2 Preferred Utilities Manufacturing Corp. IntroductionBurner Management System ObjectivesBMS Design Standards and DefinitionsBMS LogicBMS Strategies and HardwareTypes of Burner Management SystemsBMS Interface to SCADA SystemsSummary
4 Introduction What is a BMS? A Burner Management System is defined as the following:A Control System that is dedicated to boiler safety, operator assistance in the starting and stopping of fuel preparation and burning equipment, and the prevention of mis-operation of and damage to fuel preparation and fuel burning equipment. 11. From NFPA 8501 “Standard for Single Burner Boiler Operation”
5 Burner Management Objectives Sequence burner through safe start-upInsure a complete pre-purge of boilerSupervise safety limits during operationSupervise the flame presence during operationSequence a safe shutdown at end of cycleIntegrate with combustion control system for proper fuel and air flows
6 BMS Design StandardsEach Burner Management System should be designed in accordance with the below listed guidelines to control and monitor all sequences of the start-up and shutdown of the burnerNational Fire Protection Association (NFPA 8501 /8502 or others)Industrial Risk Insurers (IRI)Factory Mutual loss prevention guidelinesEach burner management system should be designed to accomplish a safety shutdown in the event of an unsafe condition. (FAIL SAFE)
7 BMS Design Standards U.S. National Fire Protection Association (NFPA) Governs safety system design on virtually all boilers (regardless of the process to be used to combust the fuel)Requires the separation of the Burner Management System from any other control systemRequires the use of a hardwired backup tripping scheme for microprocessor based systemsRequires that a single failure NOT prevent an appropriate shutdownFactory Mutual loss prevention guidelines.
8 NFPA 8501 NFPA 8501 Standard for Single Burner Boiler Operation Single Burner Boilers with fuel input greater than 12.5 mBTU/Hr (Approx. 250 BHP)Single Fuel or Combination of Fuels (Common being Natural Gas / No.2 Oil / No. 6 Oil)Simultaneous Firing
9 NFPA 8502NFPA 8502 Standard for Prevention of Furnace Explosions / Implosions in Multiple Burner BoilersMultiple Burner Boilers with fuel input greater than 12.5 mBTU/HrSingle Fuel or Combination of Fuels including Pulverized CoalEmphasis on implosion protection (larger boilers with induced draft systems)
10 BMS Definitions Furnace Explosions “Ignition of accumulated combustible mixture within the confined space of a furnace or associated boiler passes, ducts, and fans that convey gases of combustion to the stack”1Magnitude and intensity of explosion depends on relative quantity of combustibles and the proportion of air at the time of ignition1. From NFPA 8502 “Prevention of Furnace Explosions / Implosions in Multiple Burner Boilers”
11 BMS DefinitionsFurnace Explosions can occur with any or a combination of the following:1Momentary loss of flame followed by delayed re-ignitionFuel leakage into an idle furnace ignited by source of ignition (such as a welding spark)Repeated Light-off attempts without proper purgingLoss of Flame on one Burner while others are in operationComplete Furnace Flame-out followed by an attempt to light a burner1. From NFPA 8502 “Prevention of Furnace Explosions / Implosions in Multiple Burner Boilers”
12 BMS Definitions Furnace Implosions More common in large Utility BoilersCaused by any of the following:Malfunction of equipment regulating boiler gas flow resulting in furnace exposure to excessive induced draft fan head capabilityRapid decay for furnace gas temperature and pressure due to furnace trip1. From NFPA 8502 “Prevention of Furnace Explosions / Implosions in Multiple Burner Boilers”
13 BMS Basic Definitions Common Terminology Supervised Manual Manual Burner Lightoff with InterlocksAutomatic Recycling (Single Burner Only)Automatic Burner Start and Stop based on preset operating range (ie.. Drum pressure)Automatic Non Recycling (Single Burner Only)Automatic Burner Start and Stop based on Manual command to start.
14 Types of Flame Scanners Infrared (IR) DetectorsSingle Burner ApplicationsMore Suitable with Oil Burning FlamesUltra-Violet (UV) DetectorsMultiple Burner ApplicationsMore Suitable for Gas Burners and Combination Gas / Oil BurnersSelf Check ScannersFlame Signal is interrupted at set intervals to verify proper operation of scanner
21 BMS System Types Early Burner Management Systems Hardwired SystemsSolid State SystemsMicroprocessor Based SystemsFireye E110 / Honeywell 7800 series with fixed Logic.PLC Based SystemsProgrammable Logic Controller (PLC) BasedPowerful, versatile, expandable, more reliable.
