Replacing PPC-CPU852 with WinCPU

[Andrei Blagaila 4]

Hy guys,

I am working on a series machine that runs Mitsubishi PLC. In the past it had PPC-CPU852 on it that ran a communication software. Starting from 2012 that part is no longer produced but we had a lot of them in storage. Now we are talking about changing it to Q10WCPU-W1-CFE. The custom software will run on it because i already checked. Because i'm not very experienced with Mitsubishi I wanted to ask if I replace the old PPC and it's HDD with the new WinCPU, should I expect any problems if the custom software I need to run on it works? In the PLC Parameter->I/O Assignment I still have the PPC written and it's HDD but at type I have empty. I used this software to run on a rack with WinCPU but not on the whole machine. Just on the rack. Do I need to change the I/O Assignment or will it not affect anything?

[kaare_t 155]

In the picture you've posted there are:

1.  (Slot No0) - Q50UDEH CPU -> OK
2. (Slot No1) - PPC-CPU852 -> OK
3. (Slot No2) - PPC-CPU852 -> Reads as "Empty" but the description says PPC-CPU852. What is it in "real-life"? Is it a CPU, or something else?
4. (Slot No3) - PPC-CPU852 HDD -> Is this where the physical harddrive is mounted, or is the description wrong?

Basically you'll also need to check the "Multiple CPU Setting" too. If you have two physical CPU's (Q50UDEH, PPC, Q10W or anything), you need to specify 2 in the "No. of PLC(*1)". If you have three physical CPU's then you specify 3 and so on. In the "I/O Assignment" it will automatically fill in the correct CPU count when you correctly fill in the "Mutltiple CPU Setting" parameters.

Regarding the replacement, I haven't worked enough with the PC CPU's, so I really don't know if replacing them will work or not. I can also add that the PC CPU's are not very commonly used so it will be a bit hard to get experienced feedback on these kinds of questions.

I would really recommend you to get in contact with your local Mitsubishi dealer, which in turn have direct contact with the Mitsubishi European head quarter. That way you can get more precise answers regarding these. But that is just my personal opinion, don't be afraid to ask questions about it, just don't expect "too much".

[Andrei Blagaila 4]

Thank you for your answer @kaare_t

So 3rd slot reads empty because the PPC and WinCPU have a width of 2 slots. Is simply bigger but it connects to the rack via one connector.

The 4th slot reads HDD because there is a hard drive mounted on that slot to back up the PPC. The multiple CPU's setting has already been done. I just want to switch the old PPC with the WinCPU. 

I loaded the software to the PLC CPU and have done the modification on my test rack (I don't have the luxury of having the machine here to try it out on it and I want to inform myself about possible issues I may have on the field. No errors occured and the WinCPU runs as well as the Q50UDEHCPU. 

I contacted my Mitsubishi Rep but here in Romania he informed me that they have not sold a single WinCPU or PPC from his knowledge. (I received mine straight from Japan).

My follow up question is, if i leave the I/O assignment the same and just put empty where the HDD was (WinCPU has CF Card for back-up) will it affect my program? 

[kaare_t 155]

No problem!

If you leave the slots as "Empty" both in the IO Assignment and in "real-life" then you won't have a problem. So basically; put your IO cards exactly where they where before you changed the PPC.

Also: In your IO Assignment picture, you have explicitly specified the IO start addresses which means that it's pretty straight-forward to check for possible errors. You can see that the first empty slot reads start IO 0010 and with 16 points occupied the next one of course reads start IO 0020 and so on. Just follow the IO Assignment settings on your physical system then you should(!) be good to go.

By the way, just out of curiosity: What is this machine you're working on doing? You've posted a lot of topics regarding Mitsubishi PLC/PPC+++ and I'm starting to wonder what kind of machine this is (what is it doing...)? No need to answer if it's a "secret", I'm just curious...

[Andrei Blagaila 4]

It's a machine in the semi conductor industry. The ppc/wincpu is used to run a custom c written software that communicates to a host through the SEMI standards. It basically takes the state of the PLC variables via the rack bus and sends them down to the host.

I'm curious. If I leave the I/O assignment as it is and just change the PPC with the WinCPU should I expect problems? The points allocated to the HDD are just not used in this care right?

[kaare_t 155]

That is correct. When it says empty, it is not used. When it says 16 points, and empty you can think of it as "reserved" area. Basically you can use it in the future if there is physically free space in the slot.