fieldbus tutorial part 12 - advanced functionality
TRANSCRIPT
Advanced Functionality
[File Name or Event]Emerson Confidential27-Jun-01, Slide 2
Agenda
Process Variability
Commissioning PID
[File Name or Event]Emerson Confidential27-Jun-01, Slide 3
Impact of Reduced Process Variability
Feedstock and Scrap Cost
Productivity
Product Quality
Operating Average ShiftHard Spec.Limit
OperatingAverage
[File Name or Event]Emerson Confidential27-Jun-01, Slide 4
Statistical Process Monitoring
[File Name or Event]Emerson Confidential27-Jun-01, Slide 5
Statistical Process Monitoring
[File Name or Event]Emerson Confidential27-Jun-01, Slide 6
Measurement of Process Variability *
“Capability”
Only Random
or Short Term
Variability
“Total”: All Data
Including Short
and Long Term
Variability
Time
Process
Value
Reference: ‘Achieving Workd Class Manufacturing through
Process Control’ by Joseph Shunta, Dupont, 1995*
[File Name or Event]Emerson Confidential27-Jun-01, Slide 7
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Variability Indicators May be Added To Fieldbus Devices
Total and Capability Standard Deviation is Calculated by I/O and
Control Blocks
[File Name or Event]Emerson Confidential27-Jun-01, Slide 8
Calculation Should be Done at The Fieldbus Device
2.5
2
1.5
1
0.5
0
0 1 2 3 4 5
Stot
SPI
SPID
SLQ
ST/
Ratio of process time constant to sample
time
Source: World Class Manufacturing Through Process Control
[File Name or Event]Emerson Confidential27-Jun-01, Slide 9
Block Parameters for Total and Capability Standard Deviation
[File Name or Event]Emerson Confidential27-Jun-01, Slide 10
Status Indicates: Quality (Good, Uncertain, Bad)
Reason (Device Failure, Sensor Failure, etc.)
Limit (not limited, high limited, Low Limited)
Detecting Abnormal Conditions in Input Blocks
[File Name or Event]Emerson Confidential27-Jun-01, Slide 11
Status Indicates: Quality (Good, Uncertain, Bad)
Reason (Device Failure, Sensor Failure, etc.)
Limit (not limited, high limited, Low Limited)
Detecting Abnormal Conditions in Output Blocks
[File Name or Event]Emerson Confidential27-Jun-01, Slide 12
Status Indicates: Quality (Good, Uncertain, Bad)
Reason (Device Failure, Sensor Failure, etc.)
Limit (not limited, high limited, Low Limited)
Detecting That Control is Limited by Downstream Conditions
[File Name or Event]Emerson Confidential27-Jun-01, Slide 13
Mode Attribute: Target (Operator Requested Mode)
Actual (Mode of operation)
Normal (The designed Mode)
Permitted( Modes that may be selected)
Detecting Incorrect Mode of Operation
[File Name or Event]Emerson Confidential27-Jun-01, Slide 14
Host May Utilize Mode, Status and Statistics
[File Name or Event]Emerson Confidential27-Jun-01, Slide 15
Agenda
Process Variability
Commissioning PID
[File Name or Event]Emerson Confidential27-Jun-01, Slide 16
DistributedApproach
Limited Sample Rate,
Delay/Variation
introduced by
Communications
Traditional,CentralizedApproach
Control &Autotuning
/control & Autotuning
Structuring Control For A Distributed Environment
[File Name or Event]Emerson Confidential27-Jun-01, Slide 17
Application Used For Tuning in Field Device