rslogix 500 trend function usage

[kjmc]

hi, how long will the trend accumulate data? Forever, or will it start scrolling over itself eventually? I set it to refresh every automatically at 250ms. i forgot the terminology but there was a Pen display overflow or something, the default was 200, I set it to 32767, the max; sorry, i dont have the program in front of me now for the exact term. I would like it to be able to collect for several days. I do know that someone would have to save it before closing the program using the create snapshot. If not then I need to be able to come up with a duration so that if the problem does happen then I can have people go and save the snapshot shortly thereafter. I couldnt find much detailed guidance on the topic of using the trend functions. thanks for your help.