making a SCADA

Your English is fine. No problem. But I'm not sure what you mean when you say you want to program a SCADA. These things are generally bought as working units. If you are trying to invent your own you can expect to do an awful lot of work to re-invent systems with a long history of development.

Walter.

"Walter Driedger" escribió en el mensaje news:poYWa.620003$ snipped-for-privacy@news1.calgary.shaw.ca... | Your English is fine. No problem.

Thanks!

| But I'm not sure what you mean when you | say you want to program a SCADA.

My idea:

- I have a lot of PLCs and other controllers.

- I have a PC that read/write tags from these PLCs (com1, see below)

- I have a SQL database (I think mySQL is well) that it store all info

- I have a web server (apache) that it serve all sinoptic pages of the plant (or other industry) in html format

- Clients have a web-explorer with Java applets that communicate with the server (com2)

I have this running in a Linux-box with a modbus driver program by me (... MORE DIFICULT !!!! :^D).

| These things are generally bought as | working units.

Sorry, I don't understand you.

| If you are trying to invent your own you can expect to do an | awful lot of work to re-invent systems with a long history of | development.

I don't want to "reinvent the weel", I want to use standard communication in (com1) and (com2) like OPC, but I don't want to pay software (I want to make my "free scada") and I want to use "legal software" (I don't want to crack Kepware or other OPC server). I don't want to remake all drivers to communicate all PLCs (siemens, modicon, hitachi, and so on).

It's my great idea and, I supose, my great dream.

| | Walter.

Thanks for all, Helio.

Run with it Helio! Run!

I mean that SCADA systems are generally bought with all hardware and the associated software as a package. The user simply configures the I/O tables.

"Walter Driedger" escribió en el mensaje news:giZXa.632874$ snipped-for-privacy@news2.calgary.shaw.ca...

| I mean that SCADA systems are generally bought with all hardware and the | associated software as a package. The user simply configures the I/O | tables. |

It's true in a big plant (chemical industry, "automobile industry", ...) Little plants (like "plastic modelling") need a simple software that it communicate with their existent hardware or it implement new functionalities. These plants haven't a lot of money and their propietaries want a cheap software.

Helio, most "Little plants" use HMI's for this kind of thing. You go to one of many suppliers, buy it off-the-shelf, program it to display the parameters you want and plug it in to your PLC.

Have a look at CitectHMI

Cameron:-)

Thanks for all replies.

I worked with Citect and it is a good software. I worked especially with SQL server and visualStudio to make reports from Citect data (through CTAPI, without Plant2SQL).

I still want to develop my software (scada of hmi? buf! does any document explain diferences between scada and hmi? :-P). But my question was if you know a OPC alternative (I find a few doc about "JPC: Java for Process Control" [1] and "DAIS: Data Acquisition from Industrial Systems" [2], can you tell me about they?).

Thanks again, Helio

SCADA involves the communications system. HMI involves the operator interface. Few vendors supply both. Even the DCS folks don't supply communications systems though they do bundle everything else.

Walter.