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.

New Here? Please read this important info!!!


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

Reply
 
Thread Tools Display Modes
Old December 19th, 2012, 07:34 PM   #1
termus123
Member
New Zealand

termus123 is offline
 
Join Date: Dec 2012
Location: New Zealand
Posts: 4
How PLC displays tank levels on touch screen graph.

Hi, I'm new to PLCs and my boss kind of forced a project on me regarding PLCs.

I am using a OMRON touch screen, CP1L, CP1W-AD041 and a 8BER

Logically the project is very simple, the ship has 8 ballast tanks to balance the ship, there is a switch for fill, a switch for empty and a stop switch for each of the 8 tanks.

I need to get my PLC to display a graph representation 0-100% of the current water level of its designated tank on the touch screen. To measure the water level I'm using a 4-20mA sensor.

On CX-Designer, the interface was a piece of cake to set up, however, the graphs on there I have no idea how to get that working.

The problem is that I've never touched a PLC or seen one in my life so I can't for the life of me figure out what I need to do in CX Programmer to get that graph working or if I even need to program anything? I'm assuming since the analogue sensor 4-20mAs is detecting the water pressure I need to do something in the CX Programmer to translate that into 0-100%? Or is it going to do that automatically? Where do I start?
Attached Images
File Type: jpg LCMTanksDisplayScreen.jpg (86.1 KB, 107 views)
  Reply With Quote
Old December 19th, 2012, 07:47 PM   #2
mendonsy
Member
United States

mendonsy is offline
 
mendonsy's Avatar
 
Join Date: Feb 2009
Location: Western NY
Posts: 789
The AD041 will produce a value of 0 to 6000 for the 4-20ma input. Those will appear in a CIO address like 002-005 depending on the CP1L model.
If those are Level Meters on your screen you could just scale them 0-6000 and attach them to the CIO address but that only works IF your inputs read 0 when the tank is empty and 6000 if when the tank is full.
  Reply With Quote
Old December 19th, 2012, 07:59 PM   #3
termus123
Member
New Zealand

termus123 is offline
 
Join Date: Dec 2012
Location: New Zealand
Posts: 4
Hi Mendonsy,

Thank you for your swift reply, the exact model of my CP1L is CP1L-EM30DR-D.

I have checked the spec sheet of AD041 prior to your commend and the resolution is as you say 0-6000.

Those are indeed level meters on the screen, my question is how do I scale those meters to 0-6000 but have it displayed in % and which program do I use to do it with? Because the screenshot was done in CX-Designer but shown in the screen below those are the only options I can find for the graph.

Thank you in advance!
Attached Images
File Type: jpg Q2.jpg (72.9 KB, 99 views)
  Reply With Quote
Old December 19th, 2012, 09:05 PM   #4
mendonsy
Member
United States

mendonsy is offline
 
mendonsy's Avatar
 
Join Date: Feb 2009
Location: Western NY
Posts: 789
Probably the easiest solution would be to use the unsigned binary divide instruction (/U) to divide the analog value by 60 and store it in a D register. You can then display the D register directly.
Assuming the data is in 002 your instruction would be something like /U 002 &60 D0.

Last edited by mendonsy; December 19th, 2012 at 09:42 PM. Reason: oops
  Reply With Quote
Old December 20th, 2012, 02:37 PM   #5
termus123
Member
New Zealand

termus123 is offline
 
Join Date: Dec 2012
Location: New Zealand
Posts: 4
Just to provide some addition information,
the ship currently already has a functional non plc/hmi controlled mechanical system with push buttons but they want to upgrade to plc/hmi so they can see a visual representation of the water levels in their ballast tanks.

The PLC's output goes to a relay and from there on it is no longer in my scope as they will be setting it up.

My scope is to get the digital output out and have the HMI interface shown above working with the graph for the water levels working.
  Reply With Quote
Old December 20th, 2012, 02:59 PM   #6
termus123
Member
New Zealand

termus123 is offline
 
Join Date: Dec 2012
Location: New Zealand
Posts: 4
Thanks for the suggestion, seems like what I would end up doing.

Regarding the ladder logic for this, displayed is what I've got so far but I'm not sure what I need to input into the CX Programmer to get the Sensor FULL & Sensor EMPTY to automatically switch off @ 100% & 0% respectively. In addition, my boss tells me that there needs to be a digital output at the end which shoots out some binary stuff which from looking at other examples and reading the manual I've just added 2 coils and gave them an address, that output is going to a relay I think.

If anyone can help me out with what I've got so far I would be most grateful.

Thanks in advance.
Attached Images
File Type: jpg Q4.jpg (54.7 KB, 46 views)
  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
CTC Parker touch screen problem. Elcan LIVE PLC Questions And Answers 4 October 24th, 2014 11:52 AM
PanelView Screen directed by PLC rmb550 LIVE PLC Questions And Answers 5 February 23rd, 2010 02:53 PM
Siemens Touch Screen 670 kimaru LIVE PLC Questions And Answers 0 March 16th, 2008 02:58 AM
MPI comunication Manuel Raposo LIVE PLC Questions And Answers 22 July 16th, 2007 07:24 AM
F940GOT touch screen sutton LIVE PLC Questions And Answers 2 April 29th, 2003 08:38 AM


All times are GMT -4. The time now is 11:06 AM.


.