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

or for something with fewer 'bells and whistles' try a Google search on "HMI SCADA' and take your pick.

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

[1]

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.