FALCON OPC-Server initialisieren

[Kaucher]

Hallo zusammen,

Wer weiß. wie man den EIB-OPC-Server dazu bringt, nach Neustart des Rechners erst mal alle GA selbstandig zu lesen ?

Da er das zur Zeit bei mir nicht tut, bleiben in meiner Visu alle Werte so lange auf 0. bis sie von einem Busteilnehmer gesendet werden.
und das kann dauern... :o

Per Handbedienung kann man die Funktion zwar auslösen, aber automatisch wäre der Hit.

Danke und Gruß

Jörg

[Meudenbach]

Das kann der EIB - OPC von Hause aus nicht. Die Leseanfrage (ValueRead) muss von der Visualisierung an den OPC - Server generiert werden.

Gruss

Mike

[Kaucher]

dann muß ich mal sehen, wie ich das meiner WinCC-Visualisierung beibringe!

Danke Mike !

Gruß Jörg

[Meudenbach]

Ohhhhhh....

wie kommst den an winCC ???
Das ist doch die Prozessvisu von Siemens ???

Ist meines Wissens recht komplex und müsste in jedem Fall funktionieren.

Gruss

[Kaucher]

Hab ich beim Brötchengeber im Einsatz und schon einige Visu's programmiert, allerdings nicht mit OPC sondern mit S5/S7.

Und weil das Teil alles kann, was ich brauche, (und noch viel mehr), hab ich mir halt mal 'ne 128-Variablen-Version geleistet.

man gönnt sich ja sonst nichts....

Gruß Jörg

[S. De Bruyne]

Dear gentlemen,

the EIB OPC server does today not actualise its data when it is started, because of 2 reasons:
a. reading a lot of group values causes a lot of bus traffic (read request + one or multiple answers), and
b. the response from one device is by another device taken as a write, i.e. it updates its CO value. This may lead to unwanted effects.

This is today by-passed by letting some (typically VBA) script within the visualisation software itself access the OPC server and force reading from the bus.

The next OPC server (I hope we have it in a few months) will provide the possibility to read a selected list of group values.

[Meudenbach]

Dear Mr. De Bruyne,

It would be nice if one could configure the polling interval via a variable. This would add additional flexibility and stability in large scale installations.

Additional, the capability of directly editing the project file in ASCII format should be maintained.

Mike

[S. De Bruyne]

Dear Mr. Meudenbach,

these are 2 interesting feature requests.
I have noted them and will check what is possible for integration in the next version.

The OPC specifications do not foresee an OPC server to take itself care of reading its data, so, basically, your request comes down to implement some client functionality in the server. But I'll see what other say, or how this can be supported.

[S. De Bruyne]

Dear Mr. Meudenbach,

maybe I have misunderstood your proposal ... Do you mean you want to configure, when the OPC server starts, the timing when it reads the group addresses (first this one, 5 seconds later that one, ... the last one only 10 minutes later), or do you mean the OPC server should at run-time, during normal operation, also read group values each in a configurable interval?

?

[Meudenbach]

Hi Mr. De Bruyne,

Perhaps I mistyped my request ;)

It would be nice if one could configure the RATE at which the OPC Server reads the group addresses from the bus. This parameter could be set to the desired number of telegrams per second during the initalization of the OPC Server.


When it becomes necessary to restart a single server in large scale installations with multiple OPC Servers (we have an installation with 10), the amount of telegrams on the bus could become exorbitantly high if the READ RATE is not user configurable. Conversly, if the READ RATE is set too high (as a system constant) it could take too long to complete.

Therefore it makes the most sense to allow the system integrator to set this value on a case by case basis, depending on the system architecture, number of data points, the number of opc servers and the typical bus load for the installation.

Does this make more sense ? :)

[S. De Bruyne]

OK, I understand. This of course makes sense.

I'll check with the developers whether this can be controlled in some way.

[Sweden]

Use the OPC-server from Schlaps Automation instead.
It will have the features you need (and more)
http://www.schlaps-automation.de/

To use some VBA-script to force a reading is a stupid idea, when there are better ways around.

[Meudenbach]

Hi Sweden,

First, i use only certficated produkts !!!!

I don´t wrote about using a VBA - script !!!

I think you don´t understand my request....

.... maybe my english is to bad... :(

br

[S. De Bruyne]

a. The OPC specifications do not require that an OPC server initialises its data when being connected, so, the EIB OPC server is fully in line with the OPC requirements when not doing so.
Moreover, as explained, there are good grounds not to do so.

b. The EIB-OPC server gives the quality "bad" for its items at start-up. For a good OPC client this could - under control of the client application - be a reason for asking an active update of the datapoint... As you guess... none of the OPC clients I know uses this feature, so, the fact that some data remains invalid is partly also due to non-implemented functionality in the OPC client!

Please note: OPC is a specification for an electonic data interface; it does not give requirement for the FUNCTIONALITY (i.e. the behaviour) of an OPC server.

But things are being extended from our side, to cope with clients that have little functionality.

[Sweden]

Hi Meudenbach !

I understand the advatage with certified products, it´s a good point.

I´ve been working with both the OPC-server from EIBA and the one from Schlaps.

The advantage with Schlaps is that you can do what you asked for, set the rate for readings of GA:s.
You can also have cyclical readings of selected GA:s and automatic reding on "start-up"

You don´t have to use the functionality, but at least you have an option.

There are also disantvantages with the OPC-server but i have found it very useful.

The VBA-thing was mentioned earlier in this topic. :)