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This is the ultimate in-plant monitoring capability in an entirely pre-engineered package. Up to three boilers can be controlled and monitored using off-the-shelf BMU boiler masters, a Chief Dispatcher plant master, and the CommStation communication interface that provides a single Ethernet connection to the plant. Because the components of this system are completely pre-engineered, this is a very economic package that will typically be competing with a custom engineered PLC-based system.

Description

CatalogNumber

Optionalwebbrowserremotecommunicationmodulewithpre-configuredBMUoperationandcommissiondisplaysvisiblefromastandardwebbrowser.OneEthernet,oneRS-485,andtwoRS-232communicationportsarebuilt-in.

BMU-OIT-BRIDGE

Historicalmemory2GBcompactflashcardforextendedhistoricalmemorycollectionandexporttoMSExcel 90283

Communicationexpansioncard.ProvidesoneadditionalRS-232andRS-485port. 90284CommStationthreeboilerBMU/ChiefDispatcherEthernetinterface 190781–RS-485120VAC/24VDC/2.5ADINrail-mountedpowersupply 92243

MULTIPLE BMUs IN ONE PLANT SINGLE ETHERNET CONNECTION TO

PLANT

RS485

RS485

RS485 ONE CHIEF DISPATCHER

PREFERREDCOMMSTATION190781-RS-485

ETHERNET

RS485



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BURNERMATE UNIVERSAL BOILER CONTROLLERSuggestedSpecifications

1. Quality AssuranceTheboilercontrolsystemshallbemanufacturedandsupportedintheUnitedStatesbyPreferredInstruments.Theburnerfuel-air-FGR ratio control systemand the burner flame safeguardsystemshallbemanufacturedand labelled inaccordancewithU.L.372,U.L.1998,andCSAC22.2#199.SimplysupplyingULrecognizedindividualcomponentsisnotsufficient.Theassembledcontrolcabinetasawholemustbeinspectedforproperwiringmethods, fusing, etc., andmust be labeled as conforming toUL508AandCSAC22.1#14.InspectionandlabelingshallbesupervisedanOSHAapprovedNationallyRecognizedTestLab(NRTL).ThesystemshallcomplywithNFPA85“RequirementforIndependence,” the flamesafeguard systemshall beprovidedwith independent hardware shall bephysically separated fromthecombustioncontrollogic.2. Parallel Positioning Combustion ControlAparallelpositioningcombustioncontrolsystemwithoxygentrimand(optional)VSDcontrolshallbeprovidedforeachboiler.Eachsystemshallbedesignedtoprovidecontinuousboileroperationwithinboilerdesignlimitswithahighlevelofsafetyandenergyefficiency. As required the system shall provide continuousmonitoringandcontrolofsteampressure(orwatertemperature),waterlevel,combustionairandfuelratio&fluegasrecirculation.Thesystemshallbefullyintegratedtotheburnermanagementsystemtoprovidefullyautomatic,safeandreliablestartupandshutdown.Positionpacingshallbeused toensureup toeightservoswillbecontinuallymonitoredandheld“oncurve”duringboilerloadchanges.3. Oxygen Trim SystemProvideaboilerbreechingmountedin-situ,zirconiumoxideoxygenanalyzer for eachboiler.Extractive typeoxygenanalyzersarenotacceptableforcombustioncontrol.Theprobeshallbeofasuitablelengthtosensetheoxygenlevelinthemiddlethirdofthebreeching.Allwettedpartsshallbestainlesssteel.Theoxygenanalyzershall:• Includecontinuousself-diagnosticswithdiagnosticcodesfor

atleast10commonfaults.• Automaticallysendthe trimcontrol to the ‘null’positionand

triggerthealarmdrycontactsintheeventofanoxygenanalyzerfault.

• Thedetectorshallbefieldreplaceablewithoutremovingtheprobefromthestackandshallnotrequirespecialtools.

• Theanalyzershallautomaticallyperformperiodicdetectorcellimpedanceteststobeusedbytheoperatorasanindicationofcalibrationshift.

• Analyzercalibrationshallbepushbuttonsemi-automatic(notrim pots) with English language prompts and diagnosticmessages.Analyzeroutputshallbefieldselectableas0-10%or0-21%withoutfieldre-calibration.

