SLC 5/03 SCP instruction problem

Asefakaratas

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Join Date
Jan 2019
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Istanbul
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Hello everyone,

I am using SLC 5/03 (1747-L531) CPU. My CPU gives an error. BATT led is active and it is always in solid red . Firstly I changed the battery and I can download an empty project the plc. I made VCC and GND terminals 90 seconds in short circuit position. But the problem persists. Picture is in the attachment.

Then I decided to replace the CPU. I will use the 1747-L532 CPU. But when I replaced the controller in the my project, when I use 1747-L532, My project gives errors. I guess SCP function doesn't support in the 1747-L532.

What would you suggest for the solution? Thanks to everyone in advance.

slc_batt.JPG
 
It maybe your power supply that is the issue and not the L531

What is the date on both the L531 and the L532? maybe the L532 is a older firmware, the only difference is memory size (8, 16 and 32) unless the firmware is older
 
You said it gives you errors. What are those errors? Also you did not say if swapping controllers eliminated the battery issue. I am assuming it did.

You can upgrade the firmware on the L532. It requires a firmware upgrade module that you plug into the UVPROM socket. Not sure if you can still purchase it, but I would reach out to my AB distributor and see if they have one that you can borrow. Or possibly you can bring in your controller and have the upgrade done at their facility. When I worked for AB I used to do this from time to time. The upgrade module supports all models of the 5/03.

If your 5/03 doesn't support the SCP then it is one of the very first 5/03 controllers. The firmware upgrade I think coincided with the release of the 5/04 which had this firmware update included from the start.

Have you tried swapping the battery from the 532 to the 531? You know that battery is good when it is installed in the 532. Do you still get a battery fault with this good battery when you put it into the 531? If so, then you know it is an issue with the 531. Not sure that is repairable.

OG
 
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Thanks for your answers guys.

When I tried different a power supply, the problem persists. Date of L531 is older than L532. The L532 CPU's date looks 2019. The L531 has been running for 10 years. Probably I think CPU is broken.

The errors I mentioned are not in the form of error code. Only the batt led lights solid red and consequently does not operate other modules. I tried with the battery of the L532 CPU. Nothing has changed.
 
Edit : I saw that the CPU I used was 1747-L532C / D series and the problem was fixed. When I changed and checked the controllor in the RSLogix500 software, I saw that there was no problem. It is worth saying. In such cases, it is necessary to update as "Operaghost" says. Otherwise, you cannot directly convert some instruction blocks.
 
Operaghost said:
...If your 5/03 doesn't support the SCP then it is one of the very first 5/03 controllers. The firmware upgrade I think coincided with the release of the 5/04 which had this firmware update included from the start...

Close, but not quite...

The first SLC 5/04 hardware release was the "oddball" Series A 1747-L542 24K model (Aug 1994). It was released with the initial OS400, Series A, FRN 1. This was further updated as far as OS400, Series A, FRN 4, but SCP instruction support was never added for OS400 as it was not yet introduced to any SLC processors.

The next SLC 5/04 hardware release (Dec 1995) was the Series A 1747-L541 16K model and the upgrade to the 24K model, the Series B 1747-L542, which was now a 32K processor. That had given the 1747-L542 Series A 24K little more than a year to establish itself in the automation world. These newer models were released with OS401, Series A, FRN 5. It was this OS401 initial release that introduced support for the SCP instruction, among others like CPT, SWP, and a host of trigonometry and exponential math instructions (SIN, COS, TAN...).

The L542 24K, having been quickly superseded, pretty much died away as an option as the 16K and 32K models became the goto SLC 5/04 processors that users were selecting. Why choose a 1747-L542 Series A 24K when the latest 1747-L542 Series B is a 32K?

So, we could say that the "real" SLC 5/04 models were indeed initially released with support for the SCP instruction, but technically the "oddball" 24K was released first without this support. If it did little else in its brief marketing lifetime, it still owns this accolade...as the first.

Still, I have no doubt, and would not be surprised to know that there are most likely a number of 1747-L542 24K processors still out there doing their "who needs SCP" type thing?

Regards,
George
 
I am glad you got sorted out.

I just want to mention this to you...

Asefakaratas said:
...Only the batt led lights solid red and consequently does not operate other modules. I tried with the battery of the L532 CPU. Nothing has changed.

