distributed control systems theory & implementation

ISALunch and Learn

Ken CarfagnoNovember 6, 2013

Agenda

Theory & Practice- Basic control (e.g., regulatory control, feedback, etc)- Discrete control (e.g., relay logic, Boolean algebra) - Sequential control (e g batch)Sequential control (e.g., batch)- Typical Configuration and Programming- Input/output termination and wiring

Implementation - HMI (e.g., graphics, alarm management, trending, historical

data)

2 HONEYWELL - CONFIDENTIAL File Number

- Network security

Basic Control

Types of Control Loops Simple Feedback Control Loop

Control Loop Types & Components

Cascade Control Loops

Components of Control Loops Basic Elements


I P

FR FICFIC FY

Basic Feedback Control Loop

E

FT

FV


E

Most commonly used process control loop

I P

PID Controller

Transducer

Controller Output (0-100%)

Basic Loop Components

PFR FICFIC

E

FY

FT

FV

RecorderTransducer

Primary

Transmitter Final Control Element (control valve)

Pneumatic Signal

Transmission Signal


Element

Detailed description of instrument symbolsare on the legend

Bypass Valve

E Assembly-Double Block/Bleed w Bypass Valve

Block Valve

Block Valve

Control Valve


Bleed Valve

Control Valve

I/P Transducer

TT FICTIC

TRPrimary Controller

Why incorporate a cascade system?

To minimize outside

Cascade Control Loops

I P

FR FICFIC FY

Secondary Controller

To minimize outside load variables resulting in increased process stability

Examples

Condensate control


E

FT

FV Fuel gas/oil burner pressure control

Quick and frequent hydraulic changes

Basic LoopTIC

I/P

TY

TT

Process

Steam

Cascade Control

Condensate

FIC

Load Variable Changes(P1 or P2 is variable)

TICTT

Process


Steam, P1 I/PFY

FT

P2Condensate

Basic Control Implementation Function Blocks

Input from the

Cascade fromPrimary

Input from the transmitter

PID Controller


Output to Valve

Discrete Control

Water level

Float level indicator

Simple Process

Automate simple process Push a button to start The value should open automatically When the valve is open, the pump

should start automatically

INOUT

Valve with actuator

Water level The operator watches the level indicator. When the tank is full the operator pushes another button

The pump should stop and the valve should close.


OUT

Water TankWater Pump

Honeywell Proprietary & ConfidentialHoneywell Proprietary & Confidential

120 VAC

Since I am using relays and pushbuttons to do my remote control, I need an electrical diagram to use as my guide for connecting all of the electrical wires so I create the following pushbutton / relay wiring schematic diagram.

R1

R1

120 VACH N

PB-1PB-2 (Start)(Stop) (Open Valve)

R2

ZSO-2 R1

(Run Pump)(Valve Opened)

R1

120 VACH N

PB-1PB-2

R2

R1

ZSO-2 R1

Here is how it works:

- Press normally open pushbutton PB-2 and relay R1 is energized.

ClosedStopped


R1

120 VACH N

PB-1PB-2

R2

R1

ZSO-2 R1



R1 seals in PB 2 so that when I remove my finger from the button R1 stays energized

OpenStopped


- R1 seals in PB-2 so that when I remove my finger from the button, R1 stays energized.

- A contact from R1 relay is wired to my valve actuator. A closed R1 contact opens the valve. Note R1 is also close in the second rung.

R1

120 VACH N

PB-1PB-2

R2

R1

ZSO-2 R1



R1 seals in PB 2 so that when I remove my finger from the button R1 stays energized

OpenStart


- R1 seals in PB-2 so that when I remove my finger from the button, R1 stays energized.

- A contact from R1 relay is wired to my valve actuator. A closed R1 contact opens the valve. Note R1 is also close in the second rung.

- Valve open contact ZSO-2 is wired from the valve (the contact is closed when the valve is fully open). A closed ZSO-2 contact along with the closed R1 contact energizes relay R2.

- A contact from R2 relay is wired to the pump. A closed R2 contact starts the pump.

R1

120 VACH N

PB-1PB-2

R2

R1

ZSO-2 R1

Once the tank is full, I can stop the pump and close the valve.

Here is how you do it:

OpenStart


- Press normally closed PB-1 and relay R1 is de-energized.

R1

120 VACH N

PB-1PB-2

R2

R1

ZSO-2 R1



Press normally closed PB 1 and relay R1 is de energized

ClosedStopped



- When R1 is de-energized, the contact from R2 stops the pump and the contact from R1 closes the valve.

- Valve open contact ZSO-2 returns to the open state as the valve goes to the closed position.

