Pressure controllers accept input from pressure sensors, transmitters, gauges, and other devices and subsequently control adjustment to the pressure to maintain or achieve the desired pressure level.
Pump controllers monitor flow and/or level variables, and control a pump accordingly to maintain the desired levels. Pump control can include simply turning a pump on and off, or more advanced controls for pump speed, output pressure, etc.
Temperature controllers accept inputs from temperature sensors or thermometers, and then output a control signal to keep the temperature at the desired level.
Universal process controllers constitute a broad area of control devices that may be employed in the monitoring and control of many different process variables, including temperature, pressure, flow and other values.