Programmable logic controller: Difference between revisions

Revision as of 17:54, 25 February 2004

Revision as of 17:56, 25 February 2004

Line 5:

===Examples===

A crapsimple program could maintain the level of water in a tank between two float switches by opening and closing an electric valve. A slightly more complex arrangement could involve a scale under the tank (as an input) and a flow controller (as an output) allowing water to flow at a controlled rate. A typical industrial application might control several tanks in a process such as sewage treatment. Each tank might be watched for a variety of conditions such as being too full or too empty or having the wrong pH.