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 March 13th, 2018, 02:46 PM   #1
sayahan2003
Member
Canada

sayahan2003 is offline
 
sayahan2003's Avatar
 
Join Date: Jun 2006
Location: Calgary
Posts: 179
Question High/Low selector

My friends,

If in an application we have flow control with pressure override, or pressure control with level override or something like this, how do we know that the selector should be low select or high select? Is this related to the controller action (direct or reverse)? what if one of the controller is reverse and the other one is direct? or both direct?

Thanks
  Reply With Quote
Old March 13th, 2018, 04:12 PM   #2
janner_10
Supporting Member
United Kingdom

janner_10 is offline
 
Join Date: Dec 2014
Location: Tewkesbury
Posts: 601
You're gonna have to fix your Google translate or re-phrase that question.

It makes no sense whatsoever.
  Reply With Quote
Old March 13th, 2018, 04:20 PM   #3
sayahan2003
Member
Canada

sayahan2003 is offline
 
sayahan2003's Avatar
 
Join Date: Jun 2006
Location: Calgary
Posts: 179
Quote:
Originally Posted by janner_10 View Post
You're gonna have to fix your Google translate or re-phrase that question.

It makes no sense whatsoever.
you are using the same language for other posts too. If you do not understand, just don't worry about it!
  Reply With Quote
Old March 13th, 2018, 04:21 PM   #4
AustralIan
Member
United Kingdom

AustralIan is offline
 
Join Date: Jan 2013
Location: UK
Posts: 729
You use logic and common sense every time.

"If loop1 wants to drive the output lower and loop 2 wants to drive the output higher, which one would I rather do?"
  Reply With Quote
Old March 13th, 2018, 04:40 PM   #5
boneless
Lifetime Supporting Member + Moderator
United States

boneless is offline
 
Join Date: Feb 2008
Location: OKC
Posts: 1,430
Example from my world.

I want to get a certain temperature (by slowing down flow through a heat exchanger), but I want a minimum flow. Here the highest of the two determines the output.

I want a certain power use on a boiler, but I don't want to exceed my temperature. Here the lowest of the two determines output.
  Reply With Quote
Old March 13th, 2018, 04:40 PM   #6
OkiePC
Lifetime Supporting Member
United States

OkiePC is offline
 
OkiePC's Avatar
 
Join Date: Mar 2005
Location: ENE of Nowhere Oklahoma
Posts: 9,782
The question makes sense, it is just too generalized to get a good response. Maybe you are looking for general answers. Maybe you have some specific hardware that we can apply the question to...
__________________
It's not all the variables I am most concerned with, it's the undiscovered constants.
  Reply With Quote
Old March 13th, 2018, 05:28 PM   #7
sayahan2003
Member
Canada

sayahan2003 is offline
 
sayahan2003's Avatar
 
Join Date: Jun 2006
Location: Calgary
Posts: 179
Quote:
Originally Posted by boneless View Post
Example from my world.

I want to get a certain temperature (by slowing down flow through a heat exchanger), but I want a minimum flow. Here the highest of the two determines the output.

I want a certain power use on a boiler, but I don't want to exceed my temperature. Here the lowest of the two determines output.
Thanks boneless,
Your example are absolutely correct. My question is how you get to the result at the last sentence of each example(lowest or highest).
  Reply With Quote
Old March 13th, 2018, 05:29 PM   #8
sayahan2003
Member
Canada

sayahan2003 is offline
 
sayahan2003's Avatar
 
Join Date: Jun 2006
Location: Calgary
Posts: 179
Quote:
Originally Posted by OkiePC View Post
The question makes sense, it is just too generalized to get a good response. Maybe you are looking for general answers. Maybe you have some specific hardware that we can apply the question to...
Thanks OkiePC,

This is a general question. I don't have a specific hardware.
  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
3 pos selector switch schematic notation david90 LIVE PLC Questions And Answers 3 November 20th, 2012 05:30 PM
recipe plus selector - number of characters italo2008 LIVE PLC Questions And Answers 0 February 22nd, 2012 06:33 AM
FTview ME. question about recipe plus selector object italo2008 LIVE PLC Questions And Answers 0 February 1st, 2012 07:21 AM
screen change and screen locked from selector switch - proface icekalt LIVE PLC Questions And Answers 1 April 6th, 2011 03:43 AM
14 Wire Selector Switch The Plc Kid LIVE PLC Questions And Answers 20 January 4th, 2010 11:17 AM


All times are GMT -5. The time now is 08:33 AM.


.