High-Tech Operator Certificate Program
Course 1: Treatment and Distribution
Course 1-Day 1
High-Tech Operator Certificate Program
● This course is the first course in a series of three that leads
to a High-Tech Operator Certificate.
● This course addresses the devices used to monitor and
control processes and equipment in water treatment and
distribution systems.
● Course 2: Application and Tools reviews the high-tech tools
available for capturing, creating, finding, and using
information about facilities, assets, and customers.
● Course 3: Data Management provides an overview of the
technologies available for managing information about
assets and process performance.
Copyright © 2009 AWWA
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Agenda Day 1 – Welcome
● Welcome
● Measurement and control symbols, nomenclature, and
drawing conventions
● Sensing devices
● On-line analyzers
● Control devices
● Logic circuits, symbols, and conventions
● Closing and sneak peek at day 2
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Goals
This course covers the basics of process monitoring and control of water
treatment and distribution.
By the end of today, you will be able to:
● Describe the differences and similarities between the three key
diagrams used by high-tech operators
● Discuss the use of analog and discrete sensing devises from a hightech operator perspective
● Communicate the function and value of using on-line analyzers
● Describe at least two control devices used in high-tech operations
● Add new functionality to a loop diagram and explain your perspective
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Getting Acquainted
● How much experience do we have in this room?
● Introduce yourself
● Your name
● Where you work
● Current position
● Number of years working in the water industry
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Ground Rules
● Begin and end on time
● All questions are valid. If you think it, ask
● Respect the opinions of others
● Actively participate
● Today this course is your work; therefore, your full attention is required
– Cell phones on silent
● Break times are scheduled; however, if you need to stand or take a
break before then please do so
● Have fun!
● What other ground rules should we establish?
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Agenda Day 1 – Measurement…
● Welcome
● Measurement and control symbols, nomenclature, and
drawing conventions
● Sensing devices
● On-line analyzers
● Control devices
● Logic circuits, symbols, and conventions
● Closing and sneak peek at day 2
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Measurement and Control Symbols
● Piping and Instrumentation Diagrams (P&ID)
● Shows the interconnection of process equipment and the
instrumentation used to control the process
● Loop Diagrams
● Schematic representation of a complete circuit
● Ladder Logic
● Symbolic representation of a control scheme
● Graphical language for programming Programmable Logic
Controllers (PLC)
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Reading Piping and Instrumentation
Diagrams (P&ID)
● Symbols are simple geometric shapes with text
● Control symbols and process equipment are arranged
conceptually
● Controls and equipment are connected by process and
signal lines
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P&ID – Include
● Instrumentation and designations
● Control inputs and outputs, interlocks
● Mechanical equipment with names and
numbers
● Interfaces for class changes
● All valves and their identifications
● Process piping, sizes, and identification
● Miscellaneous - vents, drains, special
fittings, sampling lines, reducers,
increasers, and swagers
● Permanent start-up and flush lines
● Flow directions
● Interconnections references
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● Seismic category
● Quality level
● Annunciation inputs
● Computer control system input
● Vendor and contractor interfaces
● Identification of components and
subsystems delivered by others
● Intended physical sequence of the
equipment
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P&ID – Don’t include
● Instrument root valves
● Control relays
● Manual switches
● Equipment rating or capacity
● Primary instrument tubing and valves
● Pressure, temperature and flow data
● Elbow, tees and similar standard fittings
● Extensive explanatory notes
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P&ID – Coding and Numbers
First Letter
Subsequent Letters
● Measured Variable
● Readout or Passive Function
●
●
●
●
●
●
●
●
●
Voltage
Flow Rate
Current (Electrical)
Level
Input
Pressure / Vacuum
Speed or Frequency
Temperature
Output
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● Sensor (Primary Element)
● Indicate
● Output Function
● Switch
● Transmit
● Numbering
● Input Nnnn
● Output Xnnn
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P&ID – Decoding Practice
Decoding
Use your workbook to decode the symbols
● Begin with the first letter
● Then decode any subsequent letters to break the code
FE
Flow Rate Sensor
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P&ID – Lines
● Three key lines used in the P&ID
● Main Process Line
● Electrical Signal
● Analog (4-20 mA) Signal
● Line Size
● Size of the line is designated just above the line
36”
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P&ID – Instrumentation Symbols
● Instrument:
Field Mounted
● Instrument:
Panel Door Mounted
● Shared Display
Shared Control
● Programmable Controller
Panel ID
● Flow Meter, Magnetic
● Bubbler Assembly
IA
FE
XX
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MAG
LE
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P&ID – Piping and Mechanical
● Globe Valve
● Motor, General
M
● Check Valve
● Centrifugal Pump
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● Tank or Reservoir Above
Ground
● Tank or Reservoir Below
Ground
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P&ID – Diagram Demo
What symbol & designation would we use to add a pressure sensor in the pump
discharge line?
