jrs

Thanks for your reply. First of all, let me add a bit more. I have three machines that are all the same, same applications, and all three are responding the same. One will run fine for a week or so before it acts up, one couple of days, while one acts up every couple of hours. Today one was crashing every half hour or so. On the screen it indicates the sequence of comm error reading/writing analog/dogital data. In the alarm file it has the same indication plus the number of fatal PLC errors. The PLC, fault indicator isn't on, and the S:6 register is 0. Sometimes if you just close the VB application the machine starts right back up, other times you have to uninstall the application, remove the directories for the root, and reinstall it to get back up and running. Never saw anything like it before.

Running a simple application using a Versaview 1200P and a SLC 505. Problem is that keep getting a number of comm error unable to read digital data, comm error unable to write digital data, comm error unable to read analog data, comm error unable to write digital data. When these errors occur (they all come up in sequence) they are followed by a major error code though the processor doesn't indicate any fault. Fault codes 96H, 95H, 94H, 93H, 75H, 73H. Problem is driving me up a wall, can anyone shed some light on this? Thanks.