SattGraph 5000 for Satt DCS

SattGraph 5000 has a completely open software architecture. This is a result of applying established software standards to all interfaces between the different components of the system.

COM and OLE interfaces are provided to make it straightforward for the system integrator to extend the system with special functions. The Configuration database contains all application data for process objects and signals, including alarm and history definitions. Databases for storing of events and alarms, historical recordings and object running time data constitutes a Log Database.

All databases are accessible from any Windows application through ODBC. The system has a true client/server architecture. Multiple operator stations are allowed simultaneous access to the server and one Operator Station may access multiple servers. Automatic reservation mechanisms prevent control hazards, i.e. if two operators try to give orders to the same object at the same time.

Operator access to a process window is obtained through the Process Graphics client. Other client functions available include Reports, Alarm lists, Event lists, History Diagrams, Controller Displays, Running Time Display and Event Viewer. More client functions are easily added using standard Windows applications like Visual Basic, Excel, Access, Word etc.

The Event Viewer can be used in an Operator Station to inspect the Eventlog Database in any of the connected servers.

The alarm handling system in SattGraph 5000 is capable of notifying other applications of an alarm. For instance, the mail system or a telephone paging system could be used to send out messages. The operator may also use the alarm system to invoke other applications. A simple click on an alarm button may, for instance, be used to call up a dialog box with a direct link to a maintenance system.

Historical recording is used to archive values of signals over short and long periods of time. Recorded data may be retrieved and used in existing administrative systems capable of accessing data via ODBC. The recorded values may be viewed in real time or in historical time using the History Diagram component

Communication

SattGraph 5000 includes protocol drivers for OPC Client (OPC 1.0/2.0 Data Access), Comli, SattBus, Modbus RTU, Applicom API and DDE. SattBus can be driven via a SattBus PC board in the PC or via Ethernet (TCP/IP). A driver is supplied for interface to Applicom Server. Applicom Server is a separate product from Applicom International. The Applicom server supports about 30 different protocols for communication with various brands of PLC systems (see Related products). The OPC client supports OPC 1.0/2.0 Data Access for communication variables.

Object Handling

Applications in SattGraph 5000 are built up according to object-oriented design principles. This contributes to the quality of the application software and reduces application programming costs and system maintenance costs.

The Configuration Database in SattGraph 5000 contains an object representation for each supervised process objects in the real world. The configuration database thus supports object orientation, providing support for a structured design and a minimum of engineering time required for an application.

The object orientation principles also make it easy to create a graphical representation of the new object in the process view in SattGraph since the operator interaction part of the object type is handled as a graphical class in the HMI.

An object type may for instance be a pump with a set of properties. When creating a new pump object in the configuration database you can create the new pump object as an instance of the existing pump object type. The pump object will then inherit all the properties from the object type pump since you have reused an already existing object in the system. You don't have to create a new pump object with a set of properties every time you want to add a pump in your application.

Open Systems Overview

SattGraph 5000 is developed for the Microsoft Windows NT TM software environment and makes full use of the Windows COM/DCOM Object Model and functionality. The software architecture is built on established software standards for interfacing the different components of the system. The software bus comprises the following standards.

ODBC (Open DataBase Connectivity) is an interface to commercially available SQL databases.
OLE (Object Link and Embedding) and COM/DCOM (Component Object Model/Distributed COM) are the standard technologies on Windows platforms for implementing support for object-oriented interaction between software components. These technologies provide powerful ways of accessing functions in one component from other software components.
OPC (OLE for Process Control) is an open standard for sharing data from PLCs and other devices with computer applications. It allows applications to read and write process values and enables the data to be easily shared over a computer network.
DDE (Dynamic Data Exchange) is an earlier Windows technology for communication between software components commonly used in many 16-bit implementations. Commercially available DDE drivers support many PLC (Programmable Logic Controller) communication protocols.
MMS (Manufacturing Message Specification) is an ISO standard (ISO 9506) for the application layer in the OSI model for communication between programmable units in an industrial environment. MMS is well suited for rapid exchange of realtime data.
TAPI (Telephony Application Program Interface) is an interface to telephony functions, e.g. controlling a modem. The software bus is extended to other nodes in a network by the use of TCP/IP.

The user can easily integrate functions implemented with standard Windows packages with SattGraph 5000.
Some examples are: 
-- The use of Microsoft Excel for the statistical handling and graphical presentation of collected information.
-- The use of Microsoft Access to produce an application-specific report from collected alarm information.
-- The production formula based ”Management report” with the help of Microsoft Word and saved information.