sTEm–at-Work Puzzle #52: Process Pressure Disturbance

A technician works in a company that manufactures micro scale laser devices in a vacuum chamber.  The tech had to replace the vacuum pump that controls the pressure in this chamber.  To bring this pump back on line, the tech turns the pump on and lets the chamber reach its steady state low pressure value (the set point pressure). The tech now must adjust the programmable controller driven pump control panel settings to values that automatically try to return the pressure in the chamber back to this pressure set point value after the tech changed the pressure in the chamber (a disturbance) by adding a small amount of nitrogen gas into the chamber. The tech tested three different sets of control panel settings with the three corresponding pressure versus time graphs shown below.  

The technician selected the setting that provided the graphic response shown as graph number 3.    YES or NO

Submit your answers below the blog, or on