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DeltaV SIS for BMS ApplicationsDeltaV SIS for BMS Applications
David Sheppard, CFSE
Emerson ConfidentialJune 30, 2009 – Slide 2
By extending the Emerson digital PlantWeb architecture to safety systems, Smart SIS will provide unprecedented customer value by:– enabling safer plants– increasing availability– lowering lifecycle cost– simplifying regulatory compliance
Emerson’s visionEmerson’s vision
Emerson ConfidentialJune 30, 2009 – Slide 3
DEFINITION: SIS(Safety Instrumented System)DEFINITION: SIS(Safety Instrumented System) A SIS
– Takes a process to a safe state when predetermined (dangerous) conditions are violated (e.g. ESD)
– Permits a process to move forward in a safe manner when specified conditions allow (e.g. BMS)
– Takes action to mitigate the consequences of an industrial hazard (e.g. FGS)
Related Definitions• ESD - Emergency Shutdown
• ESS - Emergency Shutdown System
• SSD - Safety Shutdown Systems
• BMS - Burner Management System
• FGS – Fire & Gas Systemshutdown valve
shutdown valve
transmittertransmitter
logic solver
logic solver
Emerson ConfidentialJune 30, 2009 – Slide 4
What is the purpose of a BMS?What is the purpose of a BMS? To inhibit startup when unsafe conditions exist. To protect against the unsafe operating conditions and
admission of improper quantities of fuel to the furnace. To provide the operator with status information – operator
assistance To initiate a safe operating condition or shutdown
interlock if unsafe condition exists. As per NFPA 85, “the BMS is a control system dedicated
to boiler furnace safety and operator assistance……”
Emerson ConfidentialJune 30, 2009 – Slide 5
Why implement BMS in an SIS?Why implement BMS in an SIS? Increased safety Increased system availability Regulatory compliance Potentially lower insurance costs
Emerson ConfidentialJune 30, 2009 – Slide 6
Is BMS a SIS?Is BMS a SIS? Burners, furnaces and boilers are very critical and complex systems. The fact that accidents and disasters are as few as they are, is due to the long
experience has been embodied in various codes and standards. There is evidence that OEMs and end users who wish to comply with standards
(IEC/NFPA), or to meet certain insurance requirements, will have to classify burner management systems as safety-instrumented systems, to achieve certification by a third-party agency.
In the process industry, a BMS is included in the IEC 61511 definition, although not by direct reference. There is also no exclusionary clause.
Burner Management Systems (BMS) are defined as Safety Instrumented Systems (SIS) if they contain sensors, a logic solver and a final control element according to IEC 61511.
All safety critical processes must be analyzed and their potential risk determined. By considering a BMS as a SIS, companies can ensure that these systems are
designed, maintained, inspected and tested per both the applicable prescriptive standards (API, NFPA, etc.) as well as the latest SIS performance-based standards (ANSI/ISA, and IEC).
Emerson ConfidentialJune 30, 2009 – Slide 7
Is a BMS a SIS?Is a BMS a SIS? Six (6) different codes, standards and / or recommended practices have been, or are currently
being developed, that mandate a BMS is a SIS until proven otherwise. – The Black Liquor Recovery Boiler Advisory Committee (BLRBAC) has developed several
guideline documents regarding design and operation of Recovery Boilers in the Pulp and Paper Industry. These documents invoke SIS requirements on the Recovery Boiler BMS.
– FM 7605 – Factory Mutual requires that any PLC listed for use in combustion safeguard service meet the SIS requirements contained in IEC 61508.
– TR84 – The ISA S84 committee has formed a BMS sub-committee to develop a document that clarifies how SIS concepts apply to a BMS. Examples being included in the document for each code or standard are: • NFPA 85 – Single burner boiler• NFPA 86 – Thermal oxidizer• API 14C – Process heater with multiple burners• API 556 – Glycol Reboilers
The goal of the S84 committee is for industrial users to properly follow the safety lifecycle to define the risk of every BMS to determine if it is a SIS.
– NFPA 86 Committee is planning to update this standard to reflect their agreement that an industrial BMS is a SIS and that a safety PLC should be used. It also will refer to ANSI/ISA 84.00.01-2004 as acceptable methodology.
– EN 50156-1 is a European standard covering electrical equipment for furnaces which invokes SIS requirements for a BMS.
– API 556 document governs design of BMS’s in the petroleum industry. It invokes SIS requirements on BMS’s.
