Below are a few top links useful when designing automation systems.
Rockwell Automation Knowledge Base
In depth articles and solutions that the user manual doesn’t always detail.
Siemens online configuration tool for finding product and part number.
Electronic Data Sheets for Allen-Bradley Products.
Flash Update Files, Product Help Files, Control Bar Files, GSD Files, EDS File links
Great solutions for networking your automation system.
Good, unbiased review of new products and industry trends.
Control Engineering
Magazine to keep up with industry trends and technologies in automation.