foxtrot99

When M8029 off ?

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i try to use M8029 to be able run pulse in sequence, i mean i can't use regular PLSY or DPLSY, it doesn't work. So i add M8029 to help clear it and make the plc able to make pulse again. But the problem, when the sequence is finish and i need to start again, plc doesn't give pulse again because the memory that set it on is already reset by M8029. how to set it on again or reset the M8029?

By the way, i'm using FX3U-48MT.

Thanks,I would really appreciate your help.

 

 

ask.jpg

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According to the FX Programming Manual II you need to set a trap to execute the M8029 for each execution.

 

M8029.thumb.png.94c229952bb7c45fde30f7d6

 

Try something like this (Y5 is a general selection, I assume you can use any bit address)

 

M8029a.thumb.png.d9037207353a2248377620b

Edited by Akahige
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add an LDI Y005 RST M1201 rung after this to reset your SET RUN bit...just an after thought.

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1 hour ago, Akahige said:

add an LDI Y005 RST M1201 rung after this to reset your SET RUN bit...just an after thought.

thankyou so much, i'll try that first. one more things, is it a problem when i replace that Y5 with memory (maybe M1202) ?

 

Edited by foxtrot99
additional question

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I do not see using memory bit M1202 being a problem @foxtrot99, the purpose here is to keep the instruction DPLSY active until the execution completes (and triggers M8029). :-2

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Just now, Akahige said:

I do not see using memory bit M1202 being a problem @foxtrot99, the purpose here is to keep the instruction DPLSY active until the execution completes (and triggers M8029). :-2

 

Okey, got it. one more thing, i got this from the FX3U manual, i"m using FX3U 48MT.  Still is it better to use the configuration ( the position of M8029 )  like what you show of me or use in the manual. Is there any different between those two ?

ask.jpg

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Yes, notice in the first example the instruction DSW is triggered by M8000 (always on) so that instruction has time to complete execution because of this and then M8029 triggers when the DSW is done.

On the second rung (similar to the one shown before) the DPLSY instruction may not complete before the next scan so the command input M0 needs to be SET on to assist. Once the execution is done, M8029 triggers and you are back to waiting to SET M0 with you discrete input X0.

The third example, well there is no instruction execution for the M8029 to reference...

Looking at your reference though, you might want to branch your M8029 like it is shown here. I see how this ties that special register to the executing instruction.

Edited by Akahige

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Just now, Akahige said:

Yes, notice in the first example the instruction DSW is triggered by M8000 (always on) so that instruction has time to complete execution because of this and then M8029 triggers when the DSW is done.

On the second rung (similar to the one shown before) the DPLSY instruction may not complete before the next scan so the command input M0 needs to be SET on to assist. Once the execution is done, M8029 triggers and you are back to waiting to SET M0 with you discrete input X0.

The third example, well there is no instruction execution for the M8029 to reference...

 

So basicly it is same with what you already show me ?. it just the placement of M8029 ?. I got a little confusion.

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Just now, Akahige said:

It is. Try something like this:

M8029.thumb.png.a5e1f04e4f0d0182f6687c1a

 

okey i'll try that. But this is what i already try with, it still got problem. The problem is occurs when i restart the system, i mean i turn off the system and try to run it again, it got no memory( all unlatch memory went off ), just like it should be. So when i press some button it should be running again, but nothing happen. The network/line is on, but plc wont pulse again. That x7 and x4 is a proximity switch use for safety, Overtravel and home position,stopping the motor (Y0). I'll try yours, maybe on saturday. Let me ask you again if i still got trouble. Anyway, thank you so much.

ask 2.jpg

Edited by foxtrot99
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I see. When power cycle occurs you do lose the M1201 bit (as it is unlatched) and what I see is that when M1201 is active (assuming a start button) and as long as you are not in home position or over-traveled you request the pulsing of Y0 with whatever frequency stored in D50. And with a restart you lose M1201 so the pulse execution of Y0 is no longer active.

hmm...

The trap might work, but a power cycle also resets all set bits. Please let us know when you try this Saturday. Good luck.

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