R1

120 VACH N

PB-1PB-2

R2

R1

ZSO-2 R1



P ll l d PB 1 d l R1 i d i d

ClosedStopped



- When R1 is de-energized, the contact from R2 stops the pump and the contact from R1 closes the valve.

- Valve open contact ZSO-2 returns to the open state as the valve goes to the closed position.

- We are back at the beginning of our sequence when I remove my finger from PB-1.

R1

120 VACH N

PB-1PB-2 R1 Contact

120 VAC

Here is how we would wire our control circuit.

Typical Connection and Wiring

R2

R1

R1

R2 Contact

120 VAC


ZSO-2

Control Via PLC, Ladder Logic

Here is how we would wire our devices to the PLC I/O.

DI DO

DI 1

DI 2

DI 3

DO 1

DO 2

DO 3

PB-1PB-2ZSO 2

PumpValve

PB-1 Stop

DI 3

DI 4

DI 5

DI 6

DI 7

DI 8

DO 3

DO 4

DO 5

DO 6

DO 7

DO 8

ZSO-2


ZSO-2

PB-2 Start

R1

R1

120 VACH N

PB-1PB-2

DI 1

DI 2

DI 3

DI 4

DI 5

DO 1

DO 2

DO 3

DO 4

DO 5

PB-1PB-2ZSO-2

PumpValve

R2

R1 DI 6

DI 7

DI 8

DO 6

DO 7

DO 8

( )DODIDI

ZSO-2 R1

We take all of our wiring information and I/O module information create this program

This is what our PLC programming language looks like.


( )

( )

1

DO

2

DO

1

DI

3

2DO

1

1information create this program.

Notice the relationship between our I/O point numbers and the programming.

R1

R1

120 VACH N

PB-1PB-2

DI 1

DI 2

DI 3

DI 4

DI 5

DO 1

DO 2

DO 3

DO 4

DO 5

PB-1PB-2ZSO-2

Pump

Valve

R2

R1 DI 6

DI 7

DI 8

DO 6

DO 7

DO 8

( )DODIDI

ZSO-2 R1

Also take note that my DI-1 logic contact is normally open. This is because it will be held close by PB-1 when the PLC power is on.


( )

( )

1

DO

2

DO

1

DI

3

2DO

1

1

DI 1

DI 2

DI 3

DI 4

DI 5

DO 1

DO 2

DO 3

DO 4

DO 5

PB-1PB-2ZSO-2

Pump

Valve

R1

R1

120 VACH N

PB-1PB-2

DI 6

DI 7

DI 8

DO 6

DO 7

DO 8

( )DODIDI

R2

R1

ZSO-2 R1

The programming is done on a laptop PC.


( )

( )

1

DO

2

DO

1

DI

3

2DO

1

1

Control via DCS, Function Blocks

R1

R1

120 VACH N

PB-1PB-2

R2

ZSO-2 R1


Sequential Control

Sequential Control

Time ordered control Series of step to meet control objective

- Examples: Equipment Startup or shutdown Equipment Startup or shutdownNon-continuous (batch) process

Sequential Control follows a common pattern- Take action which will cause a change in the process- Wait for the desired change to complete- Repeat


SCM ExampleEmbedded Operator

Instructions

Transition Blocks

Step Blocks


Configured Handlers

Basic Wiring

Analog Inputs

Analog Inputs: Questions

Where does the signal power come from?

Where does the transmitter power come from?

Where is the signal ground?


Analog Inputs, 2 wire, System Powered


AI, Current Signal, Self Power


Human Machine Interface

HMI

HMI Example of Non-Conforming Graphic

PC10615 73

PC10518.70PSIGE209 E210

TI202281.53DEGF TI203

200.09DEGF

FL ARECSR

CW SFUELGAS

FI226400.312MSCFD

PI11510.77PSIG

FI204000.00

MSCFD

T200 FRAC OVRHD

15%

PI20118.71

PSI

TI201280.03

FFC201

4608.23BPD

LC20425%

LI21485%

FC214

FC23413.29KBPD

15.73PSIG

TI21389.03

F

TI223440.06

F

AI241320.78AMPS

D200

T203

T200

C205

LI22495%

VRU

SOUR

CW S

T200 TEMPS1-281.53 DEGF2-280.03 DEGF3-271.89 DEGF4-266.00 DEGF5-255.44 DEGF6-254.99 DEGF7-266.92 DEGF

0%85%

65%


FC2141308.29

BPD

P211

P212P210

P209

NAPHT HA

WTR

SL OP

50%

100%

HMI Example of ASM Graphic


Abnormal Situation Management Study

Comparing ASM designed operator interface (multi-window) vs standard operator interface (single window)- 21 Operators- Matching process upsets on