Emerson ConfidentialJune 30, 2009 – Slide 8
Burners and boilers are very critical and complex systemsBurners and boilers are very critical and complex systems
Distance of boiler displacement = 50m
DeltaV SIS advanced function blocks simplify configurationDeltaV SIS advanced function blocks simplify configuration IEC 61508 certified modules
and functionality for BMS– Cause and Effect Matrix (CEM)– Step Sequencer– State Transition
Provides very efficient configuration and powerful application software.
Available dynamos and faceplates make the application very transparent for the operator.
Example BMS StatesExample BMS States
S01
S02S03 S04
S06
Shutdown,Not Ready
Shutdown,& Ready
Pre-Purge In progress
Purge Complete
Ignite Pilot
Pilot only Running
Ignite Main with Pilot
Cold Start, Set Low fire
positionS09S10
S12
Main without pilot, not at Temp
Mixed Gas
Mixed firing, set low fire
position
Waste Gas Only
Trips from States5, 6, 7, 8, 9, 10, 12
Startup failure
S05
S07
S08
S13
In order to define a BMS you must know 3 fundamental items.
1. States & Transitions – When to move from one to another 2. Outputs – Valve Positions defined for each State3. Trips – Including which is active during each State
Once these are defined, the DeltaV SIS logic can be programmed inAn easy to follow manner.
The following Example is a Single Burner-Multi Fuel with 13 states:
3 Main Logic Part to a BMS System 3 Main Logic Part to a BMS System
BMS State Transition DiagramBMS State Transition Diagram
S01
S02
1) No Trip condition exists and all trips have been reset
S03
1) Operator initiates Purge hand switch.
S04
1) Total volume flow of nitrogen is confirmed at 200 SCFM for 5 min
1) Operator initiates pilot ignition with hand switch.
S06
1) Pilot flame detected within 15 sec
Shutdown,Not Ready
Shutdown,& Ready
Pre-Purge In progress Purge Complete
Ignite Pilot
Pilot only Running
1) At least 15 seconds elapsed2) At least 6 hours of cold restart time is elapsed OR Operator over-rides this timer.3) Operator initiates "Light Main Burner" hand switch.
Ignite Main with Pilot
Cold Start, Set Low fire position
1) Low fire positions confirmed
S09
1) Flame detectors confirm flame within 15 sec2) Additional 15 sec for flame stabilization
S10
1) Reached min temp
2) Operator initiates hand switch to “Mixed Gas"
S12
1) Low fire positions confirmed
1) Operator initiates “Mixed Gas“ hand switch
1) Operator initiates "Waste Gas Only“ hand switch
Main without pilot, not at Temp
Mixed Gas
Mixed firing, set low fire position
Waste Gas Only
Trips from States5, 6, 7, 8, 9, 10, 12
Startup failure
S05
S07
S08
S13
For Example: To move from State 2 – Shutdown and Ready to State 3 – Pre Purge in Progress The Operator Selects Cold Restart
The Built in DeltaV SIS Function Block - State Transition Block - is used to Easily Define the Transition Logic.
State Transitions – Defines What Allows the Logic to move from one State to Another
Outputs – Defined Per State
Once the States are defined, the position of each Output (Valve, ignitor, etc) is defined in each state in a simple table
State Output Control
Output
Descriptio
n
Descriptio
n
Main natur
al gas
upstream block valve
Main natur
al gas
downstrea
m block valve
Main combustion air valve solenoid #1
Main combustion air valve solenoid #2
Trim combustion air solenoid #1
Trim combustion air solenoid #2
Pilot gas
upstream block valve
Pilot gas
downstrea
m block valve
Waste gas contr
ol valve solenoid 1
Waste gas contr
ol valve solenoid 2
Oxygen to contr
ol valve
Oxygen to contr
ol valve
Oxygen to block valve
Nitrogen to
block valve (FO)
Pilot combustion air valve
Sour Water Gas
Control
Valve Solen
oid
Pilot Ignite
r
Burner
Switch #1 Tunin
g Command
Burner
Switch #2 Tunin
g Command
Tag
XYXXX1-
1
XYXXX2-
2FYXXXX-3
FYXXXY-3
FYXXXY-4
FYXXXX-4
XYXXX1-
5
XYXXX2-
6FYXXXX-7
FYXXXY-7
PXXXX-8
FYXXXX-9
XXXXX-10
XYXXXX-
11
XYXXXX-
12
FYXXXX-13
BYXXXX-
14
BXXXXX1
-15
BXXXXX2
-15
Notes 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
State Name StateD=De-Energize, E=Energize, C=BPCS to hold Closed, R=Release to BPCS Modulation, XX=Set the output % open
