S7-300 PN/DP

Dear All,

i am facing an issue with S7-300 PN/DP CPU its work memory is 99% full and i am having strange issues with that system on my SCADA some of mu routines won't start for instance..

i have one FB to start one area automatically by pressing the button on SCADA sometimes the stop button will start to blink to show that the area is being stopped and i am not able to press start even if i press start it will start and again go back to stop.

then what i do is delete every thing from the plc Online and download again the complete program then it becomes O.K for sometime. i check the bits linked to the buttons online they seem to be O.K.

just need to know whether there really is a problem or just because of this work memory this is happening should i replace my CPU with a one with larger work memory...

please help...

Hi, 

I guess memory full will not be responsible for stopping of the plant so please check the logic too and 

please have a look into it..http://www.google.co.in/search?q=compress+and+download+s7+300+memory+full&site=webhp&ei=zjArVd-RCI2MuASsqoDQBw&start=300&sa=N