Q Series Memory Card

[JDHammond 0]

Our memory in the PLC only has 4000 bytes left. I can only do online edits because when I try to write to PLC it says the memory is to low. We purchased a 4MB flash card for the PLC. Do we clear the memory in the processor and write to the flash card? Any helpful information like installation and using the flash drive? Thanks

[Crossbow 297]

The memory card is NOT for expanding the PLC program memory, it is for backing it up. Different memory cards have different functions. What CPU are you using? What memory card did you buy? 4000 steps is still quite a bit of memory. Why do you say you only make online edits anymore? If anything, online edits would stop working before downloads. Sounds more like a configuration issue than a memory problem. Keep in mind each program you create in the Q is stored in the PLC. If you stop using a program, or download different programs with different names, the old ones are not automatically deleted. You may have some old items using up memory. To check this, in GX Developer go to Online, then Read from PLC, and see what is shown. Also, each ladder program has a default buffer of 500 steps for online edits. If you have 10 programs, then that is 5000 steps of code space lost. That number is adjustable. SH(NA)080483 and SH(NA)080484 describe the Q series system in great detail. You might want to review these 2 manuals.

[JDHammond 0]

We are running a Q61P-A2 CPU. The card we bought is Q2MEM-4MBF. We have 45 ladders (subroutines) in the program. When I go to ONLINE, Write to PLC, and at the bottom is has a button for free space volume. It only has 4096 Bytes, not steps, or does that really mean steps? Yeah in each program we have about 400 something steps remaining for online edits, that what we normally use to change the program because they wont let us shut the machine down, so we have to edit online. When we sent guys to the Mitsubishi class in GA, they said it was the biggest program they have seen on one processor. Are you saying we need to clear the processor memory and download our latest program? We do change the name when we do a change with the date. Reading more into what you said, if I have 45 ladders, I have 22,500 steps being used up just for online edits? How many steps does the Q61P-A2 have? I really appreciate the help!

[waynes 8]

This number is for a power supply. The CPU is next to this card - Q00, Q01, Q02(h), Q06H, etc. Let us know...

[JDHammond 0]

Q06HCPU

[panic mode 246]

then the card is probably Q2MEM-4MBF as already suggested ROM type of cards (Flash also ROM) cannot be used to expand CPU memory, this is used for program backup. did you check SRAM cards like Q2MEM-2MBS or Q2MEM-4MBS?

[JDHammond 0]

No, we didn't. In our training manual is sounded like that you could use the Flash ROM card or the RAM card to expand memory. ROM is read only memory and RAM is random access memory? So what is the purpose of the Q2MEM-4MBF? What's the price for a Q2MEM-4MBF?? I appreciate the help!!! Sorry bout that I meant the Q2MEM-4MBS?

[Crossbow 297]

The Q2MEM-4MBS is not for the Q06HCPU. It only works in the new iQ processors. Keep in mind too you can upgrade to a Q12HCPU (124k steps) or Q25HCPU (252k steps). Your current Q06HCPU has 60k steps. As stated before, even the RAM cards cannot expand program memory. You are limited to the 60k built into that CPU. Memory cards are for backup purposes or file register storage, not expansion of program memory. I know this is covered in the class, as I have been there too. What I said about changing program names was if you rename one of the ladder diagrams and download it, it will be in the PLC with both names. The project name when you save the program has nothing to do with the PLC. YOu if you have a ladder named MAIN and you rename it ALARMS and download, both MAIN and ALARMS will be taking up space in the PLC. Also, if you download comments or embed statements and notes, those occupy large amounts of memory. Consider removing the documentation from the PLC, and that will free up space. There is an option in GX Developer to confirm project memory size. It's in the Tools menu, and only works for Q. Check the items to be sent to the PLC and then look at the size they occupy. And asking for pricing is typically best done with your local distributor. The manuals which explain the Q Series hardware including the processors and memory cards and system design are SH(NA)080483 and SH(NA)080484 which you can download at www.meau.com. If you want to send me a copy of the program, I can certainly see where the memory is all going.

[panic mode 246]

i didn't use memory cards often but if i remember 2MB SRAM costed about 3x more than same size Flash. The only time I've seen people use memory cards for is to either make program backup or to store comments. CPU ram was the only memory that was used for program and 60k steps is a huge program. How well the program memory is used will depend on experience and programming style of the programmer.