Robin2:
My practical tests have suggested that it makes no sense to read the temperatures faster than they can change. It works much better with samples at 6 seconds rather than 1 second and I assume that is because there is not sufficient change in the temperature in 1 second even when the heating effect is strong.
...R
I don't reckon that the system will work 'better' when sampling period is increased. If it works for 6 second sampling period, then it should work for 1 second sampling period.
But then again...... it depends on what the PID coefficients are (if you're using PID), since changing sampling period can alter the behaviour of a control system.
And..... depending on what the initial temperature is and what the temperature would be (without heating for a long enough time), one set of PID coefficients might work better than another set.