Micrologix 1200 SAving to EXCEL

[connellrichard 0]

I have a micrologix 1200 saving HIGH/GOOD/LOW information from a sensor to an excel spreadsheet cell. This is overwritten each cycle of the test machine I have built which is cycling once every 2 seconds. I want to save the status of the HIGH=0/GOOD=1/LOW=0 bits and add a time stamp column and save as many sample points as possible (If possible up to 30,000). Can this be done - I have the data coming into Excel but I want to save it to an array and time stamp it so I know the data is unique by doing some tests and making parts fail. Any ideas

[BobLfoot 301]

Yes this can be done. You'll need to use an Excel macro and write some VBA code. Check out the downloads section of mrplc for sample excel sheets reading data.

[Nathan 7]

This is possible with VBA scripting using DDE calls to read from the PLC via the OPC Server (RSLinx). The constantly updating portion of your post is OK. Using Excel as a datalogger is possible, but a really bad idea for many reasons. You can save 30k points. Excel has a builtin row limitation of 65k (2^16). After that point you'd need to programatically write to different files or tabs. If you're required to keep records, this will fulfill that check in the box. Practically speaking, analyzing/data mining a whole bunch of separate files isn't going to happen. This post gets into more of the details. Edited 5 Dec 2007 by Nathan