simulator

>38% improvement in recognizing process deviations before an alarm

26% improvement in their ability to successfully resolveproblem


p 35-48% improvement in overall

operator response time to deviations

Source: ASM Meeting report Oct. 2004

Context-sensitive Access to Information

Context-Sensitive Menus

Alarm helpOperating procedures


Trends and analysis toolsAlarm management toolsMaintenance management tools

Quicker response & Less errors

Alarm Management

Filtering Sorting Alarm Shelving Alarm

CommentingCommenting Custom

Views Alarm Details Links to Detail

& Associated Displays

Alarm Help


p Dynamic Alarm

Suppression

Trending Trending

- Events Integration - Custom Trend - 32 Pens- Resizable views- Save on demand- Improved User Interface- Easy to use time range

selections


Operators can invoke the Location Pane to quickly filter event data to specific process areas.

Operators can invoke the Location Pane to quickly filter event data to specific process areas.

Trending ExamplesTrend Navigation Bar Chart

Trend with Events Trend with Numerics


Secure Network Architectures

Level 4Business Planning

& LogisticsPlant Production Scheduling,

4 - Establishing the basic plant schedule -production, material use, delivery, and shipping. Determining inventory levels.

Ti F

Manufacturing automation architecture

ISA99 functional hierarchical model

FIC

E D

OM

AIN

Level 2

Level 3

Plant Production Scheduling,Operational Management, etc

Manufacturing Operations Management

Dispatching Production, Detailed ProductionScheduling, Reliability Assurance, ...

2 - Monitoring, supervisory control and automated control of the production process

Time Frame

3 - Work flow / recipe control to produce the desired end products. Maintaining records and optimizing the production process.

Time FrameDays, Shifts, hours, minutes, seconds

Time FrameMonths, weeks, days O

FFSS

CO

NTR

OL

DO

MAI

N

ISA9

9


Level 1

BatchControl

DiscreteControl

ContinuousControl

1 - Sensing the production process, manipulating the production process

Time FrameHours, minutes, seconds, subseconds

Level 0 0 - The actual production process

PRO

CES

Typical PCS Network Topology

Firewall

Enterprise Switch

l 3 DMZ

Level 4

Terminal Patch Anti eServer PHD Limited

Comm flow

L4 to L4

Very

Li

mite

d

L3.5

to L

4be

twee

n L4

& L

3

Router

ESC ESF ESTACE ExperionServer

ESVT SafetyManager

TerminalServer

Qualified Cisco Switches

Optional HSRPRouter

Domain Controller

ESF EASPHDServer ExperionServer

3RD Party App SubsystemInterface

Level 3

Level 3.5 DMZ Server MgmtServer

VirusServer

eServerShadowServer

Level 2

Domain Controller

L2 to L2

L3 to L3

Lim

ited

L2 to

L3

Limited L3.5 to L3.5

Very

Li

mite

d L

3 to

L3.

5Ve

ry

Lim

ited

L2

to L

3.5 N

o D

irect

com

mun

icat

ions

or

L2

wee

n L1

& L

3


Qualified Cisco SwitchesLevel 2

Level 1

L1 to L1

Lim

ited

L2 to

L1

No

com

mun

icat

ions

bet

wor

L4

Security levels Level 1 - Controllers and real time control

Level 2 Servers, Operator Stations and supervisory control.

Level 3 - Historians and Advanced Control and connection to other Level 2 areas or units.

Level 3.5 - DMZ accessed from the Business Network and the PCN.

Level 4 - Is the business network with clients for Historians or Advanced Control applications.


Level 3 and 3.5 utilizes standard open systems Ethernet technology and Level 4 utilizes standard open systems LAN technology.

Level 1 Process Control

Domain ESF EASPHD Experion

Firewall

3RD Party App Subsystem

Enterprise Switch

Level 3.5 DMZ

Level 4

TerminalServer

PatchMgmtServer

AntiVirusServer

eServer PHD ShadowServer

Limited L3.5 to L3.5 L3

Comm flow

L4 to L4

Very

Li

mite

d

L3.5

to L

4at

ions

bet

wee

n L4

& L

3

Router


ESVT SafetyManager

TerminalServer


Optional HSRPRouter

Domain Controller

ESF EASServer ExperionServer3RD Party App Subsystem

Interface

Level 3

Level 2

Domain Controller

Level 1 ite

2 to

L2 to L2

L3 to L3

Lim

ited

L2 to

L3

Very

Li

mite

d L

to L

3.5

Very

Li

mite

d L2

to

L3.

