Omron C200H and possibly IO table issues

Dear all - hope you can help and this is an easy fix to a standard newbie issue. I feel very much at home on Telemechanique PL7 but quite new to Omron and CX Programmer (Ver. 5.00).

Recently I was called to take a look at a PLC system with 'mem error' after blackout - actually 2 inter-connected C200H racks. Figured program was lost. Even with Error I could hook up to PLC and download a backup copy of the PLC program - CX Programmer did say 'Fatal Memory Error'. In the corner of the Error Message dialog there was a 'Clear All' button - which after some hesitation was clicked. Attached warning came up 'PLC will initialize all areas. Including PLC Area, Parameter Area and IOM Area' beleaving all date was secured in my download I crossed fingers and hit OK..... however, same result with Memory error.

After studying status bits I realized the system DIP switches had been mis-aligned. The C200H had a memory card installed. DIP1 was ON and enables 'Memory Protection' and DIP2 was also ON enabling 'Read from Card during Boot' - main problem then would be for PLC to read program from memory card and put it into the protected PLC memory. Once I removed/ turned DIP1 off and power cycled the PLC, then system reported no error and could be put back into RUN. All looked good....but I ran into problems when operating the Analog modules. More exactly the Analog Output (C200H-DA002 Analog Output).

I went through the electrical diagrams and controls - all good. Started to reverse engineer the quite large PLC logic and found Output being forced to 0.. so this would be why we did not get a signal out. On this system they were un-sure of the parameter list which came with the system. Some values were hexadecimal, some decimal and they had questions on how to convert curve data and other setpoints to something PLC would understand.

Back home now planning next visit to fix issue - I believe the questions on the parameters are cleared up, but result remains the same. No analog output.

Today I started thinking back on the 'Clear Memory Warning' 1.) Program Area: was re-installed from memory card
2.) Parameter Area: was re-entered from handheld console
3.) IOM Area: has NOT been re-loaded... think this could be my problem unless PLC can re-create the IO area itself?

Attached is a screendump of the IO Table downloaded - and it looks very 'generic'. The actual setup is:

C200H-OD215 (DC Output Unit 32bit), ID0
C200H-ID212 (DC Input Unit 16bit), ID1
C200H-ID215 (DC Input Unit 32bit), ID1
C200H-AD002 (Analog input unit) 4 signals in, ID2
C200H-DA002 (Analog output unit) 4 signals out, ID3
C200H-DA002 (Analog output unit) 3 signals out/1 spare, ID4

The 2 digital input units share same ID - attached is also a photo of the PLC rack, so question is... would/ could this be the cause of my trouble? Does this behavior correspond with your experience? I could imagine the forced output of zero is because this is fail-safe state or a reading out of range.

All digital signals seem to be good, so I am not sure issue is missing IO Memory area. And if it is - it could seem I will have a hard time defining actual IO table/ hardware with CX Programmer 5.00... but what did they do 'back then' in 1995 when something like this happened.

Any suggestions/ or testing ideas in how to move on with this issue is greatly appreciated. Want to make a list of tests since job site is offshore without internet connection. The backup file with the ladder can be forwarded upon request.

Sincerely,
JP

this may or may not be of use to you, i had a problem with an omron cqm after a power out and the plc battery was in poor condition, the plc went into outputs inhibited mode because of these conditions (including analogue) , after replacing the battery the problem was still there, basically. after the initial fault conditions occurred a bit was turned on. SR2????. to turn it off i had to reload the program with an extra line of code to turn off this bit which i found in the manual.
again, possibly not related, but maybe something to look at.

Thanks Pmac10 - appriciate the promtp feedback. I am aware my description is a 'bit' long and can be discouraging. So very happy how fast you came back to me on this one. I will check the SR bits, but pretty sure they are clear now. Also quite certain the DO were OK... just the Analog Outputs are messing me up.

Had the something like the same problem with a MAD01 analog card. Whiped memory and poof card wont work anymore.Gtsuport helped me by saying to set the memory areas DM for that card, as shown in the manual. You need manual W229 if i remember correctly. Hope that helps

If you go to the I/O table tab and click on the card concerned then upload from PLC you will probably find the card is in default mode ie no outputs turned on. You will probably find the same with the analogue input cards too. These settings are not saved to a memory card at all. You can write the settings in ladder if you wish or just setup from the I/O table. There must also be a doubt as to whether the latest program has been saved to the memory card - if it is an EPROM probably not - if an EEPROM maybe.

Thanks Patrix - I did go through the manual for the Analog Cards and following is verified:

DM1200 holds info for which channels are enabled AND if I need BCD datatype instead of HEX.

DM1201 holds info saying all my signals are 4-20mA.

DM1202 holds info 'scale' is active.

DM1204 holds INP1 scale low value is 0
DM1205 holds INP1 scale high value is 4095

Etc. for IN2, INP3...

Nothing to be configured on the OUTPUT as far I can see.

So these settings should be good - but thanks a lot for the pointer

BobB said:

If you go to the I/O table tab and click on the card concerned then upload from PLC you will probably find the card is in default mode ie no outputs turned on. You will probably find the same with the analogue input cards too. These settings are not saved to a memory card at all. You can write the settings in ladder if you wish or just setup from the I/O table. There must also be a doubt as to whether the latest program has been saved to the memory card - if it is an EPROM probably not - if an EEPROM maybe.

Click to expand...

BobB aka OldPhart

This sounds interesting - if this is the default behavior after a Memory Clear I bet this is what is going on. I would not know how to set this up in ladder, but I for sure will try to enable them with my CX Programmer ver. 5.00 and upload to PLC. This has to be done while online, right? Asking since offline does not give me 'SIOU Setup' as an option (greyed out).

If you saw my earlier JPG upload of the IO table I downloaded from PLC (before my Mem Clear), you will see it does not look like the actual hardware rack (also as a JPG). Almost all modules are Analog IO. I guess unlike AIO then DIO does not care too much about being enabled? I would like to make a complete match if the IO Table and the PLC IO Memory -> Verify OK.

As for the version on the EPROM I think we are OK but thanks for the heads-up. Travel is Wednesday and hope to be back before the weekend.

I know there are tree ways to setup a card. 1 is you use the i/o table. Never done that before, our i/o tables are blank. 2 use the move instruction to set the right bits of the data memory (convert binari to hex). 3 set the right bits in memory area directly.

Patrix said:

I know there are tree ways to setup a card. 1 is you use the i/o table. Never done that before, our i/o tables are blank. 2 use the move instruction to set the right bits of the data memory (convert binari to hex). 3 set the right bits in memory area directly.

Click to expand...

Thanks - I guess I am doing all of it.. setting bits within the DM and want to config via IO table - lets see who wins.