What symbols & designations would we use to add a pressure indicating
transmitter sending a 4-20mA signal to the PLC?
How would we show that the level indicating transmitter was mounted on a
panel door?
Add a PLC
Add discrete
analog
Add
signals
LIT
1234
M
Add level monitoring
LE
1234
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PIT
1234
FIT
1234
Add flow monitoring
PE
1234
FE
1234
MAG
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P&ID – Modify a P&ID
Edit a P&ID
● At your table, divide into groups of 2-3.
● Each group selects a different P&ID design change request:
● Add a moisture analyzer & indicating transmitter for the air dryer with a
4-20mA signal to the PLC
● Add a pressure sensor & indicating transmitter for the discharge header
with a 4-20mA signal to the PLC
● Add a temperature sensor & indicating transmitter for the discharge
header with a 4-20mA signal to the PLC
● Modify your P&ID accordingly.
● Be prepared to share your completed P&ID.
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Loop Diagrams – Defined
● P&ID applies to the whole process loop.
● Loop diagrams give further information on the control loop
of an individual parameter – an extension of the P&ID.
● Symbolically represents a single control loop identifying
control components and interconnections
● May need a combination of loops on one drawing
● May document electrical or pneumatic instruments or a
combination of both
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Loop Diagrams – Symbols
● Created after the P&ID is completed
● Symbols used for P&ID are suitable for loop diagrams but
are expanded to include
● Connection points
● Power sources
● Instrument actions and ranges
● Safety features
● Balloons connect to P&ID
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Loop Diagram – Explained
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Measurement & Control Symbols
Summary
● What is the difference between a P&ID and Loop diagram?
● At your table list as many distinctions between the two as
you can in five minutes.
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Agenda Day 1: Sensing Devices
● Welcome
● Measurement and control symbols, nomenclature, and
drawing conventions
● Sensing devices
● On-line analyzers
● Control devices
● Logic circuits, symbols, and conventions
● Closing and sneak peek at day 2
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Sensing Devices – Analog & Discrete
● Analog Output Devices
● Continuous detection of flow, level, or pressure
● Meters display measured value
● Varying current between 4 and 20 mA
● Discrete
● Detection of current threshold
● Switches generate a discrete (on/off) signal that recognizes
a high/low process condition
● Combine analog and discrete
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Analog Sensing Devices – Flow
● Control the delivery (both volume and flow)
● Provide control signals
● For automatic or manual adjustment
● For mechanical processes
● Provide flow signals to control flow
● Control valves
● Variable-speed pumps
● Variable unit processes or multiple process units
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Analog Sensing Devices – Flow
● Displacement Meters
● Measure the velocity of flow
● Convert into volume of flow for usage
● Velocity Meters
● Residential and small commercial applications
● Positive Displacement or "PD" meters
● Electromagnetic Meters
● Technically a velocity type water meter
● Uses electromagnetic properties to determine flow velocity
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Analog Sensing Devices – Pressure
● Available to cover a wide range of control
requirements of pneumatic or hydraulic
machines
● Used in control circuits to maintain a
preset pressure requirement
N.O.
● Available in one, two, or more sets of
contacts
● Pressure calibrator is used to calibrate a
pressure switch
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N.C.
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Analog Sensing Devices – Level
● A variety of materials and alloys are used today to combat
harsh environments such as oils, acids, and extremes of
temperature and pressure
● Numerous level sensing devices incorporating numerous
technologies are available
● Used to detect liquid level inside a container or in
its natural form
● Can be either continuous or point values
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Analog Sensing Devices – Level Types
● Point level detection devices
● Floats
● Continuous or point level detection devices
● Capacitance
● Hydrostatic and load cells
● Continuous level detection devices
● Bubbler
● Ultrasound
● Microwave and Radar
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Sensing Devices – Floats
Float Level Monitors
● Floats are mechanical level monitors
● Data can be manually transmitted (line & pulley)
● Data can be electronically transmitted
● Works well for buried tanks
● Upper and lower limits can be measured
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Sensing Devices – Capacitance
● Ability to store an electric charge
● Measures the change in capacitance between
two plates that produce charges in level
● Frequently referred to as RF
for the radio frequency
signals applied to the
capacitance circuit
Insulated
Air
Conductive
medium
K>10
Metal
Tank
Wall
Air
Bare
Nonconductive
medium
(insulating)
Metal tank
wall for
ground
reference
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K<10
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Sensing Devices – Hydrostatic
Hydrostatic Level Monitors and Load Cells
● Indicates water levels and volume, especially when primary
access to the tanks is at the same level as the tank bottom.
