Using the same S7-317 2PN/DP with two different software

Hi all,

I have a 317 2PN/DP CPU with some I/O cards in a rack which I'm using for a part of my plant.

It has been programmed in Step 7 about 8-9 years ago.

I would like to upgrade the software but I don't have a long available downtime so I think I have two solutions in front of me.

1) Migrate to a S7-1500 (meaning buying load of hardware now, with a perfectly working CPU)

2) Using the same CPU with a different software during commissioning time (reusing the old software on night shift in example).

I'm not totally sure, but is it possible to buy a second MMC card, and use it for the tests and then, at the end of the day, switch off the PLC and reinstall the original MMC to have the old software?

I might have a slightly different hardware config, different IPs etc, that's why I was thinking to simplify the swap buying a second MMC, rather than downloading software days and nights (risking to lose DB data etc).

Moreover I think I can program the same CPU with TIA portal in the new MMC, having an upgraded software version I could use when I decide to buy the new S7-1500 CPU & configuration.

Could this work?

Any other suggestion?

Good morning Daniel,

Thank you for your kind reply.

For this project I don't need to re-work the existing software but I was planning to start from scratch a new one with TIA v16.

Rethinking a bit the whole process, maybe worth to stage the migration in few steps.

At first stage the HW configuration would be the same, I would only change IP addresses since we want to add the system to our main network SCADA and we can test the existing hardware.

Can you confirm me that the Hardware Configuration is sitting on the MMC and swapping from one to another I'll have the new addresses set correctly and not changing any slave configuration I shouldn't have hardware errors?

I can then plan to add ET200S slaves or I/O cards at the next stage, once we are happy with the new software.

Thank you.

Hello,

The hardware configuration is on MMC (It is inside SDB's)

Best regards,

Wizard

thank you! I thought it was like that but I'm a bit rusty with these things :)

One last thing, hopefully.

How can I choose the right "spare" MMC.

At the moment there is a 2MB card installed and memory used it's about 15%.

Obviously it will depend on how I program my new system but, let's say it would be similar, should I need more space programming with TIA portal?

Thank you again for the great help!

Hello,

Choice of the amount of Load memory (MMC) depends on the Work memory of used CPU.

The Load memory should be 1.5 times the Work memory (In that case you can use the complete workmemory)

Best regards,

Wizard