"Control products just keep getting more advanced, yet simpler to use,"was the consensus among editors at Control Engineering when it was time for them to choose the best control products of 1997. For the 11th consecutive year, the editors chose the 50 best products based on three criteria: technological advancement, impact on the market, and service to the industry.
Processes with large deadtimes present a special challenge for a controller—any controller. The controller must wait until the deadtime has passed before it gets any feedback from the process.The best thing to do for controlling this type of process is to try to reduce the dead time. Simply moving a probe closer to the valve may do it.
PID loops control a majority of the automated processes in industrial facilities. The proportional-integral-derivative (PID) algorithm is both simple and reliable, and has been applied to hundreds of thousands of control loops over the last 50 years.However, not all industrial processes can be controlled with PID loops.