BJR

Thank you all for the suggestions.  I will not have time to make improvements for a week or two but appreciate the lessons! 

I suspected that the answer would depend on something but didn't know enough where to look for any related options or parameters.  Thanks for the response.  I will check out the MAM setup for those two moves...

I am going over someone else's program making a few changes and double checking what they did.  I always use .PC to determine when an MAM has completed.  He has used some LIM commands corresponding to finding a small limit around the .actualPosition and comparing what the commanded position was which is probably OK too. But then I ran across what seems to be one move followed by another move in the other direction and nothing really being monitored to know when to make the second MAM other than a small timer.  Since the machine runs flawlessly for the last few years I am wondering how the MAM command works with regards as to what I will imagine is like a buffering characteristic.    ******If the program is in fact making a small MAM move then, without confirming it is complete, making another MAM on the same axis before the first motion actually completed what would it naturally do?  I'm guessing by the way the machine runs ok, it just buffers the second command because it is busy with the first.  I am surprised it does not interrupt the first move and issue an axis error or at least stop that first motion.  What would you expect it to do based on how MAM works? 

I have been through this problem before and don't recall the solution.  I have experienced this when replacing an E1101 with another E1101 about 5 years ago.  I had downloaded the project and when I hook it up to the A series CPU with 25 pin cable, most of the items on the screen are the wrong state compared to what the machine is actually doing.  There are many Digital Text objects setup to monitor an input from the PLC to show the state of all of the sensors.  I believe it was only on direct I/O tags.  Text object is set so Red is off and green is on.  Everything that should be red was green and green was red.  I did not have to redo any of the objects.  I don't THINK I had to do any firmware changes.  My Mits. dealer or the factory guided me on what to do and it was relatively simple but cannot remember.  They said at some point in the history of either the PLC or HMI hardware there was a change and they knew what to do to fix it.  I have emails/calls into some of my past contacts but am not hearing back from them yet and don't know if they will remember either unless this is pretty common with the older equipment. Actually today I am doing this with an Exter T100 file that the factory converted for me from .mpa to .cpa but the results are the same.  As soon as we plugged it in I knew what was going on but it has been too long to remember what to do to fix it.  I guess if it was more difficult it would have stuck with me or taken notes somewhere.  Any experience with this?  I'm stuck for now!  

I tried to use the verify feature to compare the project I have open to the one in the PLC.  It reports back that the parameters and main program are identical but the SFC is not identical.  What is frustrating is that the SFC comparison will not allow you to click on the SHOW button. My question is if any version of IEC developer was ever capable of this or if it is impossible since the Verify function always shows differences in the editor in IL format. I am the person that was in the PLC last and should have the latest offline copy of the program but I cannot get it to say it matches and am worried what difference there could be since I cannot dig any deeper. Did I miss anything or am I out of luck?  

I am in the US but my equipment came from a European plant of ours that shut down. It is one of our newer pieces of equipment even though you noticed it's age so it won't get any money thrown into upgrades unless it totally fails. That's partially why I was afraid of ordering a spare CPU for the machine because I was a little worried about the relative age between what I have and buying something old NIB or even on the used market.

Inntele, Thank you for the help. Once I got an answer about if there was more than one version of hardware to order I was thinking ahead about any other surprises I could find. I just went through a project last month with Allen Bradley and had not done anything with them for a few years. I was amazed at how many different firmware versions all of the software and hardware was in and how I had to upgrade my software twice and re-flash the HMI to get everything compatible between PLC, HMI and laptop. Thank you for letting me know how Mitsubishi does their hardware.

I have a machine with a Q01CPU and want to order one online as a backup from a surplus vendor. I've looked through a couple of owners manuals and seen an example of the sticker on the side of the CPU. The model number is just Q01CPU and a serial number. No detailed order or part number I can find. Is this as simple as it is? One Q01CPU is same as another except for possibly firmware revisions? What do I need to consider before buying one as an exact backup? Are firmware revisions done through GX IEC developer or another utility? ThankS!

Thanks for the quick response. I plan to use that feedback in a comparison during the move to issue a stop command also being aware of my position if needed.

I have not found an example here. I read through the manual that shows all of the variables to read/write. At least three of them sounded related to what I want but not sure if any are correct. I am going to do simple position/velocity moves to different angles. The knob I am turning will be directly coupled to the motor shaft since only hand torque is required to move it. Compact logic with kinetix 350. One of the final moves is to a detented position that I want to attempt to "feel" by reading the torque. How do I monitor the torque and stop when I reach a detentented position that requires a lot more torque to go past? I know I have heard of people doing something like this to press a bearing or a seal in but maybe that was not in position/velocity mode... Ideas or examples?

I have done what is shown in post #7 and it is working. At least at my desk spare PLC. I suspect the machine PLC will behave the same. The only thing I can add to this example of a "strange" situation is that one of my copies became corrupted when it was open and I went back to the copy on my server. It was originally written in 5.0 and had been working with it in the last couple of years in 7.03. I don't think that it was the original cause but may have added to it since this is an unusual example. I first split into two networks, one Set and one RST. Then the RST network faulted. When I combined the AND gates all together it finally ran. Thank you all for your help! I would still be scratching my head since I didn't add anything that was incorrect and it all worked before that. I'll expect more trouble like this in the future and just use the PLC Diagnostics window to pinpoint the network and try and change things until it works. Very strange...

Starting with Bryll's last network suggestion and the advice from others that follow I was putting that together with Bryll's earlier explanation of what error 6612 was referencing about number of LD commands, etc. and was figuring that redoing the network as he suggests would help. I just haven't found the time yet this week to do it. Thank you all for the advice and I will let you know what I end up doing. Thanks! I am also glad to see that others have had similar "strange" problems with parts of the program that were fine until you made other changes. Sometimes things just don't work out the way they are supposed to! I just can't remember any examples where this has happened to me. A lot of times when you can't find an explanation you still have done something wrong and have to find it. Have to go fix machines that are not working before I play with this upgrade again though....

I grew tired of systematically trying to eliminate my changes and simply took the complete program I created and took out the network I posted above. It RUNs! So the only thing I can think of is if that network was always in there running, and all of my changes run without that network - then maybe I messed up the Global Variable declarations somehow? And one of them conflicted with this network then? I'm going to start looking at that since I don't know what else it can be!

I decided to attach the network that contains step 2163. I am not sure why I am looking at this network because this network has been like this for 10 years! Maybe you will notice something though. I am also working on taking my changes out one by one but am not getting much help there either. I'll let you know if I find it...

After looking around on my own and right clicking on "Show Melsec Code of networks" I find myself at the same network that I was at when I used Debug>Show Step and typed in 2163. I am on a network I never changed. So is it possible that this is just telling me where the program stopped scanning when it faulted or is it trying to tell me exactly where the error is? I will keep looking at it until I get it Thanks for the details on the error interface.