CIRCUTOR OPC Server PS-PSS User Manual
COMMUNICATIONS SERVER
PS/PSS OPC Server
Version 1.4
INSTRUCTION M ANUAL
(M98222901-07-13A)
CIRCUTOR S.A.
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CONTENTS
1.- INSTALLATION OF POWERSTUDIO / POWERSTUDIO SCADA OPC SERVER .... 3
2.- OPC (OLE FOR PROCESS CONTROL) .................................................................... 4
3.- POWERSTUDIO / POWERSTUDIO SCADA OPC SERVER ..................................... 4
3.1.- GENERAL DESCRIPTION OF THE SERVER .................................................................... 4
3.2.- SETUP UTILITY......................................................................................................... 4
3.3.- BASIC CONCEPTS .................................................................................................... 5
3.4.- DETAILED OPERATION .............................................................................................. 6
3.5.- STEPS TO ACTIVATE THE OPC SERVER ..................................................................... 6
3.6.- MENU BAR ............................................................................................................ 10
3.6.1.- File menu ...................................................................................................... 10
3.6.2.- OPC Server menu ......................................................................................... 12
3.6.3.- PowerStudio menu ........................................................................................ 15
3.6.4.- Tunnelling menu ........................................................................................... 16
3.6.5.- Help menu ..................................................................................................... 17
3.7.- MAIN SCREEN........................................................................................................ 17
3.7.1.- Connection wit h PowerStudio ....................................................................... 17
3.7.2.- OPC Configuration ........................................................................................ 18
3.7.3.- Get devices ................................................................................................... 19
3.7.4.- Remove server .............................................................................................. 19
3.7.5.- Add devices and variables to OPC server..................................................... 19
3.7.6.- Remove devices and variables from OPC server ......................................... 19
3.7.7.- Establishin g t he acti v e confi g ur ation ............................................................. 19
3.8.- FUNCIONAMIENTO OPC SERVER EN MODO TUNNELLING ........................................... 20
3.9.- TASKBAR MENU ..................................................................................................... 21
3.9.1.- Server state notification................................................................................. 22
4.- TECHNICAL SERVICE ............................................................................................ 22
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1.- I ns tallation of PowerStudio / PowerStudio Scada OPC server
The minimum system requirements needed for the OPC server to work properly on
your PC are:
Windows 2000 SP4
Windows 2003 Server SP1
Windows XP SP2
Windows Vista
1 GB RAM
Pentium 4 3 GHz or Athlon XP 2200
30 MB free space on hard disk
NOTE: The different Windows Service Packs can be downloaded from the official
Microsoft’s web page:
http://www.microsoft.com/downloads/Search.aspx?displaylang=en
In addition to the previous requirements, a broadband internet or local network
connection is recommended since the server makes constant XML requests to
PowerStudio when it is started, thereby considerably increasing network traffic. This is one
of the aspects that will most notably condition the performance of the OPC server.
Once you have checked that your PC meets these requirements, insert the PS/PSS
OPC Server CD.
PowerStudio OPC comes with an installer that takes care of copying all of the
necessary files and configuring the system so that the software works properly.
Installation welcome screen
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2.- OPC (O LE for Process Control)
OPC is a communications standard in the world of process c ontr ol a nd process data
monitoring that allows different data sources to send information to a single server or data
acquisition system which, in turn, can be accessed by different programs that are
compatible with the mentioned standard. In this way, there is no need for each and every
program to have specific drivers to communicate with multiple data sources. They just
need an OPC driver.
To make this communication work, the OPC standard defines a set of protocols,
where each of them has its own particular purpose. The OPC server for PowerStudio and
PowerStudio Scada implements the DA (Data Access) protocol, which is responsible for
the exchange of data in real time between servers and clients.
3.- PowerStudio / PowerStudio Scada OPC Server
In our case, the data source will be PowerStudio SCADA and the OPC server will
make it possible for any OPC-DA client or software which implements it, to access the
values of the variables of the various devices made available in the desired PowerStudio
server.
In order to be able to use the PowerStudio OPC server you must have the HASP
key, or dongle, with the corresponding active licence connected to the PC's USB port. If
this dongle is not available, the server will run in demonstration mode, with the following
limitations:
• 15 minutes of use (after this time the variables will no longer be updated, with
no more requests being made to PowerStudio).
3.1.- General description of the server
The server is based on a Windows service and adds the possibility to commun icate
with the PowerStudio engine via OPC. On the one hand, it handles the variable value
requests from the OPC client and, on the other, it makes the corresponding XML requests
to PowerStudio in order to get the values of the variables that have been requested.
PowerStudio OPC is compatible with versions 1.0, 2.0 and 3.0 of the OPC-DA (Data
Access) specification. It also supports various operating modes which allow its use to be
optimised according to your needs and it is fully configurable through its user interface.
