Time update issue with Omron CJ1M-CPU11-ETN

I've been thrown to the wolves on a project that was done long before I started. A customer put in a Omron set up and is having trouble syncing the plc clock with the server clock. They are using a CJ1M-CPU11-ETN. Our Omron rep went to the site and changed the settings, but they didn't hold. I'm not experianced with Omron controllers (yet) so I don't know what to look for. I'm just looking for ideas here. I haven't been to the jobsite yet and they haven't gotten me a program to look at. This just came up in the last few days, before I went out of town. Any help or direction is appreciated.

I am not sure I can be much help on this but, you should get a copy of the Instruction Reference Manual #W340. This thing is huge, over 1100 pages. You can download it from www.knowledge.omron.com. Just search for W340. There is an instruction DATE(735) that will change the internal clock settings to the values specified in the instruction. What I am not sure of is how to read the server clock value to put it into the instruction.

Guessing that others on the forum should be able to point you in the right direction.

You need to go PLC>Edit>Clock and set it as your PC.

It work fine for me.

That was done before and it didn't stick. I guess I should be a little more specific. The daylight savings time change did not occur. When it was changed on the plc to fix it, the time went back to the old after about 3 weeks.

Sounds like there could be something else writing to it. Have a look at the manual has gtsupport suggests, and then check the code for to see if it is being updated by something else.

When it was changed on the plc to fix it, the time went back to the old after about 3 weeks.

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Sounds like there could be something else writing to it.

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Definately agree that probably something else is writing to it.

Is there a SCADA or some other type of comms program to the PLC that could be re-writing the time clock? Sounds very much like it. If there is a SCADA, there may be an ActiveX component writing to the time clock. That is becoming fairly common. If the PC has not been set up for daylight saving time and the ActiveX component is set up to write the time at regular intervals to the PLC, that would probably explain the re-writing of the time clock.

Well, I hate to relive the past, but I'm back to the same problem again. I went to the jobsite the other day and changed the times using the trusty PLC-edit-clock method. It resynced the time and everyone was happy. That was at 11:00 in the morning. at around 2:30, all the PLCs I had changed were an hour ahaed. This problem started at the daylight savings time change in Oct. In the program, I cannot find where the internal clock addresses would be written to, but I see that they are being used to movd from them to a d memory location. They are then written to a LED display, along with some other stuff. The PLCs are on a wireless network, but the server does not have the Omron software to connect to it. I used my laptop while connected to the server. It does have an OPC Server, Kepware I believe, and ICONICS is being used for reporting and some graphics. The only thing Iconics sends out is scheduling info for the line, as far as what product to run that day. Am I the only one that sees this problem? Why wouldn't the time sync hold for more than 3 - 4 hours?

This is definately not a normal problem. I have never seen it happen before unless something is writing to the time clock channels. I will do some further investigation but if I remember correctly, a bit has to be set to stop the clock, allow the changes and then restart. It suggests to me that there is an Active X, or some other container, in the PC (possibly in Iconics) that is writing to the time clock. I am thinking it may be possible to disable the clock write function if you cannot find the container but not sure. Let me have a look.

Thank you, I really appreciate that. The tech support at Omron are dumbfounded with the whole thing. If there are any more specifics I can add, let me know.

Here is a copy of the "Date" instruction that can be used in the PLC to change the date/time. There are also instruction to add/subtract to date and time but are probably irrelavant here unless they are in the program. Look for instructions like "CADD" - calendar add.

The attached pages also refer to FINS Command 0702 - it is possible that the SCADA may use this command in a container or code of some sort and change the clock. If the connection is serial you may be able to monitor the traffic to and from the SCADA to see if this command is being sent to the PLC.

I would certainly be having a good look at the SCADA for a container/code that is changing the clock and also the PLC program to see if someone has tried to program daylight saving into the program and fouled it up.

The other instructions are included in the pdf file as well.

It appears that a direct write is possible to the clock these days. That used not to be the case but it is now. Makes it impossible to stop from an external source.

Hope this helps.

Thanks, I will look into this a little further and let you know the results.