Mitsubishi Q-series: IO Assignment page, when adding a new module...

Mas01

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I want to add a new ANALOGUE INPUT module into our PLC (Q68AD-G), but I'm a bit confused about something. I would've thought that the IO ASSIGNMENT page in GX Developer would match the physical layout of the modules in the PLC cabinet, but it doesn't.
The first 5 modules match up (indicated by tick), but then the next 2 modules (marked by "?") are physically not on the rack...on the rack they are EMPTY (QD60 blank covers).
I was planning to add the new module (Q68AD-G) in the location of the first EMPTY slot, i.e. in slot 0-4, remove the QD60 and insert the Q68AD-G. However, for the IO ASSIGNMENT page, would I need to change Row 5 to Type=INTELLI, Module name=Q68AD-G, Points=16points - and keep the same StartXY (0040)?
Thanks

Screenshot_20211027_112824.jpg
 
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Are you sure that hardware configuration has been downloaded to the PLC? If you click on "Read PLC Data", it should read the configuration that it actually sees on the rack. What happens when you do that?
 
Although those are intelligent modules according to the manual they are 16 point so there should be no problem, I believe it will not matter if you leave it at 32, it may be possible to change it to 16, however, not having some intelligent modules to test it I cannot assure you that it would not change the rest of the I/O I do not believe it will, just leave a gap of 16 I/O points I suggest you document the current addresses, change it then see if the rest stay as they are configured, you can always go back.
 
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Are you sure that hardware configuration has been downloaded to the PLC? If you click on "Read PLC Data", it should read the configuration that it actually sees on the rack. What happens when you do that?

When I click on "Read PLC data", I get this window.
The wording makes me uneasy about pressing 'Yes'.

Screenshot_20211027_155945.jpg
 
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Although those are intelligent modules according to the manual they are 16 point so there should be no problem, I believe it will not matter if you leave it at 32, it may be possible to change it to 16, however, not having some intelligent modules to test it I cannot assure you that it would not change the rest of the I/O I do not believe it will, just leave a gap of 16 I/O points I suggest you document the current addresses, change it then see if the rest stay as they are configured, you can always go back.

Thanks, yes, I will definitely record the current settings in case I need to go back. Good idea.

Just for info, There is a message on the screen in the picture "Assigning the IO address is not necessary as the CPU does it automatically. Leaving this setting blank will not cause an error to occur".
 
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When I click on "Read PLC data", I get this window.
The wording makes me uneasy about pressing 'Yes'.


It's just telling you it's going to overwrite what's in your offline hardware configuration with what it reads from the PLC. If you don't save the file, then whatever it writes there will not be saved. This is just to see if the hardware config you are looking at is not actually matching what's running inside the processor.
 
It's just telling you it's going to overwrite what's in your offline hardware configuration with what it reads from the PLC. If you don't save the file, then whatever it writes there will not be saved. This is just to see if the hardware config you are looking at is not actually matching what's running inside the processor.
Thanks, So are you saying that if I press 'Yes', it will compare the modules that are physically installed in the PLC cabinet, with what is currently being shown on the screen? If the two differ (and I think they will differ, as described in the first post), do you think the IO ASSIGNMENTS page will automatically get updated so that they match each other?
Thanks
 
Yes that is correct. Then you can see if the offline configuration is correct. You don't have to save the file or anything yet, it's just to see if offline matches online
 
What it will do is overwrite the configuration, but providing you do not save the file the original on disk will be as before, however, if you overwrite the file with what's in the PLC it will be the same unless you have installed the new card & powered back up.
So to re-iterate what you need to do if installing the card & uploading the PLC Parameters.
First make a backup copy of the program (save the original somewhere safe), do a verification of the original with the PLC to check it's the same, if not upload from the PLC to make sure you have what is in the PLC (good idea to take a snapshot of the memory as well (usually called main) Do this while the machine is not actually running i.e. the plant is idle.
power down. install the new card, power back up, read the PLC parameters (update the file), at this point you may need then to open the PLC parameters as you may need to configure the type of TC & it's conversion method etc. download the PLC Parameters to the PLC to ensure they are as required. if for some reason it selects 32 I/O points just change it back to 16 & ensure that all the addresses are as before (the ones you documented before doing anything).
Alternatively, change the PLC parameter file for the new card, power down the PLC, install the card & power back up (suggest in stop mode), download the new parameters & check everything is ok.
TBH I have never installed a card in a spare slot that is between existing cards, I have always left spare slots at the end (our usual practice was to have 10% spare actual I/O & 10% spare capacity the spare capacity was always at the end of the installed I/O, that way 16 or 32 count I/O could be installed without having to move addresses about.
 
@parky, thanks for the detailed reply.
The spare slots on our PLC are interspersed between the modules. It starts off with RTD and TC modules, then inputs and then output modules with gaps in between.
For info, I do not have the multicore cable for the new module, nor the A6CON4 connector which attaches to the front of the module...maybe I am getting ahead of myself if I don't have these items yet (they're on order).
Assuming all goes well, I assume I will need to then attach the cable and update the ANALOGUE code to setup and configure the type of analogue inputs to expect on each channel e.g. 4-20mA, 0-20mA etc.
 
It is possible to add the card now, providing there is no hardware fault but that seems pointless (hardware fault is set to stop the PLC if the card detects an internal fault). so in effect you could configure the card. before wiring.
I suggest you read this manual, it has a flow chart on the steps required that are recommended.

https://dl.mitsubishielectric.com/dl/fa/document/manual/plc/sh080055/sh080055t.pdf
 
Yes that is correct. Then you can see if the offline configuration is correct. You don't have to save the file or anything yet, it's just to see if offline matches online

Thanks, I clicked 'Read PLC data' then 'Yes' and I got this IO assignment (see pic). I was surprised to see that most of the columns were not filled in, however, the modules and gaps shown on this list matched exactly with the physical PLC layout.
I did not save the file.
Thanks

Screenshot_20211028_141510.jpg
 
As I suspected, the offline file you have doesn't show the current hardware configuration.



What probably happened:


Someone removed the cards shown in slot 4 and 5 in your original offline hardware config image, and downloaded this hardware config to the PLC, but didn't give you a copy.



You can still go online with the project and go online and see code and upload if it doesn't match, but this doesn't change the hardware config. So you can have the wrong hardware config in your file and not notice.



The problem would have came if you tried to download this incorrect hardware config at some point.


Anyways, yes it is normal for the "Model name" to not be filled in, you can just fill this in manually. But what you have to do now is add the new analog card to the UPLOADED hardware config, then download. Keep in mind with most of the Mitsubishi programs I have worked on, there are two ways of configuring a card:


1. Using the switch/detail setting in the menu you have open
2. In the Ladder program, move values into the Head address of the card


I would search for the Head address of some of the other cards and see if they are moving parameters in using the ladder program. Then you can configure the analog card the same way. Or use the menu in GX Developer that I just mentioned.


Good luck.
 
What worries me is that there only seems to be intelligent cards & nothing beyond that, there is definitely something wrong there no Digital I/O ?
Yep it's possible but seems wrong to me, also no actual addressing.
 

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