Open loop flow control scheme

[I_Automation]

In otherwords.....

No, more like:

 

[Levi G]

Hello All

Could we get some expertise on flow control ?

-Using a PID loop in Productivity 2000 with an analog output,
How can we convert that to a relay, open or close to control the flow of product?
We don't have any feedback loop ,just using a pneumatic air cylinder and inching valves
Thanks

If you open the help file within the PID instruction, there is a "timed proportional control" example towards the end.

 

[jdbrandt]

cant speak for all, but in my industry that's exactly what's happened. Most plants cant find qualified technicians and engineers because its long hours, not great pay, call in responsibiites, dirty and dangerous environment, etc. I service about 30 different plants and several contract me to be on call remotely to handle mundane issues.

+1

 

[MaxK]

that's a lot of "somehows" that make it difficult to answer the query from Post #1.

• What does the relay do?
• Is there feedback from the position of whatever final flow-control element (e.g. slide valve) that the inching valve changes?
• Does the inching value control the rate of change of the final flow-control element?
  • If yes, is that rate fixed or variable?
• Can the inching valve either close or open the final flow-control element?
  • Are there multiple inching valves, one opening and one for closing?
  • Or is there one inching valve driven by one relay, and the flow-control element opens more when the relay is activated and closes move when the relay is deactivate?

thanks everyone

Bravo! Best reply ever!!!

 

[robertmee]

No, more like:

I wish....I fix more "fixes" by Technicians than do new work. Don't get me wrong, plenty of Technicians that are quite capable, but in my 35 years, it's on the downhill slide the competency level in factories. Poor Training, long hours, lower headcounts which bring more responsibilities over less time to do them, leads to a half hazard approach to just keep production running. I'm forever removing short circuited branches, AFI's, forced I/O, because they don't fix anything anymore, just bandaid it to keep running.

On the flip side, plenty of incompetent Engineers too. Way too many are comfortable "project managing" now, instead of actually learning the process, talking with operators/maintenance and understanding what's really wrong.