What is SCADA?

An industrial SCADA system will be used for the development of the controls of the four

LHC experiments. This paper describes the SCADA systems in terms of their

architecture, their interface to the process hardware, the functionality and the

application development facilities they provide.

1. Introduction

Widely used in industry for Supervisory Control and Data Acquisition of industrial

processes, SCADA systems are now also penetrating the experimental physics

laboratories for the controls of ancillary systems such as cooling, ventilation, power

distribution, etc.

SCADA systems have made substantial progress over the recent years in terms of

functionality, scalability, performance and openness such that they are an alternative to in

house development even for very demanding and complex control systems as those of

physics experiments.

Types of SCADA

1. D+R+N ( Development +Run + Networking)

2. R+N ( Run +Networking )

3. Factory focus

Features of SCADA

1. Dynamic process Graphic

2. Alarm summery

3. Alarm history

4. Real time trend

5. Historical time trend

6. Security (Application Security)

7. Data base connectivity

8. Device connectivity

9. Scripts

10. Recipe management

Manufacture of SCADA

Modicon (Telemecanique) Visual look

Allen Bradly : RS View

Siemens: win cc

Gefanc:

KPIT : ASTRA

Intelution : Aspic

Wonderware : Intouch

2. What does SCADA MEAN?

SCADA stands for Supervisory Control And Data Acquisition. As the name indicates, it

is not a full control system, but rather focuses on the supervisory level. As such, it is a

purely software package that is positioned on top of hardware to which it is interfaced, in

general via Programmable Logic Controllers (PLCs), or other commercial hardware

modules.

SCADA systems are used not only in industrial processes: e.g. steel making, power

generation (conventional and nuclear) and distribution, chemistry, but also in some

experimental facilities such as nuclear fusion. The size of such plants range from a few

1000 to several 10 thousands input/output (I/O) channels. However, SCADA systems

evolve rapidly and are now penetrating the market of plants with a number of I/O

channels of several 100 K: we know of two cases of near to 1 M I/O channels currently

under development.

SCADA systems used to run on DOS, VMS and UNIX; in recent years all SCADA

vendors have moved to NT and some also to Linux.

3. Architecture

Hardware Architecture

One distinguishes two basic layers in a SCADA system: the "client layer" which caters

for the man machine interaction and the "data server layer" which handles most of the

process data control activities. The data servers communicate with devices in the field

through process controllers. Process controllers, e.g. PLCs, are connected to the data

servers either directly or via networks or fieldbuses that are proprietary (e.g. Siemens

H1), or non-proprietary (e.g. Profibus). Data servers are connected to each other and to

client stations via an Ethernet LAN. The data servers and client stations are NT platforms

but for many products the client stations may also be W95 machines. Fig.1. shows typical

hardware architecture.

Figure 1: Typical Hardware Architecture

Software Architecture

The products are multi-tasking and are based upon a real-time database (RTDB) located

in one or more servers. Servers are responsible for data acquisition and handling (e.g.

polling controllers, alarm checking, calculations, logging and archiving) on a set of

parameters, typically those they are connected to.

Figure 2: Generic Software Architecture

However, it is possible to have dedicated servers for particular tasks, e.g. historian,

datalogger, alarm handler. Fig. 2 shows a SCADA architecture that is generic for the

products that were evaluated.

Communications

Internal Communication

Server-client and server-server communication is in general on a publish-subscribe and

event-driven basis and uses a TCP/IP protocol, i.e., a client application subscribes to a

parameter which is owned by a particular server application and only changes to that

parameter are then communicated to the client application.

Access to Devices

The data servers poll the controllers at a user defined polling rate. The polling rate may

be different for different parameters. The controllers pass the requested parameters to the

data servers. Time stamping of the process parameters is typically performed in the

controllers and this time-stamp is taken over by the data server. If the controller and

communication protocol used support unsolicited data transfer then the products will

support this too.

The products provide communication drivers for most of the common PLCs and widely

used field-buses, e.g., Modbus. Of the three fieldbuses that are recommended at CERN,

both Profibus and Worldfip are supported but CANbus often not [3]. Some of the drivers

are based on third party products (e.g., Applicom cards) and therefore have additional

cost associated with them. A single data server can support multiple communications

protocols: it can generally support as many such protocols as it has slots for interface

cards.

