Electric Connections of the process in open loop (diagram)
The open loop process control system is the most basic kind of control loop. It includes two components: the control instrument and the manipulation instrument. This system creates a variable output, which is determined by the setpoint. As the system does not have sensors, it is unable to automatically correct changes in the process, then, it cannot be considered a measurement instrument (AMATROL, Inc; 2009). A general one is shown on figure 4
For our process (figure 3), the open loop consists of the connections of the PID controller to the flow valve and the pump to the on/off handdle so the tank can be filled as necesary. As no sensor is connected in the circuit, there is not feedback, therefore it is only possible to measure the level in tha tank by observing it and to controll the flow with the handdle.
For our process (figure 3), the open loop consists of the connections of the PID controller to the flow valve and the pump to the on/off handdle so the tank can be filled as necesary. As no sensor is connected in the circuit, there is not feedback, therefore it is only possible to measure the level in tha tank by observing it and to controll the flow with the handdle.