4. Flame Safeguard System (FSG)Integral to the control system furnished shall be a BurnerManagementSystem (BMS) /FlameSafeguardSystem (FSG)controller.Thesystemshallbedesignedtoensurethesafestart-up, on-line operation, and shutdown of fuel firing equipment.Burnermanagement system components shall be located inthe combustion control cabinet and shall be fully integratedforautomaticsequencingof lightoffandshutdown.ForsafetytheBMSmicroprocessorandBMSVDshallbeonaphysicallyseparatecircuitboard.Microprocessor-basedFSGshallprovide:safetyinterlocks,flamemonitoringprotection, and timed sequences.Sequences shallincludeforceddraftfanstartandstop,furnacepurge,burnerlightoffandshutdownandpost-purge.TheFSGshallbecapableoffiringuptothreefuels(twogasfuels,oneoilfuel),onefuelatatime.Fuelchangeovershallfromoiltogas,orgastooilfiringshallbeaccomplished“onthefly”atlowfirewithoutboilershutdownperNFPA.A panel front-mounted English language, four line, twentycharacter LCDmessage display shall be provided to displayflamesignal strength, startup and shutdown sequence status,alarm,systemdiagnostic,first-outmessagesandburnerhistoricalinformation.Historicalinformationshallincludethestatusofalllimitsandservosforthelasttenlockouts.To ensure boiler lowwater cutouts areworking correctly, thecontrollershallbecapableofperformingadailyautomaticwatercolumnblow-downtest.Theusershallselectthetimeofdayanddurationofthewatercolumnblow-downtest.Thecontrollershallensure the lowwater cutoff switches are functioning correctly,andalarmtheoperatororlockouttheboilerifitdetectsaswitchmalfunction.To prevent nuisance trips, the flame safeguard system shallaccommodate two flame scannerswith one required to proveflame.Thecontrollershallprovide120VACor24VDCscannerpower,andaccept twoanalog inputs indicatingflamestrength.Flamesafeguardsystemshallincludeoilgunpostpurgeforoilfiring.Assuredlowfirecutoffshallbeprovided.Foradditionalnuisancetripprotection,fieldadjustabletimedelaysshallbeprovidedforF.D.fanstart,freshairdamper,minimumairflow,lowdraftcutout,andfuelpressurelimits.Fivefieldselectableauxiliaryrelaysshallbeincludedforcommonalarm,auxiliaryfanstart,blow-down,flameon,fuelvalveopen,hotwaterpumporvalve.Toprotectagainstdryfiring,anoptionshallbeavailableforhighfluegastemperaturelockout.Toensureairswitchesarefunctioning,aminimumairflowpressureswitchandpurgeairflowpressureswitchsafestartcheckshallbeincluded.5. Feedwater ControlProvideaboilerwaterlevelcontrollercapableofsingle-,two-,orthree-elementfeedwatercontrolwiththeabilitytoautomaticallyswitchbetweencontrolstrategiesdependentonsystemdemands.6. Draft ControlThecontrollershallprovidetwo-elementdraftcontrolutilizingaPreferredInstrumentsJC-22XMTRdrafttransmitter.Burnerfiringrateshallbeusedasafeedforwardforimprovedresponsetoloadchanges.Thecontrolshallprovidebothautomaticandmanualdampercontrol.Alladjustmentsshallbemadefromthefrontpaneldisplayinengineeringunits.



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BURNERMATE UNIVERSAL BOILER CONTROLLERSuggestedSpecifications

7. Flue Gas Recirculation Valve ControlThecontrollershallhaveacharacterizablesetpointcurveoutputsignal for the fan to vary or damper its speed.All the logicrequired to automatically signal pre-purge, postpurge, light-off,andburnermodulatecyclesshallbeprovidedwithinthecontroller.Alternatively,thecontrolwillregulateFGRaccordingtoapresetwindboxoxygensetpointcurve.8. Windbox Oxygen FGR ControlThecontrollershallacceptananalog input forburnerwindboxoxygentobeusedasameasureoffluegasrecirculationrate.During commissioning, awindboxoxygen vs. firing rate curveshallbeestablished.Thecontrollershallmodulatethefluegasrecirculationvalve (or fluegasblowermotorVSD) tomaintainwindboxoxygenonthepre-establishedcurvedespitechangesinambientconditions.9. Atomizing Media Pressure ControlThecontrollershallacceptaninputforatomizingsteampressureoratomizingsteam/oildifferentialpressure.Duringcommissioning,anatomizingsteampressure(oratomizingsteam/oildifferentialpressure)curveshallbeestablished.Thecontrollerwillmodulateanatomizingsteamflowcontrolvalvetokeeptheatomizingsteampressureoncurveatallfiringrates.10. Additional Control Requirements:• Minimumnumberoff(x)Curvestobeprovidedperservo:6• Minimumnumberofpointsperf(x)Curvetobeprovided:11• ColdFGR lowfirecutbackshallbeprovidedwhenFGR is

