4096 I/O Max for 374CPU 90-30?

[Chris Elston 78]

Ok so the CPU374 has a 4096 I/O max, like 2041 inputs. I have a HUGE profibus system with tons of slaves, and it's going to be close. Is there anyway to expand the I/O support of the CPU374 without having to upgrade the PLC to RX3I system?

[Steve Bailey 118]

Is it possible to map some of your Profibus I/O to %M or %G memory? You have to be careful with outputs in %G. They are all retentive. Outputs in %M default to non-retentive, but can be declared either way.

[Chris Elston 78]

Man.....Why didn't I think of that! I didn't even try to yank on the pull down box. I see that I can use %R for profibus slaves that eat whole words at a time......thanks Steve, your a life saver.

[Steve Bailey 118]

Mapping the data into %R memory works fine, but the 90-30 doesn't support bit references from register memory (%R01001.00 or something like that) on a NO or NC contact. That's why I suggested using %G or %M memory. I've gotten into the habit of using %G memory for bits associated with HMI panels. Helps in troubleshooting to know that if I see a %G bit in the ladder logic, it has something to do with the HMI. It's easier to spot than a reserved group of %M addresses. It also reduces the likelihood that someone else will use up the addresses you set aside for the HMI.

[Chris Elston 78]

I do the exact same thing. All my HMI buttons are %G. I have a Trios Motion controller that eats up 16 words. It's like integer base, so %R will work perfect for it. I can write the whole word and it reads the whole word. That saved alot of %I and %Qs that didn't need to be bit based. I wonder why I can't map directly to %M in here, seems silly.....If I HAVE TOO...I have used BIT_SET and BIT_CLR or BIT_TEST to map over %R to a %M so I can break it down to bit level. It's a pain in the rump, but it can be done.

[Steve Bailey 118]

Interesting that they don't give you %M memory as an option. I can't think of any technical reason why it should be excluded. I wonder if it's an oversight, especially in light of the fact that they give you %G.

[Chris Elston 78]

I am using PME 5.50 sp1 build 3655 so it's pretty new. Using a Horner Profibus Master card, the screen shot I posted earlier was it. No %M availible to map....

[Smoke 0]

I thought I would drop a comment about the Horner Profibus Master card. We once to used the horner cards and most of the time they were fine. Now and then especially if the E-stop was pressed or a power outage happened we would loose status sometimes it was very hard to recover. We changed to the SST Profibus Master about 2 years ago. and we have had zero I mean zero issues since. and look all options

[Chris Elston 78]

Oh just great, you had to show me that didn't you? . Well I was wondering if the problem was the card or GE software. I guess it's related to the card eh?

[Smoke 0]

I don't know what your budget is but I would make the change if you can.

[RussB 22]

I'm not familiar with the SST module but the IC693PBM200 does work with the 90-30 IC693CPU374 but it does not support %G or %M or %R. I/Q maps only to %I or %Q respectivly, same with %AI and %AQ. There is not a good way of getting around the 2048 I/Q limit in the 90-30 family. With that many I/Q I would worry about programming memory. For the best results and performance I reccomend switching to RX3i and the IC695PBM300 Profibus Master. The RX3i will give you 32768 I/Q (that is ea.) and enough programming memory and speed so you will not need to worry about running out of either, there are many other advantages although cost is not one. As for accessing the bits in %R. A good way to do this is to use %M or %T as a temporary holding address. i.e. Move %R1 into %T(M or G)1 call logc using %T(M or G)1-16 Move %R2 into %T(M or G)1 call logc using %T(M or G)1-16 Repeat as needed. Or if you have just a few do a permanent map.

[Chris Elston 78]

Russ, Where did you get your information about your above statement? I deleted the the Horner Card, then inserted the PBM card and added one of my slaves. The Trios Motion Controller. When I double click on the addresses in the slave, PME is giving me a chance to map my profibus data to %G, %M, or %R. Are you saying this from experience? Why would PME let me map I/O if it doesn't support the hardware?

[Chris Elston 78]

I've always had the opposite luck with Horner. I haven't had any problems (knock on wood). And I have nothing but praises to say about the tech support I get from Horner. They help me fight a battle with MAC one time and we ended up finding a problem in the GSD file for their valves. I also found out yesterday that is seems that Horner is more than willing to fix this %M issues, but it seems that GE won't give Horner the information they need anymore to fix this nor the information they need to support a CPU374.....yeah I found out yesterday that the Horner Master Card and CPU374 are no can do pair....PME doesn't give you a warning about it either. So I will be returning my Horner card after all, and getting a GE Profibus Card. It's sad to know that my old GE supplier is the one who had said I wouldn't have any issues with the CPU374 and the Horner, and of course I didn't have a problem buying one because I knew they had great tech support (Horner that is)...And it's too bad to learn that GE is not sharing information with Horner anymore so they can't "patch" their master card to support %M or the CPU374.... So in the end, I'll either go with GE or look into the SST card. Because of my time frame, and depending on what RussB says, I might go with the GE card this time. I hate to support GE in the case knowning what I know about the Horner situtation, because it seems to me that's exactly what GE wants you to do..buy their product.... -

[RussB 22]

Sorry, Obviously I went to the wrong place (I should have come here). I don't know why but when I went to test it in ProficyME, I missed the drop-down to select different types. As such I have no reason to believe that it will not work. This project still appears to be borderline in size for the 90-30. How many "real" I/Q is there? What is the project, Process, Motion, Assembly? Would it be a canadate for distributed control? Again, Sorry for the confusion and thanks for setting me straight.

[Chris Elston 78]

I have 3 - 32 point input cards 3 - 32 point output cards 1 - combo analog The rest of the inputs and outputs are on profibus slaves. Their won't be that much ladder logic believe it or not. I am running nine IAI scara robots. It's an assembly machine with mostly pick and place type applications only at a high rate of speed. All the robots will be running their own programs, in the case of your distributed control, technically yes, I already am. The robots will take care of themselves, the PLC will just give them a "GO" command in ladder logic. I have three servos, but I am running a Trios Motion controller which again will have logic in the controller and takes a "GO" command from the PLC. I have vision which also takes a "trigger" command. I don't really see spending alot of time in ladder on this project. I've done bigger projects, but not with this much slave I/O. I've gotten my project big enough that I can't do online changes anymore with a 200+ ladder file, because during an online change I understand the 90-30 copies the the ladder before updating it online, and there wasn't enough room for the PLC to create a duplicate copy in the CPU, so my only choice was to do a STOP PLC, then download...so I've been pretty close to hitting the limit..... By the way, here is an attached I/O mapping I did just to help me keep my I/O straight, it might answer more questions. I think next time, for SURE, I will step up to the RX3i. Your the one who told me about it I think a couple of weeks or a month ago, remember I had six year old GE catalogs until just a month ago......I've been living in a GE shelter for three years, all I knew was 90-30. LOL...I'm still torn between GE and Allen Bradley, but I sure do LOVE the new PME software! So for now, I've got to catch up with the rest of you GE gurus. Next time, I'll be more educated to consider the RXi3 product. If I run into a road block, I might upgrade anyway. I hope not for the sake of the cost of the hardware. - m1270_IO_Listing.xls