● Load cells are electronic devices (transducer) that are used
to convert a force into an electrical signal.
● Properly calibrate for depth, gravity of liquid, temperature,
and/or barometric pressure.
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Sensing Devices – Bubblers
Bubblers
● Pneumatically based air bubbler systems contain no
moving parts
● Bubble tube must be chemically compatible
● Recommended alternative when ultrasound, float, or
Air
microwave devices
have proven undependable
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Sensing Devices – Ultrasound
Ultrasound Level Monitors
● When used in conjunction with humidity and temperature
sensors, or a distance reference:
● Correction factors can be applied to the level measurement
making the technology very accurate
Transmitter
● They do not contact the material
being monitored and have
no moving parts
Transducer
● Output to on-line monitoring
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Sensing Devices – Microwave/Radar
An antenna system guides the microwave down from the top of the tank
to the liquid level and back to the transmitter.
Considered 20 times more efficient than
through-air radar because of the more
focused energy path.
Guided Wave Radar
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Discrete Sensing Devices – Switches
● Flow Switches
● Pressure Switches
● Level Switches
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Sensing Devices – Your Turn
In groups of 3-4 discuss the following
● Which types of level devices do you currently use?
● What problems (if any) have you had with level sensors?
● How were they solved? Were different types of sensors
installed?
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Agenda Day 1 – On-line Analyzers
● Welcome
● Measurement and control symbols, nomenclature, and
drawing conventions
● Sensing devices
● On-line analyzers
● Control devices
● Logic circuits, symbols, and conventions
● Closing and sneak peek at day 2
Copyright © 2009 AWWA
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On-line Analyzers
● Measures physical, chemical, and biological water-quality
parameters
● Measures different variables either simultaneously or
sequentially
● Monitors material content at various stages in flotation or
other mineral-processing flow sheets
● Allows for material balance accounting on a continuous
basis
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On-line Analyzers – Conductivity &
Turbidity
● Conductivity Meters
● Indicate the amount of electrolyte present
● Monitor salt increases and quality changes in river water and
tap water
● Turbidimeters
● Measure the amount of impurities in relatively broad terms
● Used to check the raw, treated, and distributed water
● Used to determine coagulant and coagulant aid automatic
injection rates
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On-line Analyzers - pH & ORP
● pH Analyzers
● Electronically measures electrode potential of a water solution
and directly converts the reading to a pH level
● Determines coagulant aid injection rates and water treatment
process monitoring
● ORP (Oxidation Reduction Potential) Analyzers
● Similar to pH analyzers – some contain a pH electrode as a
reference
● Output signal from the probe is processed by an external
transmitter and sent to the SCADA system or remote display
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On-line Analyzers – Chlorine, Fluoride
& Nutrients
● Residual Chlorine Analyzers
● Provides an exact readout of chlorine present
● Other methods for controlling the addition of chlorine
● Fluoride Analyzers
● Uses the ion-selective electrode (ISE) technique
● Uses an onboard computer to perform all required operations
● Nutrient Analyzers
● Total nitrogen
● Total phosphorous
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On-line Analyzers – Your Turn
Why invest in an on-line analyzer?
Directions:
1.
At your table discuss the above question in relationship to your
work environment.
2.
Define 2-3 reasons why upper management should consider
investing in an on-line analyzer of your choice.
3.
Be prepared to share your suggestions with the class.
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Agenda Day 1- Control Devices
● Welcome
● Measurement and control symbols, nomenclature, and
drawing conventions
● Sensing devices
● On-line analyzers
● Control devices
● Logic circuits, symbols, and conventions
● Closing and sneak peek at day 2
Copyright © 2009 AWWA
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Control Devices –Motor Starter
● Starter characteristics
● Heavy duty relay contains overload protection
● 110 VAC energizes coil that closes the 208, 220, 440, etc.