utilizedforNOxreduction.• SeparatecurvesshallbeprovidedforFDfanfullspeedbypass

ofVSDincaseofVSDfailure.• Controllershall include thecapabilityof receivingaremote

firingrateinputandremotesetpointinput.• Controller shall include dual outdoor reset setpoint curves

(normalandsetback)• Controllershallincludewarmstandbystart/stopcycle.• Controllershallincludelowfirehold,andcoldstartwarmup

ramping.• Allexternalorauxiliarypowersuppliesnecessaryforelectronic

transmitters(orfinalcontrolelement)shallbeincluded.• BoilercontrolsoftwareshallbeU.L.372/U.L.1998recognized

and inaccessible toprevent tampering.Unitcommissioningshallbebyparameterselection,notrequiringladderlogicorblockwareprogramming.

• Thecontrollershallacceptstandard4-20mA,1-5VDC,orthermistorinputsforanaloginputs.Nospecialsensorsshallberequired.

• Controllershallreceiveanddisplayinputsforfuelflow,airflow,andsteamflow.Controllershallbecapableoffutureupgradestofullymeteredcombustioncontrol.

11. OIT Color Touch ScreenProvideasanoptionaten(10)inchOperatorInterfaceTerminal(OIT) designed to provide local operation, graphic display ofinformation, alarmmessage display, historical and real timetrending,remotecontroltuning,x/yplotsoffuel-aircurvedatafor intuitivecommissioning,Ethernetconnectivityandstandardinternetbrowserremotecommunication.TheOITshallcontainaminimum of 75 graphic pages and be networked to theboilercontrolandburnermanagementsystems.TheOITshallprovidegraphicpagesallowing step-by-step commissioningofthecontrollerparametersusingEnglish languagepromptsandselections.The systemshall bean industrial hardenedoperator interfaceterminal.The terminal shall be enabledby thewebandallowremotemonitoringviaastandardinternetbrowserandsupportModbusTCP/IPMaster,TCP/IPSlave,RS-485ModbusMaster,andEthernetcommunications.12. High Torque Servo Features:• Easypushbuttonset-up,notrequiringtheadjustmentofinternal

orexternalpotentiometers.• Servozero,span,anddirectionoftravelshallbeaccomplished

bypush-buttonconfiguration.• Totallyenclosed,dusttight,andsplash-proofcovers.• Provideaseparatedirectactingdigitalservoactuatorsforthe

fuelgasandfueloil.• Electrically isolated shaft position feedback potentiometer,

integralbrake,90°rotationin25seconds.• Theactuatorshallbecapableofbeingstopped,started,or

instantlyreversedwithoutlossofpoweroroverloading.• Servoactuatorpositioningaccuracy:0.1degrees.Servofull

strokesafestartcheckshallbeprovided.• For high torque applications such aswatertube boiler air

dampers,servotorqueshallberatedminimum70ft-lbswith0.4degreeaccuracy.

• No servo feedback adjustments shall be required withpushbuttonzerosetup.Adjustabletravellimitswitchesshallbeintegral,withre-adjustmentnotrequiringnewfuelairratiocurvere-entry.

• Servos shall be cycledduringeach light-off cycle, and thefeedbackfromeachservomonitoredtoensuresafeactuatoroperation.

• Servos shall bePreferred Instruments,modelBMU-SMorBMU-UM(hightorque).

Documents

BURNERMATE UNIVERSAL BOILER CONTROLLER Overview Instruments/Cont… · Boiler Control Functions Many of the most common boiler control functions are incorporated in the BMU. This