How Do I Calculate Dead-Time?

Adults can learn a thing or two from children. That’s especially true when it comes to matters of time. Whereas adults view it as fashionable to show up to a social event 15 or more minutes late, children can’t wait to go and be a part of the action. When at a theme park adults typically their time strolling from place to place while children know that each minute of delay can cost hours longer in line. Simply put: When it comes to time every second matters. That viewpoint seems highly relevant to process control, control loop tuning, and calculating Dead-Time. Dead-Time is generally the model parameter that’s easiest to calculate when tuning a PID controller.

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What is the Process Time Constant? How Do I Calculate the Time Constant of A Process?

Party hosts often cringe when guests arrive early or late. Seemingly subtle shifts in timing can throw off planned details that are of importance to the host and utterly lost on guests. So too the timing of a PID control loop’s response is important. Premature or delayed responses negatively impact the controller’s performance. Previously the calculation of Process Gain – the “how far” variable – was covered. The Process Time Constant is equally important to process modeling and PID controller tuning. As with most things, timing is everything.

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