Bill Sloman wrote: > This is proportional-derivative control implemented by someone who > hasn't heard of proportional-integral-derivative (PID) control. Google > for an absolute flood of information. > > http://lorien.ncl.ac.uk/ming/pid/PID.pdf > > It is a technique that has been around for a while - the Ziegler-Nichols > tuning technique for PID controllers refers to the paper they published > in 1942. > I don't know much about control engineering, but in the text was also a paragraph about PID. But they said that this would require at least 3 parameters, and would be too complex, and that adapting a PID-controller to the oven would require founded awareness in controling engineering. Stefan