AutoCAD Electrical is meant for control system design, and will handle schematics as well as panel layout. I've been using it for a couple of years now. It still has a way to go, but I find I can customize the parts databases easily to add components that don't appear in the base package.
I create PLC I/O drawings with a standard field device in each line, then I export to an Excel spreadsheet, make my changes there, and import the corrected version. All the devices update to the correct symbol/name etc.
xnuke
"Do you think you used enough dynamite there, Butch?"
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.