The effort required to develop new drivers is typically in the range of 2-6 weeks

depending on the complexity and similarity with existing drivers, and a driver

development toolkit is provided for this.

Interfacing

Application Interfaces / Openness

The provision of OPC client functionality for SCADA to access devices in an open and

standard manner is developing. There still seems to be a lack of devices/controllers,

which provide OPC server software, but this improves rapidly as most of the producers of

controllers are actively involved in the development of this standardThe products also

provide

• an Open Data Base Connectivity (ODBC) interface to the data in the archive/logs,

but not to the configuration database,

• an ASCII import/export facility for configuration data,

• a library of APIs supporting C, C++, and Visual Basic (VB) to access data in the

RTDB, logs and archive. The API often does not provide access to the product's

internal features such as alarm handling, reporting, trending, etc.

The PC products provide support for the Microsoft standards such as Dynamic Data

Exchange (DDE) which allows e.g. to visualise data dynamically in an EXCEL

spreadsheet, Dynamic Link Library (DLL) and Object Linking and Embedding (OLE).

Database

The configuration data are stored in a database that is logically centralised but physically

distributed and that is generally of a proprietary format.

System (RDBMS) at a slower rate either directly or via an ODBC interface.

Scalability

Scalability is understood as the possibility to extend the SCADA based control system by

adding more process variables, more specialised servers (e.g. for alarm handling) or more

clients. The products achieve scalability by having multiple data servers connected to

multiple controllers. Each data server has its own configuration database and RTDB and

is responsible for the handling of a sub-set of the process variables (acquisition, alarm

handling, archiving).

Redundancy

The products often have built in software redundancy at a server level, which is normally

transparent to the user. Many of the products also provide more complete redundancy

solutions if required.

4. Functionality

4.1 Access Control

Users are allocated to groups, which have defined read/write access privileges to the

process parameters in the system and often also to specific product functionality.

4.2 MMI

The products support multiple screens, which can contain combinations of synoptic

diagrams and text.

They also support the concept of a "generic" graphical object with links to process

variables. These objects can be "dragged and dropped" from a library and included into a

synoptic diagram.

Most of the SCADA products that were evaluated decompose the process in "atomic"

parameters (e.g. a power supply current, its maximum value, its on/off status, etc.) to

which a Tag-name is associated. The Tag-names used to link graphical objects to devices

can be edited as required. The products include a library of standard graphical symbols,

many of which would however not be applicable to the type of applications encountered

in the experimental physics community.

Standard windows editing facilities are provided: zooming, re-sizing, scrolling... On-line

configuration and customisation of the MMI is possible for users with the appropriate

privileges. Links can be created between display pages to navigate from one view to

another.

4.3 Trending

The products all provide trending facilities and one can summarise the common

capabilities as follows:

• the parameters to be trended in a specific chart can be predefined or defined on-

line

• a chart may contain more than 8 trended parameters or pens and an unlimited

number of charts can be displayed (restricted only by the readability)

• real-time and historical trending are possible, although generally not in the same

chart

• historical trending is possible for any archived parameter

• zooming and scrolling functions are provided

• parameter values at the cursor position can be displayed

The trending feature is either provided as a separate module or as a graphical object

(ActiveX), which can then be embedded into a synoptic display. XY and other statistical

analysis plots are generally not provided.

4.4 Alarm Handling

Alarm handling is based on limit and status checking and performed in the data servers.

More complicated expressions (using arithmetic or logical expressions) can be developed

by creating derived parameters on which status or limit checking is then performed. The

alarms are logically handled centrally, i.e., the information only exists in one place and

all users see the same status (e.g., the acknowledgement), and multiple alarm priority

levels (in general many more than 3 such levels) are supported.

It is generally possible to group alarms and to handle these as an entity (typically filtering

on group or acknowledgement of all alarms in a group). Furthermore, it is possible to

suppress alarms either individually or as a complete group. The filtering of alarms seen

on the alarm page or when viewing the alarm log is also possible at least on priority, time

and group. However, relationships between alarms cannot generally be defined in a

straightforward manner. E-mails can be generated or predefined actions automatically

executed in response to alarm conditions.

