Instrumentation and control (I&C)

Instrumentation and control (I&C) covers all the components that allow an installation to “know” what is happening inside it and respond accordingly. The simplest way to picture it is as the installation’s senses and muscles.

The measuring part (the senses) consists of sensors and transmitters that measure, among other things, temperature, pressure, product level in a tank and flow, as well as quality parameters such as pH, conductivity and density.

The actuating part (the muscles) consists of devices that take action based on those measurements: on/off valves that open or close the flow, control valves that adjust it smoothly, and drives for pumps and agitators.

Between them is the controller (the brain), which receives the measurements and makes decisions. The field that deals with I&C is simply called industrial automation.

Example: In a pet food plant, jelly for wet food is prepared in a tank. A level sensor detects that the tank is 95% full, so the controller closes the inlet valve and switches off the pump before the jelly overflows. At the same time, a temperature sensor makes sure the jelly does not cool down and start to set in the tank. When the temperature drops, the controller opens the steam valve in the tank jacket and heats the jelly back to the setpoint.