Shutdown, Not Ready S01 D D D D D D D D D D D D D D D D D D D
Shutdown & Ready S02 D D D D D D D D D D D D D E D D D D D
Pre Purge in Progress S03 D D D D D D D D D D D D D E D D D D D
Purge Complete S04 D D D D D D D D D D D D D E D D D D D
Ignite Pilot S05 D D D D D D E E D D D D D E E D E D D
Pilot Only Running S06 D D D D D D E E D D D D D E E D D D D
Cold start, set low fire positions S07 D D D D E E E E D D D D D E E D D D D
Ignite main with pilot S08 E E D D E E E E D D D D D E E D D D D
Main NG w/o Pilot, not at temp S09 E E D D E E D D D D D D D D D D D D D
Mixed Gas S10 E E E E E E D D E E D D D D D D D D D
Not Used S11
Mixed firing, set low fire positions S12 D D E E E E D D E E D D D D D D D D D
Waste gas Only S13 D D E E E E D D E E E E E D D E D E E
StatesStates
OutputsOutputs
State Output Control
Output Description
Description
Main
natural gas upstream
block
valve
Main
natural gas downstream bloc
k valv
e
Main
combustion air
valve
solenoid #1
Main
combustion air
valve
solenoid #2
Trim combustion air
solenoid #1
Trim combustion air
solenoid #2
Pilot gas upstream
block
valve
Pilot gas downstream bloc
k valv
e
Waste
gas control
valve
solenoid
1
Waste
gas control
valve
solenoid
2
Oxygen to
control
valve
Oxygen to
control
valve
Oxygen to
block
valve
Nitrogen to bloc
k valv
e (FO)
Pilot combustion air
valve
Sour
Water
Gas Control Valv
e Solenoid
Pilot Igniter
Burner Switch #1
Tuning Command
Burner Switch #2
Tuning Command
Tag
XYXXXX1-1
XY206C2-2
FY2XXXX-3
FY205CY-3
FY212CY-4
FY212CX-4
XY202C1-5
XY202C2-6
FY215CX-7
FY215CY-7
PY237C-8
FY240C-9
XY250C-10
XY224C-11
XY203C-12
FY216C-13
BY217C-14
BX201C1-15
BX201C2-15
Notes 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
State Name StateD=De-Energize, E=Energize, C=BPCS to hold Closed, R=Release to BPCS Modulation, XX=Set the output % open
Shutdown, Not Ready S01 D D D D D D D D D D D D D D D D D D D
Shutdown & Ready S02 D D D D D D D D D D D D D E D D D D D
Pre Purge in Progress S03 D D D D D D D D D D D D D E D D D D D
Purge Complete S04 D D D D D D D D D D D D D E D D D D D
Ignite Pilot S05 D D D D D D E E D D D D D E E D E D D
Pilot Only Running S06 D D D D D D E E D D D D D E E D D D D
Cold start, set low fire positions S07 D D D D E E E E D D D D D E E D D D D
Ignite main with pilot S08 E E D D E E E E D D D D D E E D D D D
Main NG w/o Pilot, not at temp S09 E E D D E E D D D D D D D D D D D D D
Mixed Gas S10 E E E E E E D D E E D D D D D D D D D
Not Used S11
Mixed firing, set low fire positions S12 D D E E E E D D E E D D D D D D D D D
Waste gas Only S13 D D E E E E D D E E E E E D D E D E E The DeltaV SIS logic has a simple matrix that mirrors the table. It drives the outputs blocks
Outputs - Defined per stateOutputs - Defined per state
StatesStates
OutputsOutputs
OutputsOutputsStatesStates
Trips
Trip Input
Description
Description
1 - Loss of main flame signal
2 - Low Natural
Gas Pressur
e
3 - Hi Hi combusti
on air pressure
4 - Low Total
Combustion Air Flow
5 - Hi Hi level in Waste gas KO drum
6 - Hi Hi thermal reactor
temperature
7 - Manual
ESD Button,
RIE
8 - Manual
ESD Button, Local
9 - Hi Hi level in
hydrocarbon
drum 1
10 - Low level in
high pressure stream drum
11 - Hi Hi level
in hydrocar
bon drum 2
12 - Hi Hi level
in hydrocar
bon drum 3
13 - Hi Hi level
in hydrocar
bon drum 4
14 - Loss of
pilot flame signal
15 - Trip on
Software Shutdow
n
TagBSLXXX
1/2PT7XXX
/Y/ZPTXXX1
/2/3
FTXXX1/2/3
FTXXX1/2/3
LTXXXX/Y/Z
TTXXX TTXXXX
HS2XXX2 HSXXX3
LTXXX1/2/3
LTXXX1/2/3
LTXXX1/2/3
LTXXX1/2/3
LTXXX1/2/3 BSLXXX
HSXXXX
Notes
State "T" = Trip, "M"=Mask (no trip)S01 M T T M T T T T T T T T T M TS02 M M T M T T T T T T T T T M TS03 M M T M T T T T T T T T T M TS04 M M T M T T T T T T T T T M TS05 M M T M T T T T T T T T T M TS06 M T T M T T T T T T T T T T TS07 M T T M T T T T T T T T T T TS08 T T T T T T T T T T T T T T TS09 T T T T T T T T T T T T T M TS10 T T T T T T T T T T T T T M TS11 S12 T M T T T T T T T T T T T M TS13 T M T T T T T T T T T T T M T
This cause needs to be “masked” in this state!This cause needs to be “masked” in this state!
