Need to snapshot tags prior to event

Hi,
I've got an event in my process which I need to see the prior data to troubleshoot. I'm using compactlogix hardware. My plan is to continuously record 10 tags every second for 60 secs, as the new data comes in old would be overwritten, when the event occurs I would stop updating the data. I would like some ideas on how best/easily to accomplish this or other recommendations.

After the data is captured ideally I would like to view in graphical format. Can I get this data to excel, etc.?

Thanks,
Jim

First Out.

Jim,

I know in our plant we have several machines that we do that very thing on. We write the data until we get a fault then stop. We use a list of faults that will interupt the write logic. This leaves you with the data just before the fault. We do the write at each scan because things change faster than each second on our equipment and would not get the correct data. You could do the same thing using a timer and interupting the logic for it when you get a fault.


O Fault1
O Fault2
O Fault3
= StopWrite

an StopWrite
= Writedata


The above might give you a place to start. If not the rest of the guys on the forum will be in on Monday and will have better examples.


Larry