VAC contacts supplying power to motor
● Energized through push button, relay, or discrete output
(from PLC)
● Two types of starters
● Autotransformer starters
● Solid-state starters
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Control Devices – Speed Control
● Hydraulic Drives
● Pumps, motors, and drives
● Variable Speed Drives (VSD)
● Benefits
● Energy savings
● Improved process control
● Improved reliability
● Drawbacks
● Structural resonance
● Rotor dynamics
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Control Devices - Actuators
● Introduce motion or clamp an object so as to prevent
motion
● Subdivision of transducers
● Transform an input signal (mainly an electrical signal) into
motion
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Control Devices – Controllers and Loops
● Hard-wired, relay-based controllers
● Computer-based controllers
● Single loop
● Multi-loop
● Supervisory set-point
● Distributed network
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Agenda Day 1 – Logic Circuits
● Welcome
● Measurement and control symbols, nomenclature, and
drawing conventions
● Sensing devices
● On-line analyzers
● Control devices
● Logic circuits, symbols, and conventions
● Closing and sneak peek at day 2
Copyright © 2009 AWWA
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Logic Circuits – Ladder Logic
● Method of drawing electrical logic schematics
● Graphical language for programming Programmable Logic
Controllers (PLC)
● Useful for
● Simple but critical control systems
● Reworking old hardwired relay circuits
● Very complex automated systems
● Rule-based language not procedural language
● Each rung on the ladder represents a rule
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Ladder Logic - Pros and Cons
● Best suited for control problems requiring binary variables
● Complex rungs are best broken into simpler steps
● Manufacturers vary in ladder logic languages and may not
be completely compatible
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Ladder Logic - Symbols
● Manual Switches
● Automatic Level Switches
● Indicating Device Symbols
● Relay Symbols
● Timer Relay Symbols
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Ladder Logic - Manual Switches
● Used to make, break, or change connections in a circuit
● Voltage rating required
● Push-button and selector switches most common
● Push-button momentary contact switches make or break
sets of contacts only while pressed
● Selector switches are rotated to different positions to make,
break, or change connections
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Ladder Logic - Push-Button Switches
● Momentary Contact Symbols
Normally Open
Normally Closed
N.C.
N.O.
Maintained Contact
2-single circuit
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1-double circuit
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Ladder Logic - Selector Switches
● Selector Switch Symbols
2-position selector switch
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3-position selector switch
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Ladder Logic - Level Switches
● Level switches are automatic switches used to
● Control fluid levels in processes
● Make or break a circuit when the fluid rises above (or drops
below) a preset level
● Level switches are used in the control circuits of
● Pumps
● Valves
● Alarm indicators
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Ladder Logic - Level Switch Symbols
Normally Open
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Normally Closed
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Ladder Logic - Indicating Device
● Pilot lights are used to provide information about the
operation of the circuit
● Letter inside the symbol indicates light color: G/R
Green/Red
● Lamps inside pilot lights are available in several different
sizes and mounting types
● Available in
● Full voltage and transformer types
● Push-to-test types
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G
Standard pilot light
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Ladder Logic - Relays
● Relays have two significant components:
● A coil which is energized when its circuit is completed.
● One or more sets of contacts which open or close other
circuits.
● Many relays have both N.O. and N.C. contacts.
● Relay symbols
● A relay coil is a circle with its tag or designation inside the
circle.
● The contacts have the same tag or designation as the coil.
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Ladder Logic - Relay Symbols
● Motor Contactor coil
● Control Relay (CR1) coil
M
CR1
● N.O. contacts closed
when CR1 coil is energized
CR1
● N.C. contacts opened
when CR1 coil is energized
CR1
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Ladder Logic - Timer Relays
● A delayed response in making or breaking contacts after the
voltage has been applied to (or removed from) the coil.
● Delay can vary from few seconds to several hours.
● Can be either ON delay timers or OFF delay timers.
N.O.
N.C.
ON delay timer contacts
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N.O.
N.C.
OFF delay timer contacts
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Ladder Logic - Summary
● Ladder diagrams are a common method for describing
control circuits
● A ladder diagram contains information, expressed by
component symbols, about the way the control circuit
functions and in what sequence different events take place
● Ladder diagrams describe the sequence of operation of
circuit, system, or a whole process
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Ladder Logic - Diagram
OFF
L1 HAND AUTO
START
L2
STOP
CR
CR
G
POWER ON
R
POWER OFF
CR
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Ladder Logic – Add a Rung
● Using the diagram in your workbooks, add a rung to the
ladder diagram
● Draw a rung automatically starting on high
● Add an N.O. float switch to energize CR
● Be prepared to discuss what your next addition to this
ladder logic would be
Copyright © 2009 AWWA
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Ladder Logic - Diagram
OFF
L1 HAND AUTO
START
L2
STOP
CR
CR
G
POWER ON
R
POWER OFF
CR
Copyright © 2009 AWWA
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Agenda Day 1 – Closing
● Welcome
● Measurement and control symbols, nomenclature, and
drawing conventions
● Sensing devices
● On-line analyzers
● Control devices
● Logic circuits, symbols, and conventions
● Closing and sneak peek at day 2
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Closing and Sneak Peek at Day 2
● Review
● Tomorrow
● SCADA systems
● Control modes
● Tracking process performance
● Alarm management
● Standards
● Control rooms, environments, enclosures
● Evaluations
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