You are not registered yet. Please click here to register!


 
 
plc storereviewsdownloads
This board is for PLC Related Q&A ONLY. Please DON'T use it for advertising, etc.
 
Try our online PLC Simulator- FREE.  Click here now to try it.

---------->>>>>Get FREE PLC Programming Tips

New Here? Please read this important info!!!


Go Back   PLCS.net - Interactive Q & A > PLCS.net - Interactive Q & A > LIVE PLC Questions And Answers

PLC training tools sale

Reply
 
Thread Tools Display Modes
Old November 8th, 2018, 06:03 PM   #16
OkiePC
Lifetime Supporting Member
United States

OkiePC is offline
 
OkiePC's Avatar
 
Join Date: Mar 2005
Location: ENE of Nowhere Oklahoma
Posts: 9,925
I had to write code for a system with multiple storage tanks, pump stations at various elevations, some of which feed each other, and there were valves. It was a little bit tricky to control everything right and not overpressure certain lines. I had to have different setpoints for the pressure target at one pump station depending on how many valves downstream were open, and I had to have a really long ramp up time (4-6 minutes) during which I ramped the pressure setpoint from the minimum entry to the presently selected target. I also had to condition the logic with the measured flow with shutdown alarm settings for high or low flow. So at least if a line did break, or if a valve stuck shut, the out of range flow rate should indicate that. I was lucky in that the system operator had a good handle on how everything should work, but there were still things that were in his head that didn't quite jive with reality, so a few things had to be edited after commissioning to get it all smoothed out.

The better handle you can get on how the system is laid out up front the better. I highly recommend studying any drawings that exist and creating at least a good sketch if there aren't any or if they are inaccurate.
__________________
It's not all the variables I am most concerned with, it's the undiscovered constants.
  Reply With Quote
Reply
Jump to Live PLC Question and Answer Forum

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Topics
Thread Thread Starter Forum Replies Last Post
AB ControlLogix PID control (gas pressure and flow - 2 valves) BGordon LIVE PLC Questions And Answers 4 May 1st, 2014 01:06 PM
SLC Master Controller PID plcnovel LIVE PLC Questions And Answers 8 July 20th, 2009 01:14 PM
Tag Naming-Name changes-Tracking cntrlfrk LIVE PLC Questions And Answers 2 January 13th, 2009 06:21 PM
Again and again. How to start? Alex Pel LIVE PLC Questions And Answers 33 December 31st, 2004 12:10 PM
Pressure-Position Orn Jonsson LIVE PLC Questions And Answers 5 July 9th, 2002 04:44 PM


All times are GMT -5. The time now is 12:34 AM.


.