4.5 Logging/Archiving

The terms logging and archiving are often used to describe the same facility. However,

logging can be thought of as medium-term storage of data on disk, whereas archiving is

long-term storage of data either on disk or on another permanent storage medium.

Logging is typically performed on a cyclic basis, i.e., once a certain file size, time period

or number of points is reached the data is overwritten. Logging of data can be performed

at a set frequency, or only initiated if the value changes or when a specific predefined

event occurs. Logged data can be transferred to an archive once the log is full. The

logged data is time-stamped and can be filtered when viewed by a user. The logging of

user actions is in general performed together with either a user ID or station ID. There is

often also a VCR facility to play back archived data.

4.6 Report Generation

One can produce reports using SQL type queries to the archive, RTDB or logs. Although

it is sometimes possible to embed EXCEL charts in the report, a "cut and paste"

capability is in general not provided. Facilities exist to be able to automatically generate,

print and archive reports.

4.7 Automation

The majority of the products allow actions to be automatically triggered by events. A

scripting language provided by the SCADA products allows these actions to be defined.

In general, one can load a particular display, send an Email, run a user defined

application or script and write to the RTDB.

The concept of recipes is supported, whereby a particular system configuration can be

saved to a file and then re-loaded at a later date.

Sequencing is also supported whereby, as the name indicates, it is possible to execute a

more complex sequence of actions on one or more devices. Sequences may also react to

external events.

Some of the products do support an expert system but none has the concept of a Finite

State Machine (FSM).

5. Application Development

5.1 Configuration

The development of the applications is typically done in two stages. First the process

parameters and associated information (e.g. relating to alarm conditions) are defined

through some sort of parameter definition template and then the graphics, including

trending and alarm displays are developed, and linked where appropriate to the process

parameters. The products also provide an ASCII Export/Import facility for the

configuration data (parameter definitions), which enables large numbers of parameters to

be configured in a more efficient manner using an external editor such as Excel and then

importing the data into the configuration database.

However, many of the PC tools now have a Windows Explorer type development studio.

The developer then works with a number of folders, which each contains a different

aspect of the configuration, including the graphics.

The facilities provided by the products for configuring very large numbers of parameters

are not very strong. However, this has not really been an issue so far for most of the

products to-date, as large applications are typically about 50K I/O points and database

population from within an ASCII editor such as Excel is still a workable option.

On-line modifications to the configuration database and the graphics is generally possible

with the appropriate level of privileges.

5.2 Development Tools

The following development tools are provided as standard:

• a graphics editor, with standard drawing facilities including freehand, lines,

squares circles, etc. It is possible to import pictures in many formats as well as

using predefined symbols including e.g. trending charts, etc. A library of generic

symbols is provided that can be linked dynamically to variables and animated as

they change. It is also possible to create links between views so as to ease

navigation at run-time.

• a data base configuration tool (usually through parameter templates). It is in

general possible to export data in ASCII files so as to be edited through an ASCII

editor or Excel.

• a scripting language

• an Application Program Interface (API) supporting C, C++, VB

• a Driver Development Toolkit to develop drivers for hardware that is not

supported by the SCADA product.

5.3 Object Handling

The products in general have the concept of graphical object classes, which support

inheritance. In addition, some of the products have the concept of an object within the

configuration database. In general the products do not handle objects, but rather handle

individual parameters, e.g., alarms are defined for parameters, logging is performed on

parameters, and control actions are performed on parameters. The support of objects is

therefore fairly superficial.

6. Evolution

SCADA vendors release one major version and one to two additional minor versions

once per year. These products evolve thus very rapidly so as to take advantage of new

market opportunities, to meet new requirements of their customers and to take advantage

of new technologies.

As was already mentioned, most of the SCADA products that were evaluated decompose

the process in "atomic" parameters to which a Tag-name is associated. This is impractical

in the case of very large processes when very large sets of Tags need to be configured. As

the industrial applications are increasing in size, new SCADA versions are now being

designed to handle devices and even entire systems as full entities (classes) that

encapsulate all their specific attributes and functionality. In addition, they will also

support multi-team development.

