Ladder logic Problem

[dahnuguy]

Why do I want to build a box sorting conveyor all of a sudden?

 

[Clay B.]

Why do I want to build a box sorting conveyor all of a sudden?

Glutton for punishment would be my guess. Bet you like puzzles also..lol

 

[Lancie1]

Lancie problem with part c of your solution is when box 1 at x1 second box is entering x0 so xo and x1 one plc thiks its long box.

Liam, I did NOT intend to give you the entire solution. I was hoping to demonstrate the technique to find and use the bit patterns and let you solve it on your own. For TWO boxes there wil be EIGHT 2-bit patterns generated. For example, for a Short box followed by a Long box (Short-Long):
X0 X1
1__0
0__0
1__0
1__1
1__0
1__1
0__1
0__0
Perhaps your knowledge is not such that you can make the leap to the solution. Here is a WORKING solution (tested it myself) for TWO boxes on the conveyor. For THREE boxes, there will be eight more patterns needed, 4 for the remainder of the first two, and 4 more for the 3rd box (and additional rungs to be added by YOU). The PDF file will be easier to read, except the last 2 rungs are missing!

 

[Liam 28]

Lancie i really apreciate the help you have given me i would never have made the jump to view the boxes as you did . Only new to programming . My problem was i was trying to tell difference between boxes only if x0 and x1 on or if x0 off and x1 off. Now i can see a different method of telling the difference and i learned something . As soon as i started to read it the penny dropped as they say.

 

[Lancie1]

Liam, congratulations, now you know a little bit about pattern recognition. In this case the pattern is only two bits at a time, so it takes a lot of "times", or states, to tell the difference between a long and short box, or a sequence of long and short boxes. You must consider a whole sequence of patterns, enough so that the difference between each possible combination can be picked out and prgrammed.

Somehow you must save the history - what has already passed by, so you know where in the pattern the events are happening. The simplest way is latching bits, although there are better tools and more efficient ways to solve this problem (if you were allowed to use them).

 

[Liam 28]

Ladder Logic problem

Hi all im having a problem up loading a word doc to try and explain a proble i have could some explain how to do this im after trying a couple of times and it says file error each time after i press up load .

 

[Lancie1]

Did you mean "how to upload and attach a Microsoft Word Document (*.doc) to a PLCS.net message?"

If so, here's how:

1. Select "Reply to Thread, write your message, then click "Go Advanced" on bottom menu.
2. On the Advanced Menu, at the bottom again, click "Attach Files".
3. On the Attach Files pop-up, type in the File Path & Name that you wish to attach, or (easier) click one of the Browse buttons and go to the file, then from the Windows "Choose File" menu, click "Open".
4. Now back on the "Attach File" menu, click "Upload". Wait until your selected file is uploaded and shows up in the list of "Current Attachments". You can close the "Attach File" menu then.
5. Now go back on the "Reply to Thread" menu, review your message, make any changes, then click "Submit Reply".
6. Your message will show up, along with the attachment.

The attached file "Program Instructions" is only something to use to generate the above directions.

 

[milldrone]

Hi all im having a problem up loading a word doc

Liam,

Try again. Phil (forum admin) has been upgrading the forum. Perhaps you tried while he was making some changes.

 

[marssram]

good