Rslogix 5000 and SQL

How does RSLogix 5000 obtain data from a SQL database? Are certain database variable just sent to the particular PLC, or does the PLC need to have some sort of program to go out and "grab" the data? New to SQL and any information would be greatly appreciated!

There are hardware and software options. For software, there's Rockwell's Factory Talk Transaction Mananger (used to be called RSSql) or the Inductive Automation product.

Hardware, there's eATM tMANAGER inrack card.

I'm sure there are others out there but I'm not familiar with those.

What's the application and does it have to be SQL?

Thank you for the reply!

My application is currently using a SQL database. I have a conveyor line that is supposed to send a random box down a conveyor line. I am told that the database sends a random interval number, in this case its 50, that will dictate when the box is diverted. I'm looking at the program, and I have found the variable RandomInterval contained in a compare instruction. It currently reads zero. I know that the database has the number, but I am unsure where the disconnect lies. Whether it be with the database not sending the variable, the PLC not receiving the variable, or the variable i am looking at coincidentally has the same name as the database variable and they have nothing to do with eachother.

Oh, so it's already talking (you surmise) to a SQL database. I guess you need trace back one step at a time, starting with the PLC to see where that value comes in. Just keep in mind that your assumption of a SQL source may or may not be true. There's a lot of ways to tackle this but I can't really suggest a course of attack unless I know way more information.

There are some HMI that can do simple read/write command to a SQL database as well. I think Wonderware is one of them.