3.2.- Setu p u tility
This is the utility that allows you to configure and manage the PowerStudio OPC
server, setting up all of its operating parameters. This tool also allows you to maintain
various different configuration profiles, offering increased flexibility and adaptability by
giving you the chance to change the behaviour of the server almost in real time. There are
three main aspects that determine the behaviour of the server for each of the created
configurations:
• PowerStudio (data source) connection data
• OPC server configuration
• List of active devices
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3.3.- Basic concepts
In order to better understand this manual and the operation of the PowerStudio /
PowerStudio Scada OPC server, it is necessary to define some concepts:
• Available configurations: The set of all of the different created configurations, which
are saved in *.xml files in the “profiles” folder located in the main application
directory.
• Active configuration: Among all created configurations, one of them must be set as
the active. This will be the one that will determine the OPC server behaviour. The
setup utility allows you to select the active configuration. Whenever the active
configuration is changed, the OPC server is restarted so that it begins to operate
using the new parameters.
• OPC server status: The server can be in any one of the following four different
states: activated, deactivated, started or stopped. We can activate and deactivate
the server from the setup utility, thereby either making it accessible or inaccessible
to OPC clients. If at any moment the server does not detect the presence of the
required dongle in the USB port, it will remain activated but will stop updating the
monitored variables. When the server is active - when it is accessible from any OPC
client - it can either be started or stopped. When a client connects to the server, it
starts up and handles the incoming requests. When there are no clients connected,
the server stops.
• PowerStudio devices: This is the set of all the devices and variables availables on
the PowerStudio server specified in the active configuration.
• OPC devices: This is the set of all the devices and variables accessibles from an
OPC client.
• Update frequency: This is the minimum amount of time that the server will wait
before changing the value of a variable available on it. However, it will always
depend on the update frequenc y of that par ti cular variable in PowerStudio itself.
• Buffer and buffer expiration time: The server has an intermediate memory that
stores the values requested from PowerStudio, arranged by device. These devices
have an associated expiry time. When the value of a device variable is requested
and the values in the buffer for this device have not expired, the value stored in the
buffer is returned. If the buffer values have expired, a request is made to
PowerStudio, updating the values of all the variables in this device. Using the buffer
considerably reduces the number of XML requests carried out. Increasing the
buffer's expiry time is a good way to reduce the strain on system resources.
• Request management method: It determines the way in which the OPC server
makes the XML requests to PowerStudio, according to the OPC client requests it
receives. This is one of the most important configuration parameters since it directly
affects the performance of the OPC server. Selecting the management method that
best suits your needs is essential in order to obtain good results and minimise the
use of system resources. There are 2 available methods:
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o Continual requests: Requests to PowerStudio are made continually,
independently of whether there are incoming OPC requests or not. This
method achieves the best possible response time, reducing update times.
The main disadvantage is that it puts a far greater strain on the system
resources.
o Grouped requests: The requests belonging to the same OPC group are dealt
with together, generating XML requests to PowerStudio only when the
requested variable belongs to a device whose values in the buffer have
expired. To get the best possible performance from this method, you must
create an OPC group for each of the different active devices.
3.4.- Detailed operation
At this point the correct way to use the setup utility to set all of the OPC server's
operating details is explained. First of all, there is a guide for creating an initial
configuration, setting the basic configuration parameters and getting started with the
server as quickly as possible. Afterwards, all of the features of the program are explained
in more detail to enable you to optimise the operation of the server by specifying and
modifying more advanced parameters.
3.5.- Steps to activate the OPC server
The first time you run the application after the installation you will see the following
message, reminding you to create an initial configuration to be able to start up the
PowerStudio OPC server:
Active configuration not set message
In the application's main dialog box, which appears next, you must enter the details
of the connection with PowerStudio and the configuration parameters of the OPC server.
Section 3.5.2 gives a detailed explanation of each of these parameters. For a basic
configuration you only need to complete the following fields:
• “Server” and “Port” with the address and the port of the PowerStudio server
that has to be accessed. If authorization is required, you will also have to fill
in the “Username” and “Password” fields.
• In the “OPC configuration” section, leave the “Optimise the OPC response
time” checkbox selected and set the update time to a value between 2 and 6
seconds, depending on the total number of variables on the server.
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Active devices list contains PowerStudio devices that will be accessible through
OPC. The first time we run the application the list is empty since we haven’t specified any
valid server.
Main application screen
If you try to save the new configuration without having obtained PowerStudio
devices before, the application will display the following message:
Must get devices message
To obtain the devices click the button, located just
below Power Studio connections settings. The application starts look for the enable
devices in the configured engine and notify that the requested action is being carried out
by displaying the following progress window:
Wait process window: getting devices
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