As far as new technologies are concerned, the SCADA products are now adopting:

• Web technology, ActiveX, Java, etc.

• OPC as a means for communicating internally between the client and server

modules. It should thus be possible to connect OPC compliant third party modules

to that SCADA product.

7. Engineering

Whilst one should rightly anticipate significant development and maintenance savings by

adopting a SCADA product for the implementation of a control system, it does not mean

a "no effort" operation. The need for proper engineering can not be sufficiently

emphasised to reduce development effort and to reach a system that complies with the

requirements, that is economical in development and maintenance and that is reliable and

robust. Examples of engineering activities specific to the use of a SCADA system are the

definition of:

• a library of objects (PLC, device, subsystem) complete with standard object

behaviour (script, sequences, ...), graphical interface and associated scripts for

animation,

• templates for different types of "panels", e.g. alarms,

• instructions on how to control e.g. a device ...,

• a mechanism to prevent conflicting controls (if not provided with the SCADA),

• alarm levels, behaviour to be adopted in case of specific alarms, ...

8. Potential benefits of SCADA

The benefits one can expect from adopting a SCADA system for the control of

experimental physics facilities can be summarised as follows:

• a rich functionality and extensive development facilities. The amount of effort

invested in SCADA product amounts to 50 to 100 p-years!

• the amount of specific development that needs to be performed by the end-user is

limited, especially with suitable engineering.

• reliability and robustness. These systems are used for mission critical industrial

processes where reliability and performance are paramount. In addition, specific

development is performed within a well-established framework that enhances

reliability and robustness.

• technical support and maintenance by the vendor.

For large collaborations, as for the CERN LHC experiments, using a SCADA system for

their controls ensures a common framework not only for the development of the specific

applications but also for operating the detectors. Operators experience the same "look and

feel" whatever part of the experiment they control. However, this aspect also depends to a

significant extent on proper engineering.

WebAccess HMI & SCADA features

Welcome! WebAccess is first fully web browser-based software package for human-

machine interfaces (HMI), and supervisory control and data acquisition (SCADA).

Features of WebAccess include:

Web Browser Client to View and Control

Using a standard Web-Browser (Internet Explorer 6.0 recommended), users

can view and control automation equipment used in manufacturing facilities,

industrial process plants, and building automation systems. Data is displayed

to Operators and Users in real-time with dynamically updated graphics

using full motion animation. A plug-in is required for the full-animation client.

Web Browser based engineering

The unique feature, which distinguishes WebAccess from the competition, is

that all engineering, database configuration, graphics building and software

administration can be performed using a standard web browser as well.

Engineers and Technicians can configure the WebAccess Database and

Build Graphics Remotely using a standard web browser.

Communications Drivers to Industrial Automation Hardware

WebAccess also supplies communications drivers that enable remote personal

computers to communicate with automation hardware including

programmable logic controllers (PLC), IO, controllers, direct digital control

systems (DDC) and distributed control systems (DCS). These drivers are

easily implemented using fill-in-the-blanks forms through an ordinary web

browser.

Distributed Architecture for SCADA node

SCADA nodes run independent of any other node. Each SCADA node

communicates to automation equipment using the communication drivers

supplied with WebAccess. SCADA nodes also provide Alarming, Logs, Reports,

Calculations and other SCADA features. Each SCADA node has its own

graphics displays and a runtime database.

Centralized Database Server for Network Development

The Project Node is a centralized database server of configuration data. A

copy of the database and graphics of all SCADA nodes is kept on the Project

Node. If files are lost from the SCADA node, they are easily downloaded with

a single mouse click.

Remote development features accommodate large, multiple node

installations, including updating of all nodes on a network from a single

location or multiple locations using a web browser.

Ordinary Web Server

WebAccess uses an ordinary web server as our Project Node: Microsoft IIS

(Internet Information Server) or Peer Web Server which are standard in

Windows NT4, 2000 and XP, both Professional and Server versions.

The Project Node provides the initial link between Clients and the SCADA

nodes. Only the Project Node is a Web Server. Redundant Project Nodes

acting as redundant Web Servers are easily implemented. SCADA nodes are

not web servers (except for stand alone installations).