This cause has to be able to trip in this state.
This cause has to be able to trip in this state.
Trip Matrix / Appropriate MaskingTrip Matrix / Appropriate MaskingDifferent Trip conditions should be masked during different states. For example, seeing Flame is Required when running, but it must be masked when not running
Trips
Trip Input
Description
Description
1 - Loss of main flame signal
2 - Low Natural
Gas Pressur
e
3 - Hi Hi combusti
on air pressure
4 - Low Total
Combustion Air Flow
5 - Hi Hi level in Waste gas KO drum
6 - Hi Hi thermal reactor
temperature
7 - Manual
ESD Button,
RIE
8 - Manual
ESD Button, Local
9 - Hi Hi level in
hydrocarbon
drum 1
10 - Low level in
high pressure stream drum
11 - Hi Hi level
in hydrocar
bon drum 2
12 - Hi Hi level
in hydrocar
bon drum 3
13 - Hi Hi level
in hydrocar
bon drum 4
14 - Loss of
pilot flame signal
15 - Trip on
Software Shutdow
n
TagBSL201C1/C2
PT729X/Y/Z
PT217C1/2/3
FT205C1/2/3
FT212C1/2/3
LT211X/Y/Z
TT222C TT229C
HS210C2
HS210C3
LT105C1/2/3
LT203C1/2/3
LT625C1/2/3
LT625D1/2/3
LT105D1/2/3
BSL202C
HSXXXX
Notes
State "T" = Trip, "M"=Mask (no trip)S01 M T T M T T T T T T T T T M TS02 M M T M T T T T T T T T T M TS03 M M T M T T T T T T T T T M TS04 M M T M T T T T T T T T T M TS05 M M T M T T T T T T T T T M TS06 M T T M T T T T T T T T T T TS07 M T T M T T T T T T T T T T TS08 T T T T T T T T T T T T T T TS09 T T T T T T T T T T T T T M TS10 T T T T T T T T T T T T T M TS11 S12 T M T T T T T T T T T T T M TS13 T M T T T T T T T T T T T M T
The DeltaV SIS logic has a simple matrix that mirrors the table above that masks conditions based on the state the burner is in
Trips – Including Masking Defined per State
StatesStates OutputsOutputs
This Cause is “masked” in this State!
This Cause is “masked” in this State!
Simple DocumentationSimple Documentation
State Transition Diagram
State Transition Diagram
OutputsOutputs TripsTripsTransitionsTransitions
BMS Trips Graphics – Normal StateBMS Trips Graphics – Normal State
BMS Trips Graphics – Trip StateBMS Trips Graphics – Trip State
BMS Ring of Fire – Step S02BMS Ring of Fire – Step S02
BMS Ring of Fire – Step S06BMS Ring of Fire – Step S06
Emerson ConfidentialJune 30, 2009 – Slide 23
SummarySummary The State Transition Diagram
approach is a very clear and systematic development process:
1. Define the states and transitions.
2. Define the outputs in each state.
3. Define the required trip signals.
4. Define per state if a trip is active or masked.
Very good for developing functional requirements in an interdisciplinary team.
The approach can also be used for other applications.
Emerson ConfidentialJune 30, 2009 – Slide 24
Safety lifecycle benefits:Reduced cost and improved safetySafety lifecycle benefits:Reduced cost and improved safety
Analysis – a well defined approach and easily understandable.
Implementation – can be easily implemented using standard function blocks and dynamos
Operation – because failures can easily be located and removed.
Verification – each state has clearly defined output signals and trip causes which can easily be tested and verified.
Modification – the solution is unambiguous and can easily be modified.
Thank you…Thank you…
…any Questions?