Control Mode:

In the proportional control mode, the last control element is throttled to several positions which are dependent on the process system conditions.  For instance, a proportional controller gives a linear stepless outcome which can position a valve at intermediate positions, as well as "full open" or "full shut."  The controller operates inside a band in which is among the 0% output point and the 100% output point and where the output of the controller is proportional to the input signal.