This makes WebAccess a "fully" web-based solution. WebAccess enables

engineers, integrators and vendors with the ability to support their systems

remotely over an intranet or the Internet using an ordinary web browser.

Active X control

WebAccess Client Plug-in is an Active X control that allows it to run inside an

Internet Explorer 5.5 or 6.0 web browser.

Thin Client for PDA and Handheld computers

Similar in function to the full-animation client, the thin client interface

provides snapshots of each display in the GIF and JPEG file formats. Values,

Setpoints and Digital states are changed through a text type interface.

Intended for use on a Windows CE based PDA or handheld computer; any

web browser on any type of PC can view the thin client displays.

Distributed Architecture for SCADA node

SCADA nodes run independent of any other node. Each SCADA node

communicates to automation equipment using the communication drivers

supplied with WebAccess. SCADA nodes also provide Alarming, Logs, Reports,

Calculations and other SCADA features. Each SCADA node has its own

graphics displays and a runtime database.

Centralized Database Server for Network Development

The Project Node is a centralized database server of configuration data. A

copy of the database and graphics of all SCADA nodes is kept on the Project

Node. If files are lost from the SCADA node, they are easily downloaded with

a single mouse click.

Remote development features accommodate large, multiple node

installations, including updating of all nodes on a network from a single

location or multiple locations using a web browser.

Enhanced Security

Users can be assigned various access privileges. WebAccess uses the Area of

Responsibility concept to prevent changes to tags. A tag is assigned to a

single Area with a change level. Users can be assigned to multiple areas with

a different access level within each area. To change a value, the user must

also be assigned to the same Area of Responsibility and have an access Level

within that Area equal to the tags change level.

WebAccess Restricted Users can only view the displays assigned to them.

Push buttons and other features that try to call up an unauthorized display

will be blocked.

Web Access Power Users can view any display, but cannot use the

engineering tool (project manager).

WebAccess Administrators and Project Users are given full control and

database configuration capabilities.

WebAccess Users types are independent of Windows Users.

Tag-based object database

IO Tags are multi-dimensional objects that represent data read from

automation equipment. Tag names can be up to 25 characters. There can be

at least 60,000 tags per SCADA node and many SCADA nodes in a system or

project. Tags consist of multiple fields (Tag Fields) that include Description, Hi

Span, Lo Span, Alarm State, Alarm Limits, Output Limits and about 50 other

qualities associated with each tag.

Blocks

IO Blocks are a type of tag (our competitors call them super tags). Blocks

allow multiple data values read or written from automation devices to be

grouped into a single object. Blocks are most commonly used to represent

PID controllers, VAVs and other multiple value "instruments" found in a

control and automation systems. The typical elements of a PID block include

Measurement, Setpoint and Output of the controller.

Vector-based Graphics

WebAccess uses vector-based graphics that provide smaller file sizes and

faster downloads. Further, vector graphics provide dynamic display resolution

and are continuously scalable. Displays can be run at a user-defined

resolution; independent of the display resolution the graphic was built with.

Engineers and technicians can develop applications in one screen resolution

and users can run them at another.

Dynamic Animation Widgets

The WebAccess Graphic builder provides pre-built symbol libraries including

pre-animated widgets. At least 300 symbols and widgets are in the default

product including pipes, valves, tanks and vessels. Users can easily add

symbols and create widgets from existing scratch or tear a part exiting

graphics.

Import AutoCAD DXF

AutoCAD DXF files can be imported, edited, grouped, filled and animated.

They become vector elements in the graphic that can be infinitely scaled.

Import Bitmaps, Jpegs and Gifs

For flexibility, Bitmaps, JPEGs and GIFs can be imported and animated. They

cannot be edited other than scaling and position. They are not converted to

vectors but remain as bitmaps with all the limitations inherent in bitmap

images.

Template Displays

Template Displays allow all tags to be viewed using one of a few templates.

