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Unread November 7th, 2019, 07:04 AM   #16
Monty101
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This is the next part of the program. I will write comments ASAP.
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File Type: jpg Bottling plant 1.jpg (57.9 KB, 76 views)
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Unread November 7th, 2019, 07:07 AM   #17
Monty101
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This is how it is supposed to operate:


https://www.youtube.com/watch?v=h9AUaOLwzDE




OP1 (barrier) only raises once in my program, i.e. for the first bottle.



I have written the bottle fixing part and that works perfectly.


Agh!

Last edited by Monty101; November 7th, 2019 at 07:10 AM.
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Unread November 7th, 2019, 08:08 AM   #18
Monty101
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Quote:
Originally Posted by Monty101 View Post
Ladder logic so far. It only fills the first bottle. Can it be fixed?

After the first bottle, in Rung 2,
--F[ ]0--F[/]2--()1


The normally closed switch doesn't get reset for subsequent bottles, I think once opened it stays open.


I think this has something to do with the problem.


If you look at the Youtube identical Youtube ladder program above, it DOES get reset.


Agh!

Last edited by Monty101; November 7th, 2019 at 08:11 AM.
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Unread November 7th, 2019, 09:05 AM   #19
parky
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There are many ways to implement a program and I'm sure many here will come up with many different ways of doing it.
I have attached a pdf with a sample I think may help you it's a step sequence based on your filler, this is only a guide and I'm sure many others will say no you do it like this lol, anyway the program was written in GX works ladder as it probably is quite close to your sim program. The basic idea (as I don't think the info you gave us really gives all the information for example how do you start the process, although you have an output for conveyor 1 how do you start it it's not clear in you description. The program uses step Bits (memory bits/flags whatever you call them) and I have added some timers (long times) as this allows you to follow simulation, on actual program these timers would either be very small or none at all. The step bits are kept on until the end & the outputs are turned back off when required by the following step flags, the step flags are reset at the end of the sequence. Hope this will get you started.
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Unread November 7th, 2019, 10:20 AM   #20
Dryhops
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Quote:
Originally Posted by Monty101 View Post
Thank you, Dryhops.


What do XIC mean? I am using LADSIM and that is not in the software.
These are names for the instructions you are using. Different vendors can use different names. Concept remains the same.

XIC = Normally Open Contact (eXamine If Closed) = ----| |----
XIO = Normally Closed Contact (eXamine If Open) = ---- |/|----
OTE = Output energize, or energize a coil = ----( ) ----
TON = Timer, non retentive
.DN = Bit indicating the timer is finished


Quote:
Originally Posted by Monty101 View Post
After the first bottle, in Rung 2,
--F[ ]0--F[/]2--()1


The normally closed switch doesn't get reset for subsequent bottles, I think once opened it stays open.

Can you watch the logic execute as the program runs in LADSIM? Your ladder is hard to follow without the comments, so I'll wait for those to parse the logic. You're using latching instructions, so I'm guessing the bottle stop is latched and you need to unlatch it once the bottle is full. I don't think you need to use any latching instructions to accomplish this - you certainly can, but it introduces new contingencies you have to manage.

Look at rung 6. You latch F2. It will always stay latched unless you explicitly unlatch it. I don't see any unlatch instructions, so this seems like the source of your problem.

Last edited by Dryhops; November 7th, 2019 at 10:45 AM.
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Unread November 7th, 2019, 11:39 AM   #21
Monty101
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Thank you for taking the time to reply, Parky and Dryhops.


I will try a few alterations to the program based on your observations.



You can watch the logic execute as the program runs in LADSIM here:


https://www.youtube.com/watch?v=h9AUaOLwzDE

Last edited by Monty101; November 7th, 2019 at 11:49 AM.
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Unread November 7th, 2019, 01:04 PM   #22
Monty101
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I have been altering RUNG 6 and running the program:

ORIGINAL Rung 6:


--TN[]DN----F(L)2
------------(Res)




VARIATIONS and impact:

--TN[]DN---- (L)2
------------(Res)

The barrier (OP1) does not lower.



--TN[]DN----F( )2

------------(Res)
The barrier (0P1) partly rises and falls and stops release of the filled bottle.


--TN[]DN---- ( )2

------------(Res)

The barrier (OP1) does not lower.




--TN[]DN----F(L)2


No change to original Rung 6, i.e. only first bottle is filled.
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Unread November 7th, 2019, 01:08 PM   #23
Monty101
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So, altering Rung 6 does not allow Rung 2 -F[]2- to reset after the first bottle is filled.


Agh!
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Unread November 8th, 2019, 12:21 PM   #24
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Agh!
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Unread November 8th, 2019, 05:22 PM   #25
jrwb4gbm
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Based on what you have posted, I see some (L) instructions with no (U) type instructions.
All programming that I have done required for every (L) instruction there was required a (U) type instruction with the same address.
(L) type instructions normally latch and hold until there is an (U) unlatch instruction that releases the (L).
I'm not familiar with LADSIM, so I may be wrong about this.
I downloaded a Demo version of LADSIM and it does seem to be necessary to use the (U) instruction as I pointed out.

Last edited by jrwb4gbm; November 8th, 2019 at 05:40 PM.
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Unread November 8th, 2019, 05:42 PM   #26
janner_10
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In Non-American:

XIC = N/O & XIO = N/C
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Unread November 8th, 2019, 06:29 PM   #27
jrwb4gbm
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In reference to post #25, I personally would recommend avoiding (L) and (U) instructions while you are learning. They have their usage but are difficult for the beginner to fully understand how they react in a program.
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Unread November 9th, 2019, 03:00 AM   #28
Monty101
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Thank you for taking the time to reply janner10 and jrwb4gbm.


The module notes only explain very basic concepts so this is quite challanging.
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Unread November 9th, 2019, 04:03 AM   #29
Monty101
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Dryhops code now works because I now know what XIC AND XIO mean.
Prior to this, I thought they meant the opposite.
Will continue beavering away.


This whole assignement is a big ask given the paucity of the notes.
The final question is controlling a robotic arm using bit shift!
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Unread November 9th, 2019, 06:04 AM   #30
Monty101
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https://www.youtube.com/watch?v=xMxsLKQidY4
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