Integers & floats in ML1400

amitss_sam

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Join Date
Oct 2012
Location
Mumbai
Posts
25
Can you please tell me the relation between N7 integer & F8 floating numbers for ML1400? Purpose of asking is that if I use N7:0, N7:1, N7:2, N7:3 in programme & also if I use F8:0 somewhere in programme then do they interfere?
 
Individual Data Files are limited to 255 elements, so the controller can only have N7:0 through N7:254, and F8:0 through F8:254.

But you can define many additional data files. The first 8 data files with the traditional data types (B3, T4, C5, N7, F8, etc) are automatically created with just one element each when you create a new project.

These data files are expanded automatically when you use a new address from them.

But you can create many additional data files. I'm not certain of the limit.

So you can have N10, N12, F18, F22... anything you like.
 
if these data files are expanded as & when new address is used in programe, then if upto N7:20 are used in programme then there must not be N7:21 & onwards showing in datafile. My previous thread was about seeing PID instructions & PD file, which I cant see from the programme I uploaded from controller to RSlogix 500. But in N7 datafile, I can see integers upto N7:44. Similar is the case for floats. Honestly, is there any system to hide PID instructions & PD file? Because I doubt these integers & floats are there in datafile then they must be used in programme. But I cant see them in programme.
Can you tell me whats wrong here?
 
In RSLogix500 you can set the size of Data Files in their Properties Dialog Window. Many Programmers, if not most, set these Data File sizes based on Program requirements, and envisioned future needs. You can not change the Data File size Online on most AB PLCs, you have to do it Offline, and Download.

You should be able to see any PD Files in the Project Tree Data Files, it should be File 9 or higher. Nothing should be hidden.

If you can't find what you are looking for, Post your RSS File (Zip it First), and we will have a look for you.

Stu.....
 
Please find attached the ladder file. If u see carefully then there are values in datafile which adresses are not used in ladder. Please check & reply. From last 4-5 days I started writing instructions for PID & scaling & other parameters, but then given away as I have doubt that there exist these instructions. If I am 100% sure that there is nothing about PID in programme in controller then I can write the same.
Please confirm that there is nothing for PID. Please check values in datafile for integers & floats. As per my view upto F8:15 are used in ladder. But u can see value there in F8:60
 
Dear Sthompson, with all due respect, I am not expecting magically different answer as if even answer is different then it doesnt be reality if its not true.
In my one reply I already mention my previous thread for PID for finding PID instructions & PD file. That time I didnt seen the value in F8 datafile for which adresses are not used in programme. Thats why I mentioned the same & uploaded programme. My question is in programme if I dont use certain float then i must not have value in datafile for it. & if there is value for it in datafile then it must have been used somewhere in programme. But uploaded programme from controller dont show it. thats why I asked if there is any way to hide some instructions or hide some datafiles or may have password to see them or anything else.
I am never here for adding same file to waste people's valuable time. I am here because I need help which I think experienced people here can help me. My apology if I wasted ur time.
 
All of the F8 Data File is used in the Program, they are used in the Scale Instructions in the PID Subroutine.

Stu....
 
It is not necessary for a data file element to be used.

You could create a data file and never use it at all. Or you could use only a portion of the data file.

The "Usage" view of the Data Files, and the Cross Reference feature are very valuable when you are trying to understand an existing program.
 

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