Pre-built templates displays are supplied with all WebAccess systems and

allow Tags to be viewed immediately without building a single new graphic

The Block detail displays allow a single graphic display, including animation,

to be used to view all blocks tags of the same block type. This dramatically

reduces time to implement a system. Additional Block Tags that are added

the system a viewed instantly without building or modifying a display. Many

drivers come with default block displays for commonly used block types (e.g.

PID controllers, Air Handlers and VAVs). The default Analog Point Display

allows all analog tags to be viewed using this one display

The engineers and technicians using DRAW can edit template displays.

Template displays include Analog Point Detail, Digital Point Detail, Text Point

Detail, Parameter Detail, Block Detail, Data Log Trend, Real Time Trend,

Alarm Log, Action Log and Faceplate Group and Overview displays.

Alarm Handling Package

WebAccess provides a notification system to inform operators of process and

equipment status. Each Tag in the system has alarming which can be enabled

in its database configuration without creating additional tags or logic. Alarms

for each tag include High-High, High, Low, Low-Low, Deviation, Rate of

Change and State alarming. Deadbands are provided for analog alarms.

Features include Alarm Summary of Current Alarms, alarm filtering, alarm

priority, alarm sorting, an Alarm Log of all past alarms, alarm limits

adjustable in run-time, temporary alarm disable, alarm horn, alarm status on

all displays and an Alarm Graphic for each tag in the system to help operators

quickly find the appropriate display and correct the alarm.

Email notification of Alarms is a standard feature in WebAccess. No third party

software is required. Tags can be individually selected to generate an email,

assigned recipient email address or use global email recipients. The scheduler

can schedule different email recipients based on Time of day, shift, Day of

Week, and Holiday schedules.

Data Logging and Historical Trending

Each tag can be logged to a separate file on the SCADA node hard drive.

Historical and Real-time data for the tag are viewed in the Data Log Trend

displays. The traditional strip-chart trending format includes a horizontal time

line, with time stamping, multiple scales for each tag and a cross-hair pointer

to read pinpoint data. Up to 12 tags can be viewed at a time (using a single

window). Tags can be added or removed from the Data Log Trend group

without losing historical data. X-Y plots are also available with a single mouse

click. Scrolling through time and changing scales of displayed data are also

standard features.

Real-Time only Trending

Real-Time Only trending is supported for trends of short-term data that does

not need to be archived. Examples include tuning parameters for controllers

or other seldom viewed information. Real-time Only trends are also useful for

Panel type interfaces or devices where disk space is a premium. Real-time

Only trends loose data once it scrolls off the screen or the display is closed.

Standard Popup Dialog Boxes

System development is made easier and faster by utilizing the standard

Dialog Boxes for user interaction. These boxes are pre-built and popup when

a user tries to change a tag (Change Dialog Boxes, one for Analog, Digital and

Text tags) or request a display list (User Built Displays, Trend Displays, Data

Log Trend Displays, Overview Displays, Faceplate Displays and Alarm Groups.

Change Dialog Box

The standard change dialog box provides the ability to enter data without a

keyboard using numeric buttons (for analog tags), alpha numeric (for text

type displays) and state buttons (for digitals with appropriate state descriptor.

This is especially useful for field mounted display panels using a touch screen

instead of a keyboard. This also speeds system development for users of

touch screen only applications and provides a backup for keyboard users.

Tag Browser (Point Info)

Standard feature in WebAccess Client is a Tag Browser. This is a Windows

Pop-up Dialog Box. It shows all tags in the system. The can be filtered by

Tag Type, IO Channel.

The Tag browser also provides a "Point GOTO" feature that shows all points in

the system where the tag is displayed including all user built graphics, trends,

alarm summary, Detail Displays, etc. With one click you can got to that

display. The Point GOTO feature provides Tag cross-referencing of tags and

displays in the run-time VIEW.

Local Screen Tags

Scripts and Displays support the use of local screen tags to store results, read

operator inputs and create complex calculations with screen scripts. By using

local screen tags in Scripts and Displays you do not decrease your licensed

tag count. There is no limit to the local screen tags in WebAccess.

Internal Tags

Calculation Tags, Accumulation Tags and Constant Tags are globally available.