22 Early Burner Management Systems Hardwired SystemsRelay and Timer Driven. Found on older installationsTypical of Late 50’s, 60’sSolid State SystemsSolid State Processors and RelaysFound on Systems provided in the 70’s and 80’sProprietary Hardware (ie.. Forney and Peabody)Spare Parts are extremely hard to find.
23 MicroProcessor Based Systems Microprocessor Based System providing:Burner SequencingIgnitionFlame MonitoringFixed Program with Limited Configuration ChangesComponents Selected Based on RequirementsProgrammers, Flame Amplifiers, Message Displays
25 MicroProcessor Capabilities Simple, Cost EffectiveFeaturesSelectable Flame Amplifiers / ScannersRemote DisplayRemote Data Communications via Modbus PortModernization kits are available to integrate with older systemsSpare Parts Normally Readily Available
26 When These Systems are Used “Simple” Boiler InstallationsPackaged Firetube / Watertube Boilers (Steam / Hot Water)Single BurnerOne Fuel at a TimeNo Flue Gas Re-CirculationUpgrades from Previous MicroProcessor Based Systems
27 PLC Based Burner Management Systems PLC Based FeaturesNFPA 8501, 8502Watchdog timerUL 508 CertificationRedundant ScannersLogic+ Message CenterShows program statusDisplays alarmsPrompts operatorCustom enclosure shown. The annunciator information is also shown on the message center. Optional indications and pushbuttons are shown
28 PLC System Basic Design Features Each PLC based burner management system should incorporate a number of design techniques which help detect and act upon unsafe failure modes which can occur in any microprocessor based system. These design features include the following:Critical Input CheckingCritical output channel monitoringElectro-mechanical Master Fuel Trip (MFT) RelayRedundant Watchdog TimersLow Water Cut-out Monitoring During Blow Down
29 PLC Based System Capabilities Provision for Multiple Fuel FiringCapped gas input during curtailmentChangeover from gas to oil at any loadSimultaneous firing of waste and fossil fuelsRedundant Scanners, change scanner with fuelSingle or Multiple Burner ApplicationsIntegration of BMS with SCADA
30 PLC Based Operator Interfaces FeaturesClear Written Messages to indicate status, required operator interaction, trip/alarm indicationHigh Visibility through two lines of displayMessages reduce time consuming troubleshootingPrioritizes MessagesFirst Out AlarmsWarning / Alarm MessagesStatus Messages / Prompts Operator
32 Benefits of PLC Based Systems Flexibility / ReliabilityProgramming Software allows changes to systemChoice of PLCsGE / Modicon / Allen Bradley / KoyoChoice of Flame ScannersPPC / Fireye / Honeywell / Iris / CoenApplication SpecificQuantity of Burners / Fuels is not restricted
33 When to Use PLC Based Systems “Complex” Boiler InstallationsLarger Packaged Units / Field Erected UnitsMultiple BurnersMultiple Fuels, On-line Fuel ChangeoversFlue Gas Re-CirculationReplace Existing Relay Logic SystemsRequirement to maintain consistent control platform (spare parts, etc..)
34 BMS SCADA Interface BMS Systems can be integrated into a SCADA System Allows Remote Monitoring of Flame StatusAllows Remote Control of BMSEvents (ie.. Burner trip) can be routed to Historical Portion of SCADA for fault evaluationBurner Operation can be trended over time
37 Summary Benefits Associated with New Burner Management Systems Help Improve plant safetyHelp qualify for reduced insurance costReduce Startup and Down Time with comprehensive alarming and diagnostics
38 Summary Review of Topics Discussed Objectives of Burner Management SystemsBMS Design ConsiderationsBasic BMS LogicTypes of Burner Management SystemsHow BMS Systems can be integrated with Plant Wide SCADA Systems
39 Preferred Utilities Manufacturing Corp For further information, contact...Preferred Utilities Manufacturing Corporation31-35 South St. • Danbury • CTT: (203) • F: (203)