C28K Omron memory error

Hi does anyone know how to clear this error message on the C28K Omron, it say memory error and it will not let me clear it the normal way. I checked all possible causes that might make this error go on, and I cannot find anything wrong with it. Could the processor be damaged or is there something else I can do?

http://www.omronkft.hu/nostree/pdfs/plc/cxxk/w146e15_c20k_c28k_c40k_c60k_operation_manual.pdf

Check Memory Unit to make sure it is mounted and backed up properly. (This is for the EPROM) Perform a Program Check Operation to locate cause of error. If error not correctable, try inputting program again.

If using a handheld programmer. Switch to program mode. Hit CLR MON CLR to get to clear the error.

Hope this helps you out.
Regards,

I am having the same exact issue on a C40K. I have the PRO15 programming module. I can clear the error, however, when I put it back into run mode the error returns. I have taken the cover (that has a board on back of it) and put it into another C40K that I have running a different elevator. The error follows the cover.

Here's my question. Is the programming stored on the board on the backside of the cover or the board that is in the base of C40K (the board with the battery and relays on it)

http://omronkft.hu/nostree/pdfs/plc/cxxk/w147e31_c20k_c28k_c40k_c60k_installation_guide.pdf

The above is the installation guide for these units. The program is stored in RAM on the top board. This is why you only have approximately 5 minutes when replacing the battery on the unit.

If you are running RAM only and not EPROM then change the first code to the END(01) statement in program mode. (Remember the code that you over wrote.) Run the program to see if the error will clear. If it does then the error is in the program. If not then the error is hardware related.

Regards,

Gary, thank you for the quick reply. Forgive my ignorance but I couldn't find it in the manual. Is the "TOP BOARD" the one that is mounted in the base (with the relays and battery on it) or is it the one in the cover?

I am running RAM only. Can I change the first code to END(01) as you suggested with the PRO15 programming console??

This type of error occurs on older Omron units S6 - unit i'm familiar with.
the internal battery needs to be charged.

power up the unit and let it sit for a day or 2, I know you don't like that part.
power down the unit and wait 10 seconds.
power up the unit, and see if the error clears, sorry but I cannot remember how to clear the error using the programming terminal.

regards,
james

Thanks for your help gclhortt. I found an instruction in the program with no data on it. That's what gave me the error.

Hi Sam
The top board is the cover. This is what is separated after you remove the four screws.
You can change the program with the Pro15.
Switch to program mode. - Slider
CLR Mon CLR
Arrow down
You should now see the first address 0000 of the program.
Make a note of the instruction. Example: LD 1
Press FUN 01
Press Write
Switch back to run mode.
If the error went away then the program needs to be checked. If the error persists then you have a hardware problem.

Let me know how you make out.
Regards,

Thank you very much Gary. I will try this very first thing in the morning and let you know what I found.

This error began when I removed the cover, changed the battery, and put the cover back on if that offers any insight what the problem might be.

Sam

Gary,

Thank you for the advice you gave me yesterday.

I changed the first line of the program as you suggested. The error did in fact go away.

Program issue then?? The company who wrote the program is long gone out of business. How would I check the program??

How do I change the first line back to what it was??

Thank you,
Sam

Hi Sam,

On the Omron 'K' series PLC's you have 5 minutes to change the battery. The 5 minutes includes removing the power, unscrewing the 4 screws, unplugging the battery, plugging the new battery in.
It sounds like the program, or part of it has been lost.

To change the fist line back on the Pro15.
Switch to program mode.
CLR Mon CLR
Arrow down
You should see the End(01) function on this line.
Enter the code that you noted above. Example LD 1
Hit LD key and then the number key 1
Hit write
Place the switch back into run mode.

In order to check the program, you will need a copy or printout of the original program. Do you have anything available to you?

The memory error will occur when parts of the memory have been removed. I would first check to see if a program is in the unit. On the Pro15 do the following:
The Switch can be in any mode; Run, Mon or Program.
CLR Mon CLR
Use the down arrow. This will scroll through the program. At the end of the program you should have an END instruction.
This will be good to compare to the original program.

The instructions for the Pro15 are in the operation manual. Here is the link.
http://www.omronkft.hu/nostree/pdfs/plc/cxxk/w146e15_c20k_c28k_c40k_c60k_operation_manual.pdf
If you go to 4-6-5 Program Searches you can search for the END instruction.
Any mode.
CLR FUN 01 SRCH - This will search for the end statement
Hitting SRCH again will continue the search.

Regards,

Thank you again.

This was the 6th battery I changed that day. If I took longer than a minute and half it was a long time.

I have nothing available to me as to the original program except what I can what I see on the PRO15 against the other identically programmed units I have on property (about 15 of them).

I am going to take some time to study the manual and complete the other checks you suggested.

I will keep you posted.

Thank you,
Sam

Gary,

SUCCESS!!! I can not thank you enough for you help.

As I was scrolling through just over 1000 lines of programming to find the END instruction as you suggested I noticed that line #861 was "????". I thought, gee that might be a problem. So I walked over to another elevator that is identically programmed and looked at line #861, rewrote that line on the down unit accordingly and BOOM...the elevator took off running.

THANK YOU THANK YOU THANK YOU!!

Best regards,
Sam

Hi Sam,
I'm glad that you got this going again.
Have a great day.

Hi Sam,
Since the Omron 'K' series of controllers are no longer made or supported, I was thinking about your situation and two things came to mind. Documentation and Backup.
Documentation:
I would write down or document the program that you have in the controller.
Backup:
I would look to have another PLC programmed and ready to install if the PLC fails again. Remember that the MTBF (mean time before failure) is with the power supply of this unit.
In my plant we still have some 'K' series PLC's. I have converted the programs over to a Click PLC from Automation Direct. The reasons were free software and inexpensive hardware. (< $500)

If you have any questions or need further information, please contact me.
Regards,