Calculation tags provide arithmetic and logic calculations, similar to a

programmable calculator that runs repeatedly using inputs from other IO

tags. Accumulation Tags are Totalizers or Integrators (e.g. totalize flow from

flow rate). Constant tags are holder tags used for operator entry or to display

the results of a script. Calculation, Constant and Accumulation Tags are

limited to a number equal to your IO tag count limit (e.g. if you have a 1200

tag limit, you have 1200 IO tags plus 1200 Local Tags = 2400 tags)

Data Transfer Function

Provides an easy to implement method of sending data between automation

equipment. The Data Transfer reads a tag then sends the value to another

tag on a periodic frequency. A deadband can be specified to minimize

unnecessary communication and send changes to the source tag.

Scripts using Tcl

Scripts in WebAccess are based on the open source programming language

Tcl. Web Access supports all version 8.4 built-in Tcl commands and features.

Scripts are simple programs used to customize your displays screens and

SCADA system with user built calculations and logic. Scripts in WebAccess are

powerful enough to communicate with other programs and do control.

If you have any programming experience, you can be writing scripts in 30

minutes. Tcl is an industry standard taught in many schools. You can

download Tcl programs and tutorials from the Internet

ZOOM graphics in Run time

Vector Graphics allow users to zoom in to magnify any display up to a power

of 8x (800 %).

Display Groups

WebAccess local SCADA node supports a non-web browser version intended

for standalone architecture and control room type users. Multiple display

windows can be opened with a single mouse click. Users can save multiple

windows, size, position and default display as a display group, then re-open

this group from a menu list or pushbutton. Other features of display groups

include hide menu bar, no resize and exit password level to close WebAccess.

Navigation Toolbars and right Click menus

Default Navigation Toolbars ensure every display has Navigation, Alarm

Handling and Point Access controls. The default toolbars can be modified or

new toolbars built using symbols, flashing colors and pushbutton keymacro

commands. Right Click Menus enable similar functions as the default toolbars.

Pushbutton Key Macros Commands

Pushbutton Key Macro Commands provide standard control and monitoring

features with a single click including alarm acknowledgment, display

navigation. Many Key Macros have equivalent Keyboard Function Keys that

allow Web Access VIEW to be deployed on systems without a mouse or touch

screen.

Display Scan feature

Display-scan tags are scanned only when an operator calls up the display.

These are usually setpoint, controller tuning and controller configuration"

tags in the controller (i.e. tags that don't change very often and are used

infrequently). By using Display Scan type tags for setpoint, tuning and

infrequently used, "non-alarm points" and "not data logged points" you can

effectively increase the throughput of your system.

100 Millisecond Scan Times

WebAccess can scan as fast as once every 100 milliseconds (ten times per

second). Entering a 0 for scan time, WebAccess will try as fast as possible.

The actual speed depends on the automation device.

Native Drivers

WebAccess provides many Native Drivers that communicate directly to PLCs,

devices and automation networks without using 3rd Party Servers (like DDE

Servers) to provide faster and more reliable communications.

No Charge for Client Licenses

There is no charge for a Client license. This includes VIEW clients that can

view and control in real-time and DRAW, which allows users to build new

graphics and configure a database

No Charge for Configuration Tool (Development)

Any WebAccess system can be copied to another PC and used for off line

development. Every engineer and technician can have is own system on a

laptop for off-line testing and development.

No Charge for Simulation and Training Mode

Any WebAccess system can be copied to another PC and used for Simulation

and Training. Every student can have is own system on a laptop for off-line

training. Tags will initially be set to 50% of SPAN, but can be changed and the

new values held. Alarms will occur; Alarm Logging and all features are

enabled except communications including the device drivers, DDE and 3rd

Party API interfaces. The node will run for 2 hours.

Recipe Function

Recipes provide an easy method for operators and users to change the value

of hundreds of settings in automation devices. Start-up or Shutdown settings

can be downloaded from a single pushbutton and the "recipes" for various

products can be used to "set-up" automation equipment for different product

runs of multiple products.

Data Transfer

Data can easily be exchanged between automation devices using the Data

Transfer function. This is especially useful when data needs to be exchanged

between automation devices that use different communications protocols

(which can't communicate directly) or with "single master" protocols.

