general info that will apply to any control system regarding noise.
Google search for document "gmc-rm001"
http://www.google.com/url?sa=t&source=web&cd=1&ved=0CBcQFjAA&url=http%3A%2F%2Fsamplecode.rockwellautomation.com%2Fidc%2Fgroups%2Fliterature%2Fdocuments%2Frm%2Fgmc-rm001_-en-p.pdf&rct=j&q=gmc-rm001&ei=CRz5TMuUJ8qJnAeU6JSOCQ&usg=AFQjCNEWdjisRRG3hmiAoJqjtSsXcuCzDw&cad=rja