Elipse Knowledgebase

1) Introduction

Elipse SCADA can act as an OPC client and allows that a database created on an OPC server be imported to an internal Elipse SCADA database. Besides, multiple connections can be made, provided they do not use the same OPC server. In this last case, it is possible to access several databases from a server using a single connection.

The OPC technology (OLE for Process Control) implements a mechanism that provides data from a device to a database configured on an OPC server and allows any application to have access to the same database.


Figure 1: Organizer tree displaying the OPCServer item


The connections to OPC servers are added using the OPCServers item on Organizer. When a new connection is added, a new Server item will be created, which displays a configuration page for it. This page displays information like name and item description, and the names of the OPC servers that allow connecting to Elipse SCADA.

When selecting a server, it is possible to import the whole database created on the OPC server or just a part of it.


2) Configuring connection with OPC client


Figure 2: OPC client general configuration page


On the previous figure, you can see the general configuration options of the connection. The OPCServer object has the following attributes and function:

EditProperties(): function that calls the general configuration window of the OPC connection.
name: name of the OPC connection.
description: description of the OPC connection.
recoveryTime: time of OPC recovering.
vrfyTime: time to check the active connection.


3) How to import the database


Figure 3: Import Wizard


The database import window of the OPC server displays all available tags on the right side of the window. This side presents all data from the server as in the OPC server hierarchy. The left side shows the tags already imported to the Elipse SCADA application.

To import the database from the server, it is enough to select the tag or the tag group and drag the selection from the right side to the left side.


4) Configuration of OPC tags

The OPC tags are easily configurable, once imported the tags they already have all information needed to connect to an OPC server. However, it is possible to set the tag reading time and the reading mode, the connection with the server, etc.


OPC tag general configuration window


Figure 4: OPC tag general configuration window


On the previous figure you can see the general configuration options of the OPC tag, with the following attributes:

Name: indicates the tag name for Elipse SCADA.
Description: small description of the tag.
Real Name: indicates to Elipse SCADA what is the tag and where it must be accessed on the OPC server.
Scan: indicates the time in which Elipse SCADA will ask for a reading on the OPC server (it is mandatory only when in synchronous reading).
Read Mode: indicates if the reading on the server will be done in synchronous or assynchronous mode.
Read From: indicates the origin of the tag reading on the OPC server; if device is selected, forces the OPC server to read directly from the device; if cache is selected, receives the last data read by the OPC server.
Enable scan reading: enables automatic reading. Elipse SCADA will ask for new data according to the time defined on Scan field.
Enable automatic writing: enables automatic writing when data is changed.

NOTE: Alarm and bit configurations are made the same way as in PLC tags.