DDE interface

Dynamic Data Exchange (DDE) and NetDDE utilize the Microsoft

communications standard to exchange data between your automation

equipment and 3rd Party software packages. WebAccess acts as both a DDE

Server and a DDE Client to interface with spreadsheets, Paging Software and

any software that supports DDE.

DDE Device Driver

A generic DDE Device driver allows any DDE Server based, 3rd Party Device

Driver to be used with WebAccess SCADA node. Dynamic Data Exchange

(DDE) and NetDDE utilize the Microsoft communications standard to exchange

data between your automation equipment and 3rd Party software packages.

Many Automation Vendors supply DDE Server based device drivers that you

can use with WebAccess if there is not a Genuine WebAccess Driver available.

Video

WebAccess provides interfaces to web-enabled Video cameras allowing

operators and users to monitor equipment and facilities using the WebAccess

client. Live full-motion Video cameras, audio and Windows Media are viewed

in same Graphic display as Trends, Alarms, Pushbuttons and Live Data.

Redundant SCADA Nodes

A Redundant SCADA node consists of primary and backup SCADA nodes. The

Project Manager will download an identical run-time database to both primary

and backup SCADA nodes. The Primary and backup will communicate with

each other when the kernel is started, but only one will communicate to

automation hardware. If the Primary fails, the Backup will begin

communications to the automation devices. The Web Browser clients will be

redirected to the backup if the primary node fails. Data Logging and Trending

files are updated on both primary and secondary, and resynchronized when

the Primary returns.

Redundant Com Ports

A Redundant Comport enables a redundant communications path to the

Device. If communications cannot be established through primary Comport,

WebAccess will try a second Comport, specified as the Backup Port. You

configure the backup Port number in WebAccess, but without any devices on

it. Usually the device must have two comports also. The Backup Port is

usually configured as the same type. However, some Device Types allow the

backup port to be another physical type; for example Modicon Device can use

a TCP/IP (network) port as a backup port to a Serial Port.

Scheduler

The Scheduler provides control and setpoint changes based on time and date.

Lights, Fans, and HVAC equipment are turned on and off based on the time,

day of week and date. The Scheduler is also used in process control and

manufacturing applications. The Scheduler can be modified and downloaded

by Project Users from the Project Manager and by Power Users from VIEW.

Email notification of Alarms

Email notification of Alarms is a standard feature in WebAccess. No third party

software is required. Tags can be individually selected to generate an email,

assigned recipient email address or use global email recipients.

Schedule Alarm Email recipients by Shift, Day of Week, and Holidays

The scheduler can schedule different email recipients based on Time of day,

shift, Day of Week, and Holiday schedules.

Email custom reports, logs and Messages

WebAccess can email reports and logs generated with Scripts and Pushbutton

Keymacros.

Customize Toolbars with Icons using ICO or animated BBN files

Standard Microsoft Icon files (*.ico) can be added to user built tool bars.

These can be imported from any application. Toolbars can also be customized

with animation using BBN files built in DRAW to provide flashing, color

change, text changes or any animation.

Import Nodes, Tags and Graphics remotely

WebAccess allows you to import Nodes, Tags, Graphics, Scripts, Keymacro

files and entire databases from a remote node. This allows you to "Merge"

projects by importing to an existing project or the "Split" projects by

importing into a new project. This can be down remotely over the Internet or

intranet to allow field personnel to get the latest version of a project database

or graphics from the Home office.

EXCEL Database Import / Export

The database export and import to EXCEL allow users to create and modify

Tags and Blocks in a spreadsheet using copy, paste, edit and other EXCEL

tools. Databases can be imported from other HMI packages. Tags and Nodes

can be imported from other WebAccess Projects to allow aggregation of

multiple facilities into a larger Project or to scale down and make a node

independent.

System Log

Monitor who connects to the project and SCADA nodes with web browser.

HTML Reports

Generate HTML Reports using menu-based queries of Centralized ODBC Logs

based on Date, Time, Tag, Node including:

· Analog Tag Log

· Discrete Tag Log

· System Log

· Alarm Log

· Action Log

Copy and paste these html reports to EXCEL, Word, etc. support.

automationX minimizes capital expenditures, materia