When I lower the set-point, PID goes to min

[lukepighetti]

Temp was 275f, set point was 275f. P is 3 and I is 0.01

Changed set point to 250f. It immediately dropped to the minimum. I expected it to smoothly transition.

Is this a tuning problem or a bug?

[soloam]

What version of the PID are you running? Is it the latest?

[soloam]

Normally that bump is because you might have a very high "p". Give me your config, aren't you using the "d"?

[Pukinn]

I have the same issue. But it's not because of a high Kp. It seems the controller resets after changing the set_point. The attributes p, i, d are going to 0. If a high Kp were the reason, I think p should go to a negative value.
Also it goes to min value, if I increase the set_point (invert == false).

I use the latest version 1.1.5

[soloam]

Yes the pid is resetting when the set point is changed! Probably this could be avoided, but I don't know if in some cases it wouldn't be desirable!

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On Thu, Dec 15, 2022, 14:35 Pukinn ***@***.***> wrote: I have the same issue. But it's not because of a high Kp. It seems the controller resets after changing the set_point. The attributes p, i, d are going to 0. If a high Kp were the reason, I think p should go to a negative value. Also it goes to min value, if I increase the set_point (invert == false). I use the latest version 1.1.5 — Reply to this email directly, view it on GitHub <#31 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AC3FPI53W6SHKC4JECYBXPLWNMUB7ANCNFSM6AAAAAARIJJOP4> . You are receiving this because you commented.Message ID: ***@***.***>

[Pukinn]

In which scenario this could be desirable? After a change of the set point I expect a correction because of the derivative part in the next cycle.
But I increase the set_point and the correction goes down to 0 until the next update of the source.

I think the controller should only reset if the reset is manually triggered.

[soloam]

I agree with that! The reason to do this is to avoid sudden spikes up in the pid, but this is making the spike down! I'll fix it!