A sample flow for demonstrating the PID loop controller node-red-contrib-pid using a process simulation consisting of a 3 second transport delay followed by 10 second and 30 second lags and an offset.
A guide to tuning a process controlled by a PID controller, which uses this flow as an example to demonstrate the prinicples can be found at https://blog.clanlaw.org.uk/pid-loop-tuning.html
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