The battery LED indicator being on solid RED does not prevent the processor or other modules from functioning properly. It just means that if the processor is powered OFF long enough for the capacitor to drain, the program will be cleared from memory because there is no battery backup available. In other words, as long as the processor is powered ON, the status of the battery is somewhat irrelevant. The root cause here was something other than the failed battery. As you mention above, replacing the battery did not resolve the issue you appeared to have. It was most likely a hardware issue with the original processor.

The other issue (SCP error) with the replacement processor was of course due to the fact that you had selected too old a Series model from the "Processor Type" list, which did not yet support this instruction. Support for the SCP instruction was added at OS302, Series A, FRN 9. That is Operating System 302, OS Series A, and Firmware Release Number 9. Not to mix the Series of the OS up with the Series of the hardware.

And yes, just because you have selected a processor type in the software that compiles the original project successfully for you, it does not mean it will actually work when downloaded to the controller. You must make sure that the actual processor firmware (FRN) is flashed to a supported revision.

Regards,
George
 
I am glad you got sorted out.

I just want to mention this to you...



The battery LED indicator being on solid RED does not prevent the processor or other modules from functioning properly. It just means that if the processor is powered OFF long enough for the capacitor to drain, the program will be cleared from memory because there is no battery backup available. In other words, as long as the processor is powered ON, the status of the battery is somewhat irrelevant. The root cause here was something other than the failed battery. As you mention above, replacing the battery did not resolve the issue you appeared to have. It was most likely a hardware issue with the original processor.

The other issue (SCP error) with the replacement processor was of course due to the fact that you had selected too old a Series model from the "Processor Type" list, which did not yet support this instruction. Support for the SCP instruction was added at OS302, Series A, FRN 9. That is Operating System 302, OS Series A, and Firmware Release Number 9. Not to mix the Series of the OS up with the Series of the hardware.

And yes, just because you have selected a processor type in the software that compiles the original project successfully for you, it does not mean it will actually work when downloaded to the controller. You must make sure that the actual processor firmware (FRN) is flashed to a supported revision.

Regards,
George


Thanks your answer.

Yes, as you said, it looks like a hardware problem. I did not get any errors in the software when I changed the CPU with 1747-L532C/D. Are you saying that I may have a problem due to overhaul? Did I understand correctly? Because I haven't fully tested its operation yet.
 
You're right George. I was thinking of the 5/05 that had this baked in from the start. For the 5/03 it wasn't until OS302 and, as you mentioned, the 5/04 was OS401.

Long time since I had to think about those!

OG
 
Asefakaratas said:
Thanks your answer.

Yes, as you said, it looks like a hardware problem. I did not get any errors in the software when I changed the CPU with 1747-L532C/D. Are you saying that I may have a problem due to overhaul? Did I understand correctly? Because I haven't fully tested its operation yet.

You've selected a Series C/D model and that has satisfied your project's needs, as in it will compile in RSLogix 500. But have you downloaded this program and placed the processor into RUN Mode and it is operating properly (or as best you can tell)?

If OK, then you should have nothing more to worry about.

If not OK (best explain any further issues here) then it is possible that the downloaded program, with SCP logic added, will not run properly on the replacement controller because the firmware in the controller is not at a new enough firmware revision (FRN). As we have been alludeing to, you must be running at minimum OS302, Series A, FRN 9, or newer to support the SCP logic that the original program included.

That is the only issue I was pointing out that could still be a stumbling block here, "if" you have not yet tested the converted program in the actual processor.

Regards,
George
 
You've selected a Series C/D model and that has satisfied your project's needs, as in it will compile in RSLogix 500. But have you downloaded this program and placed the processor into RUN Mode and it is operating properly (or as best you can tell)?

If OK, then you should have nothing more to worry about.

If not OK (best explain any further issues here) then it is possible that the downloaded program, with SCP logic added, will not run properly on the replacement controller because the firmware in the controller is not at a new enough firmware revision (FRN). As we have been alludeing to, you must be running at minimum OS302, Series A, FRN 9, or newer to support the SCP logic that the original program included.

That is the only issue I was pointing out that could still be a stumbling block here, "if" you have not yet tested the converted program in the actual processor.

Regards,
George

I tested the new CPU. There is no problem in the led states of the CPU. But Some modules seem to have malfunctions, some modules don't What could be the reason for you? I am not connected yet through the software. But there is no error condition in the CPU. When I measure power, 218V
 
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