Hi, we have been working with 10 qty CPU 1518TF-4 PN/DP,

on one PLC, we get the following: (see extract from PLC diag buffer attached)

Event ID: 16# 02:4175

We have swapped SD cards between a working CPU and the suspect CPU and after also swapping card contents, the fault stays with the CPU, suggesting an error with the actual SD card hardware.

My question is can there be anything HWConfig/software-wise that may cause this symptom or are we simply looking at a warranty type issue?

Regards,

Graeme

Hi!

For your case, I have found some posts that may help you with your problem.

https://support.industry.siemens.com/forum/ww/en/posts/memory-card-error/62959/?page=0&pageSize=10

I think you should also check the following FAQ:

- How do you detect an inconsistently or incorrectly formatted SIMATIC Memory Card (SMC) and how do you repair it?

https://support.industry.siemens.com/cs/ww/en/view/69063974

Br!

Before inserting another memory card into the plc slot, shine a bright light into the slot and examine the pins that make contact with the card's contact pads.  See if one of them is bent and touching a neighboring pin.

Sometimes this happens with PN port pins, sometimes it happens with other types of devices where a minor thing happens during manufacturing that causes the springy pin to stick and not spring back.  Not to single out Siemens as I've seen this type of problem on multiple manufacturers over the years.

Also, not suggesting it is likely, only that it is possible to diagnose on-site, use precision dental instruments or other small curved pointy instruments to convince the bent pin(s) back into proper position.

If the RMA can get you a PLC replacement within 24 hours, go that route and get a refurbished (or new) unit from Siemens under warranty.  If it is no longer under warranty, definitely carefully try this approach.  Get your most steady handed and patient technical person to perform the pin surgery as it is easy to make things worse.  If you can get a picture of the "as is" of the existing pins to guarantee Siemens warranty coverage, that is preferable - assuming there is pin damage.

Graeme

Hi, we have been working with 10 qty CPU 1518TF-4 PN/DP,

on one PLC, we get the following: (see extract from PLC diag buffer attached)

Event ID: 16# 02:4175

CPU error: Memory card evaluation error: Inconsistent external load memory structure

current card type: Program card (external load memory)

Function finished/aborted, new startup inhibit set: ..

- External load memory is corrupt

We have swapped SD cards between a working CPU and the suspect CPU and after also swapping card contents, the fault stays with the CPU, suggesting an error with the actual SD card hardware.

My question is can there be anything HWConfig/software-wise that may cause this symptom or are we simply looking at a warranty type issue?

Regards,

Graeme

Hi all, just a quick update ...

This has now happened on several separate PLC's and appears to manifest during (or just after) a download.

At the time of the fault, moving the suspect SD card from the defective PLC to another PLC works fine, so it can't really be the card.

The "fault" definitely stays with the CPU (but does not appear to be hardware related).

Once the suspect SD card is reformatted in the CPU slot, it appears to work fine for a period of time/number of downloads, so unfortunately, we will have to see what other patterns emerge and update when we have more (or even better a solution)

Regards,

Graeme

Hi,

I had the same problem with a CPU 1517T-3 PN/DP (and also with the "TF" version of this CPU).

I solved the problem of this random FAULT (which happens most of the times after a download) just by upgrading the CPU to the latest firmware available.

I upgraded to V2.9.4 and since then the problem disappeared.

(I can see that at the moment you are using V 2.9.2 and I think it isn't the last one for CPU 1518)

Hi Davide, thanks for the input.

It's one of the first things we did after it happened a few times. We were hopeful that the firmware upgrade would solve it when we saw that the failures seemed to occur on older firmware initially.

All our CPUs have now been upgraded to the latest firmware as attached. It has however, occurred on CPUs with the latest firmware regardless (as well as on CPUs with the latest hardware build revision)

Regards,

Graeme