5 No

Dire

ct c

omm

unic

aor

L2

s be

twee

n L1

& L

3


Level 1

L1 to L1

Lim

d L2

L1N

o co

mm

unic

atio

nsor

L4

Level 1 - Process Control

Controllers and real time control

Safety Systems Safety Systems

Protected by all other levels


Level 2 Supervisory Control

Firewall

Enterprise Switch

l 3 DMZ

Level 4


Comm flow

L4 to L4

Very

Li

mite

d

L3.5

to L

4be

twee

n L4

& L

3

Router


ESVT SafetyManager

TerminalServer


Optional HSRPRouter

Domain Controller



Level 3


VirusServer

eServerShadowServer

Level 2

Domain Controller

L2 to L2

L3 to L3

Lim

ited

L2 to

L3


Very

Li

mite

d L

3 to

L3.

5Ve

ry

Lim

ited

L2

to L

3.5 N

o D

irect

com

mun

icat

ions

or

L2

wee

n L1

& L

3



Level 1

L1 to L1

Lim

ited

L2 to

L1

No

com

mun

icat

ions

bet

wor

L4

Level 2 - Supervisory Control

Connections for Servers and Operator Stations

Supervisory control

Connection to Level 1

Protection for Level 1 with access lists


FTE capable

Level 3 Advanced Control

Firewall

Enterprise Switch

l 3 DMZ

Level 4


Comm flow

L4 to L4

Very

Li

mite

d

L3.5

to L

4be

twee

n L4

& L

3

Router


ESVT SafetyManager

TerminalServer


Optional HSRPRouter

Domain Controller



Level 3


VirusServer

eServerShadowServer

Level 2

Domain Controller

L2 to L2

L3 to L3

Lim

ited

L2 to

L3


Very

Li

mite

d L

3 to

L3.

5Ve

ry

Lim

ited

L2

to L

3.5 N

o D

irect

com

mun

icat

ions

or

L2

wee

n L1

& L

3



Level 1

L1 to L1

Lim

ited

L2 to

L1

No

com

mun

icat

ions

bet

wor

L4

Level 3 - Advanced Control

Connections for Historians and Advanced Control

Routingg

Access List control

Connect other Level 2 areas or units


Can be redundant, but not FTE capable

HSRP

Level 3.5 Demilitarized Zone (DMZ)

Firewall

Enterprise Switch

l 3 DMZ

Level 4


Comm flow

L4 to L4

Very

Li

mite

d

L3.5

to L

4be

twee

n L4

& L

3

Router


ESVT SafetyManager

TerminalServer


Optional HSRPRouter

Domain Controller



Level 3


VirusServer

eServerShadowServer

Level 2

Domain Controller

L2 to L2

L3 to L3

Lim

ited

L2 to

L3


Very

Li

mite

d L

3 to

L3.

5Ve

ry

Lim

ited

L2

to L

3.5 N

o D

irect

com

mun

icat

ions

or

L2

wee

n L1

& L

3



Level 1

L1 to L1

Lim

ited

L2 to

L1

No

com

mun

icat

ions

bet

wor

L4

Level 3.5 - Demilitarized Zone (DMZ)

Is commonly called the DMZ

Typical nodes WSUS, Anti-Virus Server, etc.

Provides connectivity for devices that are to be accessed from the Business Network and the PCN.

Security zone between the PCN and outside networks


Can be redundant, but not FTE capable

Level 4 - Business Network

Firewall

Enterprise Switch

l 3 DMZ

Level 4


Comm flow

L4 to L4

Very

Li

mite

d

L3.5

to L

4be

twee

n L4

& L

3

Router


ESVT SafetyManager

TerminalServer


Optional HSRPRouter

Domain Controller



Level 3


VirusServer

eServerShadowServer

Level 2

Domain Controller

L2 to L2

L3 to L3

Lim

ited

L2 to

L3


Very

Li

mite

d L

3 to

L3.

5Ve

ry

Lim

ited

L2

to L

3.5 N

o D

irect

com

mun

icat

ions

or

L2

wee

n L1

& L

3



Level 1

L1 to L1

Lim

ited

L2 to

L1

No

com

mun

icat

ions

bet

wor

L4

Level 4 Business Network Is the business network with clients for

Historians or Advanced Control applications.

Untrusted Network

Separated by a firewall

No direct connection to Level 3 or below

Managed by Business IT department

Level 4 utilizes standard open systems LAN


Level 4 utilizes standard open systems LAN technology.

Questions?


Thank You


distributed control systems theory & implementation

Documents

regulatory control

remote control

open pushbutton pb

relay r1

button r1

following pushbutton

relay logic

r1 seals