Same Inputs

dskplc

Member
Join Date
Aug 2013
Location
New Zealand
Posts
119
Hello,
I am new to PLC programming and asking a basic question that stumps me. I have 4 OR function blocks all with the same 2 inputs. Please see attached. How does one prevent the rest of the ORs from activating when you only want the first OR block inputs to be activated? I have struggled with this basic idea in ladder logic also.
Thank you for your help.

SameInputs.jpg
 
Something’s not making sense here. Why do different OR blocks that are tied to different outputs all use the same inputs especially if you don’t want all of the outputs to activate at the same time? Each of the OR function blocks will require a unique input to separate them from each other. The other option would be to put each function block onto a different subroutine.
 
I am going according to a document that is to enable programming from this called a Functional Description. Here is a what I am coding from. Please see my attachment. Thanks. Maybe I am interpreting this wrong.

FD.jpg
 
As there is no ELSE in the conditions specifed, you should be using SET for your outputs, otherwise I agree with your implementation.
 
think of blue when only one fault is present
and green when no fault is present.
see the description coming with the FD.
 

Similar Topics

I've had only rudimentary education in EE so I'm not sure about this setup. I've had 24V discreet I/O have problems in the past when a relay was...
Replies
7
Views
2,169
Hey guys, I'm pretty new to all that PLC stuff. I wonder how I can check wether 2 inputs just became positive. For example, I/0 AND I/1 are on in...
Replies
7
Views
1,653
I am developing logic for our sumps(three)level high alarms using three different level switches. I have terminated these three level switches...
Replies
6
Views
2,713
Hi, I want to build a demo station to test devices and programs and I need some help with it. I want to connect GuardLogix, Piltzmulti and...
Replies
1
Views
149
I am noticing a problem where i am using MOV instruction and writing literal text into source and String datatype in destination. It works fines...
Replies
6
Views
485
Back
Top Bottom